This article presents an overview of damage to highway bridges following the Hanshin-Awaji earthquake. Ian Buckle was a member of the U.S.-Japan Natural Resources (UJNR) reconnaissance team organized by the National Institute of Standards and Technology and partially supported by NCEER and the Federal Highway Administration. This team visited the Hanshin region from February 11-17. Dr. Buckle also visited the region from March 11-17 at the invitation of the Public Works Research Institute of the Ministry of Construction. Questions and comments should be directed to Dr. Buckle at (716) 645-3391. Two NCEER reconnaissance reports are currently being compiled and will be available later this year; one concerns the performance of lifelines and the other the performance of bridges.
The Hanshin region of Japan comprises parts of the Hyogo, Kyoto and Osaka Prefectures to the north and east of Osaka Bay. The population of 12.5 million people living and working in the region is served by a complex network of modern freeways and highways built in the last thirty years (since the early 1960's). These major transportation routes generally run parallel to the shoreline of Osaka Bay with major links to the east to Nara, to the northeast to Kyoto, and to the west to Himeji. As the mountains behind Kobe approach the Bay shoreline, the east-west routes are forced into a narrow corridor which is barely 3 km wide in some parts and which must be shared with three major rail lines. Soil conditions vary throughout the region but most of the highway structures are founded on sand-gravel terraces (alluvial deposits) which overlie gravel-sand- mud deposits at depths of less than 10 m. Liquefiable soils are present along the shoreline and in most ports and channels. As a consequence, piled foundations are used extensively and caisson foundations are common for those large bridges that are in port areas or cross shipping channels.
Responsibility for the design, construction and maintenance of these highway routes is divided between the Ministry of Construction and two Public Expressway Corporations. Highways under the jurisdiction of the Ministry of Construction are free for public use whereas those owned by an Expressway Corporation are toll roads and road user fees are collected. These latter Corporations are independent authorities but are nevertheless subject to government control and regulation.
The Ministry of Construction (MOC), through the Naniwa National Highway Work Office, has oversight for the National Highways (NH) in the region. These include Routes R-2 and R-43 which join Osaka with Kobe, as well as several other trunk roads such as Routes R-428 (Kobe to Chugoku Expressway), and R-171 (Nishinomiya to Kyoto and Route R-1). These arterial highways are generally surface routes but with some notable elevated sections. These include the Route 2 Hamate Bypass on the Kobe waterfront, the Port Island Connector and the 6.6 km-long, Airport Access Highway to the new Kansai International Airport in Osaka Bay.
One of the two Expressway Corporations noted above is the Japan Highway Public Corporation (JHPC) which is responsible for at least three major freeways (expressways) in the region. These are the Meishin Expressway (the first such expressway in Japan) and the Chugoku and Kinki Expressways. The Meishin runs in a northeasterly direction from Osaka Bay (at Nishinomiya) to Kyoto. Both the Chugoku and Kinki Expressways start from Suita City, just to the north of Osaka City, and run west and south respectively.
The second Expressway Corporation noted earlier, is the Hanshin Expressway Public Corporation (HEPC). It is one of the largest such Corporations in Japan and is, today, responsible for approximately 200 km of freeway-standard highway throughout the Hanshin region. Opened in 1964 with an initial length of 2.3 km in Osaka, it has grown in both size and capacity during the intervening 30 years. Almost a million vehicles per day used the system in 1994, with the highest traffic counts (131,500 per day) being recorded on the four lane, loop expressway in the center of Osaka City. For the fiscal year 1993, the average income from tolls was Ñ340 million per day (approximately $3.4 million). More than 90% of the system is elevated, supported on about 8,500 spans. Of these, 83% are steel and 17% are concrete spans. Most substructures are single column concrete bents but single and multicolumn steel bents are also used to a significant degree.
The HEPC has an active maintenance program and currently spends about Ñ30 billion per year (approximately $300 million) in this area. It also has an ongoing seismic retrofit program and has for many years used earthquake couplers to restrain the free ends of simply supported girders. The Corporation has recently begun to investigate the use of steel jackets for improving the performance of concrete columns and has installed some trial jackets on single column bents at the west end of Route 3.
Seismic design criteria for new structures meet or exceed those required by the Japan Road Association (Design Specifications, etc., 1990; Iwasaki et al., 1990). Furthermore, the HEPC has been proactive in the use of energy dissipators in bridges and, as early as 1981, completed the Yoshino-Tamagawa Viaduct on Route 3 in Osaka, using viscous shearing dampers. More recently, the HEPC has constructed two menshin (base isolated) bridges on Route 4 (the Wangan Route near the new Kansai Airport). These are the 4-span, Matsunohama bridge (1994) and the 6-span, Izumisano bridge (1994); both use lead-rubber (LRB) isolators. The Matsunohama bridge is instrumented for strong ground shaking with 9 accelerometers and a 23-channel data acquisition system.
Table 1: Location of Bridges with Major Damage _________________________________________________________________ Route No./ Owner/Agency No. of Bridges with Expressway Major Damage _________________________________________________________________ 2 (NH) Ministry of Construction 3 3 (Hanshin) Hanshin Expressway Public Corp. 11 5 (Hanshin) Hanshin Expressway Public Corp 4 43 (NH) Ministry of Construction 1 171 (NH) Ministry of Construction 2 Meishin Japan Highway Public Corp. 4 Chugoku Japan Highway Public Corp. 2 TOTAL 27
Notes: (NH) = National Highway _________________________________________________________________
A large number of bridges were damaged in this earthquake and one estimate of the affected number is of the order of 60% of the total inventory. An exact number is difficult to count because of the use of long elevated sections that are tens of kilometers in length and the line where one bridge (or segment) ends and another begins is difficult to determine. Furthermore, several structures at the same interchange may be identified, in some damage reports, as one "bridge". A more precise measure of the extent of the damage is the number of collapsed and damaged spans but such information is not available at this time. Accepting these limitations, the number of highway "bridges" that sustained major damage (including collapsed spans) is on the order of 27. Many more suffered moderate-to-minor damage such as pounding, spalling of cover concrete and settlement of approach fills.
The 27 structures that were severely damaged by this earthquake are listed by route number in Table 1 and identified by name in Table 2.
It is seen in Table 1 that the HEPC suffered the largest loss, most probably because it has the largest inventory of elevated structures of any agency in the Hanshin region. One estimate for the direct cost of this damage is Ñ500 billion (approximately $5 billion). Despite the ex-tent of this damage, Route 5 is expected to be reopened by Golden Week (the first week in May), except for access to Rokko Island. Route 3 will be open by the fall of 1995. Of the two routes, Route 3 is the oldest by about 30 years and this probably accounts for the higher dam-age rate compared to that on the newer Route 5.
Approximately 700 columns on Route 3 will be temporarily repaired and about 50 spans will be replaced before it is opened to traffic in the fall. Eventually, about 200 of these 700 columns will be replaced and the remainder will be strengthened to meet new seismic design criteria. By contrast, Route 5 did considerably better despite poorer soils and difficult foundation conditions. The most likely reason is the improvement in the seismic codes during the intervening 30 years and the fact that a major revision was completed to the design specification in 1990 (Design Specifications, etc., 1990; Iwasaki et al., 1990). This revision was in effect during the design of some, but not all, of the structures on this route.
Typical damage sustained by these structures includes shear and flexural failures in nonductile concrete columns, flexural and buckling failures in steel columns, steel bearing failures under lateral load, and foundation failures due to liquefaction (see figures 1, 3 and 4). In addition, there was pounding between spans, failure of several earthquake couplers, and settlement of many approach fills. Not so typical was the failure of a skewed bridge on pin-ended columns and the fracture of a set of holding down bolts in a wind shoe of a cable-stayed bridge which then led to the failure of the seismic energy dissipators and other hardware at this location.
Table 2: List of Highway Bridges with Major Damage _________________________________________________________________ HIGHWAY BRIDGE NAME BRIDGE TYPE (ROUTE NO.) _________________________________________________________________ Hanshin (3) Takashio District Overpass steel girders/concrete columns Futaba District Overpass steel box girders/steel columns Tateishi District Overpass steel box girders/steel columns Hirata-Fukae Overpass(1,2) concrete girders/concrete columns Fukae District Overpass steel box girders/concrete columns Mikage District Overpass steel box girders/concrete columns Uozaki Ramps(1) steel girders/concrete columns Kaigan-dori-Benten Overpass concrete and steel girders/concrete columns Hyogo-Nagata District Overpass(1,3) steel girders/steel and concrete columns Minatogawa Ramps(1) steel girders/concrete columns Sanyo Rail Line Overpass(1) steel box girders/concrete columns Hanshin (5) Nishinomiya-ko Bridge(1) Nielsen-Lohse tied arch/steel columns Shukugawa Bridge(1) steel box girders/concrete multicolumn bent Higashi-Kobe Bridge(1) cable stayed deck/steel columns Rokko Island Bridge(1) Lohse tied arch/steel columns Meishin Moribe Viaduct(1) concrete box Girders/concrete pier walls Mukogawa Bridge(1) steel girders/concrete columns Kawaraginishi Bridge(1) concrete box girders/pin-ended concrete multi- column bent Nishinomiya Interchange Chugoku Takarazuka Viaduct(1) concrete box girder/concrete multi-column bent Toyonaka Overpass National Highway Hamate Bypass(1) steel box ( NH 2) girders/steel columns Kobe-Port Island Ohashi(1) steel box girders/concrete dual level 2-column bent Shioya Overpass National Highway Iwaya Overpass concrete (NH 43) girders/concrete columns National Highway Mondo Overpass concrete (NH 171) girders/concrete columns Ikeda Overpass _________________________________________________________________ Notes: 1. Sites visited by UJNR Reconnaissance Team Feb. 11-17, 1995 2. Includes Higashi-Nada Viaduct 3. Includes Meiji District _________________________________________________________________
To bridge engineers and owners in the central and eastern United States, this particular earthquake is perhaps of greater significance than recent earthquakes in California (e.g., Loma Prieta, 1989 and Northridge, 1994). One reason for this opinion is that the predominant type of bridge in Japan is the steel girder superstructure (simple and/or continuous spans) supported by bearings on concrete columns and foundations. This class of bridge is also found throughout the central and eastern U.S., whereas bridges in California tend to be concrete box girders with monolithic bents and abutments, especially in shorter bridges.
A second reason is that an earthquake of this size was considered to be a rare event for this part of Japan. Although bridges in this region are designed for seismic loads, the design coefficients are considerably lower than those recorded during this earthquake. The possibility of an earthquake larger than the design earthquake was considered to be so unlikely that only nominal attention had been given to the problem and then only for structures designed since 1990. This difference between the maximum credible earthquake and the design earthquake is clearly very large for this region of Japan - a situation that is also considered to exist in the U.S., but to a greater degree in the eastern and central states than in the west.
It follows that the eastern and central U.S. may have more to learn from Japan than from California. Some of these lessons are as follows:
Damage to highway bridges was both widespread and catastrophic. Most of this distress was confined to older structures built more than 30 years ago and before the introduction of modern seismic codes. The poor performance of these older bridges and elevated expressways confirms previous lessons learned in California and elsewhere about the pressing need to retrofit the existing inventory of deficient bridges.
However, some new bridges also suffered serious damage which suggests a need to re-evaluate the design loads and procedures for these structures. There is strong evidence to indicate that the peak ground accelerations were considerably higher than the seismic coefficients used for bridge design in the region. The occurrence of this damaging but "rare" earthquake raises doubt, once again, about the correct level of the design load and reinforces the need for dual-level performance criteria. These criteria should clearly state the expected performance under both large and small, rare and frequent, earthquakes and identify design strategies and procedures that will satisfy these criteria.
Both of these observations are also applicable to the United States and in particular to those States where moderate-to-large earthquakes are considered to be possible, but rare, events.
The closure of three major expressways in the Hanshin region has had a major societal and economic impact on the region. It is expected that the indirect costs due to loss of use will exceed the direct costs of repair and replacement by the time these routes are reopened for traffic. The simultaneous closure of other transportation routes in the region, principally the rail lines, further aggravated the situation and paralyzed the region as emergency access and relief teams were forced to use surface streets. The interdependency of these lifelines, especially when collocated in narrow corridors, deserves further study.
"Design Specifications of Road Bridges; Part V: Seismic Design," (1990), Japan
Iwasaki,T., Kawashima, K. and Hasegawa, K., (1990), "New Seismic Design
Specifications of Highway Bridges in Japan," Proc. 22nd Joint Meeting US-Japan
Panel on Wind and Seismic Effects, UJNR, Gaithersburg, MD.
This article presents an overview of geotechnical observations following the Hanshin-Awaji earthquake. Carl Costantino was part of a federal reconnaissance team organized by the Nuclear Regulatory Commission (NRC) and the Department of Energy (DOE). The team was headed by Dr. Nilesh Chokshi of the NRC, and was supported in Japan by the Nuclear Power Engineering Corporation (NUPEC). The team consisted of nine members, two each from NRC, DOE, Lawrence Livermore National Laboratory (LLNL), Brookhaven National Laboratory (BNL) (including the author), and one from NUPEC. The team was in the Kobe area from February 12-19. Their primary goal was to gather information needed to help assess the methods and procedures that are currently used to evaluate critical facilities investigated by both NRC and DOE. Questions and comments should be directed to Dr. Carl Costantino at (212) 650-8003.
Upon arrival in Kobe, the Nuclear Regulatory Commission (NRC)/Department of Energy (DOE) reconnaissance team met with personnel from the local power company, Kansai Electric Power Company, and with faculty members from the University of Kyoto. They were provided with a significant amount of detail on the damage that had occurred, the state of cleanup activities, and other data that was available at the time. The team then conducted a number of walking tours of the damaged region between Kobe City and Osaka (Akashi, Nagata, Hyogo, Nada, Nishinomiya, Amagasaki and Itami), the epicentral region on Awaji Island and the artificial islands (Port and Rokko) in the harbor. These locations are shown in figure 5. The team split into two subgroups, one focusing on geophysical and geotechnical issues and the other focusing on structural and equipment issues. A number of large commercial facilities with characteristics similar to critical facilities of interest were visited by the second subgroup and damage states were evaluated.
Some ground motion and foundation information was provided to the team, as well as to other groups inspecting the damage, which will be useful in evaluating geotechnical and geophysical issues. For example, a number of the active faults in the Kobe area were previously mapped by the Research Group for Active Faults and are shown in figure 6 together with their identification numbers. The rupture in the epicentral area occurred along Fault Number 1 on the northern tip of Awaji Island and is known as the Nojima fault. The fault is approximately 7 km long. Surface expression of the rupture occurred along the entire fault line and indicates a horizontal slip (right-lateral motion) of as much as 48 inches (1.2 m). Vertical slip was also noted and was as much as 24 inches (0.6 m) and varied along the fault from NW-up to NW-down. The slip extended into the harbor area as indicated by the movement of the towers of the new suspension bridge being constructed across the Akashi Straits. At the time of the reconnaissance trip, surface fault expression was also noted in the Itami area northeast of Kobe and movement was confirmed along faults 63, 64 and 65. Based on these surface expressions, the total fault length is therefore estimated to be of the order of 50 to 60 kms.
A number of records are available from the event from which peak ground accelerations (PGA's) were determined. From information provided by a number of sources1, an approximate composite location map was generated and is shown in figure 7. The map indicates the larger of the two horizontal PGA's in gals (cm/s2) from the recordings. Several of these are considered questionable since the recordings were clipped. As can be noted, the largest acceleration is 833 gals (0.85g) and occurred at a shallow soil site in the Kobe City area. The 5% damped response spectrum associated with this record indicated a peak spectral acceleration in the 1 to 3 hz range exceeding 2000 gals (or 2g) and a peak spectral velocity at 1 hz exceeding 200 cm/s (80 in/sec). This spectral velocity is over twice that from the El Centro record. These motions are obviously larger than typical ground motions used for structural design, particularly in the low frequency regime and may explain the extent of damage noted. Using an initial estimate of distance from the recording stations to the fault provided by Professor Toki of the University of Kyoto, an attenuation plot was made and compared with the Boore, Joyner, Fumal 1993 attenuation model for soft soil (see figure 8).
One of the efforts being undertaken is to more closely quantify site conditions to better determine a median attenuation model and uncertainty for this event. The ratio of vertical to horizontal PGA's is of interest in structural evaluations and slope stability calculations. The average ratio is 0.87, higher than the 2/3 value typically assumed. In addition, in the region close to the fault at Kobe City, the ratios are generally low while in the area across the bay in the Osaka region, a greater portion of the readings exceed unity. Considering that the cross-section between Kobe and Osaka indicates a deep dish of bedrock filled with relatively soft soil, two dimensional valley effects may explain this distribution.
Much of the geotechnical information noted by the team has been noted by other groups and published previously. For example, the fault area along Awaji Island showed clear indications of the rupture (figure 9) along the entire Nojima fault segment and is easily traceable. The artificial islands constructed in the harbor (such as Port Island) were constructed by fill methods with little emphasis placed on compaction to achieve high relative density. Settlements on the islands close to the fault (Port and Rokko Islands) were of the order of three to five feet (.9 to 1.5 m), but amazingly, were essentially uniform across the islands. Significant damage occurred to dock facilities as well as connections to pile supported structures. The settlement effects are clearly manifested by displacements adjacent to pile caps for highways and bridges. The port area of Kobe City similarly sustained significant damage to surface slabs of dock facilities (figure 10). In general, pile supported facilities faired well during the event although some damage was noted. For example, the caisson supported sea wall on Port Island (figure 11) showed lateral movement at some locations and extensive collapse of pavements immediately in front of the wall.
A number of slope failures occurred throughout the area, the most serious of which was the slide at Nigawa at which a number of people were killed (figure 12). Much of the material downhill from this slide indicates clean sand fill rather than natural materials. The remaining structures at the top of the slope are founded on small concrete piles into the natural soils. Small slope failures were noted on Awaji Island, although the magnitude of these failures is smaller than the failures in the Kobe City vicinity. In general, the failures, both structural and slope, on Awaji Island were viewed to be less catastrophic than those noted in the Kobe and Nishinomiya areas, although significant damage did occur to the older style homes at Awaji. However, no damage was noted to have occurred to any relatively modern building as was noted on the mainland. As mentioned above, the ground motions measured in the Kobe City area indicated high acceleration levels associated with the low frequency components of the motions. Such behavior can be induced in these areas by the softer soils overlying the bedrock. This overburden configuration is not as apparent along Awaji Island.
(1) Sources include Research Institute, University of Tokyo; Civil Engineering Department, University of Kyoto; Kansai Electric Power Co.; and the Committee for Monitoring Strong Ground Motion in Kansai Area.
This article describes research conducted to date on the development of a systems analysis methodology to evaluate the seismic performance of lifeline systems. Comments and questions should be directed to Professor M. Shinozuka at (609) 258-6757 or Professor Howard Hwang at (901) 678-4830.
This study was performed to develop a systems analysis methodology to evaluate the seismic performance of Memphis Light, Gas and Water's (MLGW) lifeline systems, the model of which could then be transported to other lifeline systems. A multi-disciplinary group of NCEER's lifeline project researchers used empirical, experimental, analytical and computational methods to develop the methodology. A geographical information system database (ARC/INFO) was used extensively for MLGW's lifeline systems hardware and for geotechnical and soil information.
The overall seismic performance of MLGW's lifeline systems was examined in terms of: seismic hazard and ground motion characteristics of the area; geotechnical features, with a special emphasis on liquefaction and resulting lateral spread; the effect of ground motion and geotechnical features on the seismic performance of mechanical and structural components including pipe-lines, storage tanks, pumping stations, treatment facilities, etc., measured in terms of fragility quantities; reliability and interactive nature of system functionality under severe seismic conditions with the aid of Monte Carlo techniques using component fragility information; and the socioeconomic impact arising from system failure.
This article describes the serviceability analysis performed on the Memphis water delivery system, the interaction between MLGW lifeline systems, and repair and restoration strategies.
The water delivery system of Memphis, Tennessee is shown in figure 13. It consists of a low-pressure system which is found in the geographically central part of the system and several high-pressure systems in the outskirts of the city. The system comprises approximately 1,300 links and 960 nodes. The total length of the buried pipes is about 850 miles (1370 km) whose diameters range from 6.2 inches (16 cm) to 48 inches (122 cm).
There are eight pumping stations in the low-pressure system and one small pumping station in a high-pressure system as of 1990. In addition to the pumping stations, six elevated tanks are used in the high-pressure systems, although several other tanks are reserved for firefighting purposes.
Nine booster pumps are on the pipes through which the low- and high-pressure systems are connected. These booster pumps supply the water to the high-pressure systems. Since only one small pumping station exists in the high-pressure system, most water is supplied by the booster pumps and/or the elevated tanks, depending on the demand condition in the high-pressure system. Two other booster pumps are working in the low-pressure system to support an overloaded pumping station.
The maximum hourly flow rate, maximum volume and the average volume pumped per day in the entire system by month have been well documented by MLGW. The system leakage, which is approximately 15% of the total volume, is included in these numbers. The demand condition used in the analysis for each node corresponds to the maximum demand condition, i.e., the flow rate of the peak hour in June is equal to 296.4 million gallons per day.
A state-of-the-art hydraulic network analysis method was used. The water head and pressure were measured on March 12, 1990 at several check points in the network for system operation purposes. To verify the flow analysis method, the calculated water head values were compared with those measured at a number of nodes where good agreements were demonstrated.
Geographic information systems (GIS) are computer software tools that assist in the acquisition, manipulation and retrieval of spatial data. In this study, a GIS package called ARC/INFO (ESRI, 1989) was used. A computer code was developed to perform these functions by using the macro language and menu interface of ARC/INFO, thus enabling the user to operate the code easily and effectively (Sato et al., 1991).
Data Preparation: Locational, topological and other features of links and nodes were digitized and stored in a computer as a digital map. Each feature was related to the attributes in the database. Both features and attributes can be accessed interactively using the editing capability of the code, so that an arbitrary network can be created on the computer.
Ground Motion Estimation: In this study, the peak ground acceleration (PGA) was used as a primary parameter to represent the intensity of ground motion. Based on an earthquake scenario, PGA values for specific sites in the case study area were computed in the manner described at the Center for Earthquake Research and Information (CERI), University of Memphis (Hwang et al., 1990). These data were interpolated using the weighted average method (Burrough, 1986) and converted into a digital map which represents the distribution of the PGA. Similarly, a digital map for liquefaction potential was developed. Flow Analysis and Damage Simulation: The digital map of the water delivery network developed above was then overlaid with the distribution map of the PGA employing the spatial operation capability of ARC/INFO, so that the PGA value could be assigned to each pipe segment in an automated manner. A flow analysis of the intact network system was then carried out and the results, including the water head and flow output, were stored in the database.
The next step was to simulate pipe failure using the Monte Carlo method to generate a state of seismic damage sustained by the network. In the present analysis, the pipe failure rate r (breaks per km) was assumed to be a function of PGA, local soil conditions and pipe material. For cast iron pipes, a function proposed by Katayama, et al. (1975) was used, while for ductile iron pipes, a function by Craig, (1991) was used.
Assuming a Poisson distribution in the occurrence of pipe breaks, the probability, Px, that the number of breaks in pipe i with length Li is exactly equal to x is given by Px = (rLi)x e-rLi /x!. Hence, the probabilities that pipe i has no break (no damage by definition), one or two breaks (minor damage), three, four or five breaks (moderate damage) or more than or equal to six breaks (major damage) can be computed. By performing a similar simulation for all pipes in the network, the state of physical damage for the network was simulated.
In the computer code used (Tanaka et al., 1994), water leakage from a damaged pipe was treated by accounting for these states of pipe damage. Also, in the present code, the possibility of pumping station failure was examined by overlaying the map to indicate the locations of pumping stations (with the fragility previously established) over the PGA map.
The flow analysis was repeatedly performed in a Monte Carlo method on each simulated damage state of the network in order to develop statistics on water head and flow output at each demand node. In this study, water head was considered an important parameter in estimating the post-earthquake firefighting capability of the system.
Map Display: One of the important features of the GIS is the effective visualization of analytical results in terms of various forms of mapping on a graphic terminal, which allows the user to examine the spatial characteristics of such results. Most of the figures presented in this article were created using this module.
Development of Computer Code LIFELINE-W: All the functions mentioned above that are required to carry out a seismic risk analysis of water delivery systems were combined into a computer code, LIFELINE-W, and user's manual (Tanaka et al., 1994). The code can be used for the analysis of other water delivery systems with appropriate modifications.
Employing the computer code LIFELINE-W, a case study was performed on the water delivery network serving Shelby County, Tennessee, including the City of Memphis, subjected to the scenario earthquake mentioned above.
Intact Condition: A flow analysis was carried out on the existing network to evaluate flow parameters under intact conditions. It was observed that water heads tend to be smaller in the suburban area than in the urban area, although the output flow rate can meet the demand at most nodes of the system.
Damaged Condition: The damaged state was simulated based on PGA values 25 times on the existing network. Figure 14 shows the average water head obtained from these simulations. The water head significantly declines in the suburban area of the county.
Furthermore, the results of these simulations were overlaid with census tracts to estimate the societal impact of seismic damage to the network. Figure 15 shows the ratio of the output flow under damaged conditions to the output flow under intact conditions in each census tract.
Preparedness, Improvement and Socioeconomic Impact Estimation: This type of information (Shinozuka et al., 1992) permits county and city officials to estimate the shortage of potable water for each census tract immediately after the scenario or similar earthquakes, and possibly more importantly, the degradation of post-earthquake firefighting capability of the system. Depending on the information thus obtained, officials can make a preparedness plan for hauling water for human consumption from neighboring undamaged areas and also start working on improving facilities to ensure that firefighting capabilities be kept above an acceptable level under the scenario earthquake. Other plausible scenario earthquakes must be considered for future earthquake preparedness.
Lifeline system interactions have been suggested to occur and indeed have often been observed under earthquake conditions, particularly under severe events. An analysis of interactions that might occur between water delivery and electric power transmission systems subjected to the scenario earthquake have been performed as part of this study. In carrying out this analysis, however, some of the basic data to describe physical characteristics of the water delivery and electric power transmission systems of MLGW were not available and hence were simulated. In view of this, the result of this analysis, although the first of its kind in quantitative details, must be interpreted accordingly.
Conditions for System Failure: MLGW's electric power transmission network is depicted in figure 16. It transmits electric power provided by Tennessee Valley Authority (TVA) through gate stations to 45 substations in the network consisting of 500kv, 161kv, 115kv and 23kv transmission lines and gates, 23kv and 12kv substations. The 500kv line and gate stations are operated by TVA, while the other transmission lines and substations are operated by MLGW. Each substation is associated with a service area, and usually one service area is served by only one substation (except for two occasions).
In analyzing the functional reliability of each substation, the following modes of failure were taken into consideration; (1) loss of connectivity, (2) failure of substations and (3) power imbalance. Each of these failure modes was addressed in the analysis from the viewpoint of the ensuing reliability analysis of the MLGW's electric power transmission system. Specifically, the most current information on the fragility curves was used for the substation.
Monte Carlo Simulation: A map of the electric transmission network was overlaid with the map of PGA identifying the PGA value associated with each substation. With the aid of the fragility curves developed earlier, the analysis determined the probability of each substation to malfunction under the PGA identified. Monte Carlo simulation was then carried out to generate a large number of states of damage for the transmission system. Each damage state represents one of 2M damage states in which M( specific substations malfunction and the remaining M - M( substations function (M( = 0, 1,...M).
For each damage state, it can be determined whether or not a substation malfunctions due to loss of connectivity. The loss of connectivity occurs when the substation of interest survives the corresponding PGA, but is isolated from all the gate stations because of the malfunction of at least one of the substations on each and every possible path between this substation and any of the gate stations. Hence, the loss of connectivity with respect to a particular substation can be confirmed on each damage state by actually verifying the loss of connectivity with respect to all the paths that would otherwise establish the desired connectivity. This is an easy task, particularly when the network is as simple as considered in this study. It can also easily be determined whether or not a substation malfunctions due to the corresponding PGA. In fact, each simulated state of damage explicitly provides this information.
Finally, the malfunction of a substation due to power imbalance was confirmed by carrying out the flow analysis with respect to the network in each damage state. A special computer code was used for this purpose. Each substation was examined with respect to its possible malfunction under these three modes of failure for each simulated damage state. In the present study, a sample size of 100 was considered for the Monte Carlo analysis. The probability PEm of malfunction of a particular substation m is then estimated as Nm/N=Nm/100, where Nm is the number of simulated damage states in which the substation m malfunctions in at least one of the three modes. On the basis of the flow analysis performed on the network in 100 simulated damage states, the ratio of the average electric power output (in MW) of the damaged network to that associated with the intact network was computed and is plotted in figure 17. The ratio is a convenient measure to show the degradation of the system performance due to an earthquake. The average was taken over the entire sample of 100.
The effect of the performance degradation of the electric power transmission system on the water delivery system serving the same regional community was analyzed using MLGW as an example. Figure 18 shows a map of the electric power service areas together with the locations of the pumping stations and booster pumps of the water delivery system. For the numerical analysis, it was assumed that the pumping stations and booster pumps in a service area ceased to operate due to the lack of electric power if all the substations serving that service area malfunctioned. In the earlier study performed by Hwang et al., (1992), the fragility curve of a pumping station in the MLGW's water delivery system was estimated. Hence, the probability of a pumping station to malfunction under the scenario earthquake could also be estimated. If, therefore, this pumping station is located in the service area served by the substation, then the probability of the pumping station malfunctioning can be written as:
Pj = 1 - (1 - Pwj) (1 - PEm)
Or approximately = Pwj + PEm
where the approximation is valid when both Pwj and PEm are small compared with unity. Appropriate modifications can be made to estimate the probability of malfunction of a pumping station located in the service area served by more than one substation. The probability of a booster pump to malfunction is equal to the probability PEm if the pump is located in the service area served by substation since, in the earlier analysis performed by Shinozuka et al., (1992), the pumping stations were assumed not to be seismically vulnerable. This same analysis was repeated with the added probability of malfunction for pumping stations and booster pumps due to the malfunction of electric power substations. Figure 19 shows the average water head and output flow rate at each demand node of the damaged water delivery network and their ratios to the corresponding values of the undamaged network. Figure 20 indicates the degrading effect of interaction when the impact of malfunction of electric power substations was incorporated into the analysis.
The post-earthquake restoration of a water delivery system is a critical issue. In an earlier approach for optimum temporary restoration of a seismically damaged water network (Shinozuka et al., 1993), a short-route network was first established by determining the shortest route from each demand node to the nearest supply node. The links not included in the short-route network were excluded from temporary repair. The priority for repairing a link was determined on the basis of two factors: the necessity of repair and the ease of repair. The ease of repairing a link depends on the number of breaks in the link, while the necessity of repair depends on the degree of water shortage and the number of customers associated with the link.
The flow parameters obtained by damaged condition analyses were used to determine the necessity of repair and the ease of repair for each link. On the basis of these two factors, the priority for repairing each link was then established (figure 8). The links closer to the supply nodes have a higher priority for restoration. In addition, many links in the northern part of the county have high priority, even though they are away from the supply nodes, since they can cause a severe water shortage in this area. In addition, many links within Memphis also have high priority because these links serve a large population.
Burrough, P.A., (1986), "Principles of Geographic Information Systems for Land
Resources Assessment," Oxford University Press, New York, New York.
Craig, E.T., (1991), "Seismic Loss Estimates for a Hypothetical Water System,"
ASCE Technical Council on Earthquake Engineering, Monograph No. 2, American
Society of Civil Engineers, New York, New York.
Environmental Systems Research Institute (ESRI), (1989), "ARC/INFO Users
Manual," Environmental Systems Research Institute, Redlands, California.
Hwang, H., Ch'ng, A., and Hsu, H., (1992), "Seismic Fragility Analysis of
Memphis Sheahan Pumping Building," Technical Report, Center for Earthquake
Research and Information, Memphis State University.
Hwang, H., Lee, C.S., and Ng, K.W., (1990), "Soil Effects on Earthquake Ground
Motions in the Memphis Area," Technical Report NCEER-90-0029, National Center
for Earthquake Engineering Research, University at Buffalo, August 2, 1990.
Katayama, T., Kubo, K., and Sato, N., (1975), "Earthquake Damage to Water and
Gas Distribution System," Proceedings of the U.S. National Conference on
Earthquake Engineering, Ann Arbor, Michigan, June 18-20, 1975, pp. 396-405.
Sato, R., Murata, M., and Shinozuka, M., (1991), "Seismic Risk Analysis of
Water Delivery System Based on GIS," Proceedings of the Fourth International
Conference on Seismic Zonation, Stanford, California, August 25-29, 1991, Vol.
III, pp. 163-170.
Shinozuka, M., Hwang, H., and Murata, M., (1992), "Impact on Water Supply of a
Seismically Damaged Water Delivery System," Lifeline Earthquake Engineering in
the Central and Eastern US/TCLEE Council/ASCE Sessions Proceedings of the ASCE
National Convention, New York, New York, September 13-17, 1992, pp. 43-57.
Shinozuka, M., Murata, M., and Hwang, H., (1993), "Restoration Planning for
Memphis Water Delivery Network Based on Simulated Seismic Damage," Proceedings
of the 1993 National Earthquake Conference, Central United States Earthquake
Consortium, Memphis, TN, Vol. I, May 2-5, 1993, pp. 471-480.
Tanaka, S., et al., (1994), "User's Guide for Lifeline -W (II), A Program for
Connectivity and Flow Analysis of a Water Delivery System Under Intact and
Seismically Damaged Conditions," Version 1, NCEER Technical Report, (to be
A project to retrofit the U.S. Court of Appeals building in San Francisco with the Friction Pendulum System (FPS) has won the General Services Administration's (GSA) National Design Award in Engineering, Technology and Innovation. This award honors design and engineering excellence in federal buildings. The selection was made by a jury of nationally recognized design professionals in consultation with the Design Program of the National Endowment for the Arts.
The FPS was invented by Victor Zayas, president of Earthquake Protection Systems of San Francisco, California, and was tested extensively under an NCEER research project led by Michael Constantinou, professor of civil engineering at the University at Buffalo. In the research, models of buildings, bridges and floor systems equipped with the FPS were subjected to simulations of historical earthquakes on the University at Buffalo's shake table. According to Zayas, "the testing and evaluation performed at NCEER was critical in verifying the reliability of the FPS bearings."
Closed since 1989 when it was damaged by the Loma Prieta earthquake, the Court of Appeals building is one of the most ornate buildings west of the Mississippi, and is listed on the National Register of Historic Places. Retrofit of the structure was designed by Skidmore Owings and Merrill of San Francisco and was completed last spring. The project involved lifting the block-long building off its foundation so that base isolators could be installed. According to a GSA official, the FPS was chosen because it required less invasive construction work than competing technologies, and resulted in a savings of $8 million.
George Lee, NCEER Director, said that the completion of the work and the award underscore NCEER's success at transferring seismic protection technologies from laboratory to real-world applications. The award was presented March 9 at a reception in Washington, D.C.
The first seismic building code for the city of New York was unanimously passed by the city council, and on February 21, 1995 was signed into law by Mayor Rudolph Guiliani. Passage of the code was the result of an effort that was initiated by a committee of engineers, city officials, and industry and business representatives over ten years ago when New York City was reclassified from seismic risk zone 1 to 2A (on a scale of 4). Guy Nordenson, chairman of the committee, and Klaus Jacob, chairman of the geotechnical subcommittee and a member of NCEER's Research Committee, attended the official signing.
New York City's building code is based on the seismic design provisions of the Uniform Building Code (UBC) with some city-specific modifications, such as those for site factors and building separation. Seismic design requirements will apply to new construction, excluding one- and two-family dwellings. Other changes require more ductile steel beam-to-column connections, additional concrete shear walls and steel reinforcement of masonry, and more secure anchorage of precast panels. The soils factor range has been increased because of lessons learned from the 1989 Loma Prieta earthquake. The resulting recommendations were submitted to the New York City Commissioner of Buildings in April 1991, and will take effect in February 1996.
For a copy of the new seismic provisions, contact Rick Chandler, P.E., Brooklyn Borough Deputy Superintendent, Department of Buildings, phone: (718) 802-3677 or fax (718) 802-3674.
The NCEER Research Committee met February 25-26, 1995 in Buffalo, New York to make preliminary plans for the upcoming funding year (Year 10) research tasks. These plans were then presented to the Scientific Advisory Committee during its spring meeting.
The NCEER Scientific Advisory Committee met in Buffalo, New York on March 25-26, 1995 to review the research plans made by the Research Committee and to make general recommendations on the proposed program. National Science Foundation (NSF) liaison. Dr. S.C. Liu discussed recent activity impacting NSF earthquake research and provided the agency's perspective on the role of NCEER in the coming year. Parallel emphases in Year 10 are to be placed on the culmination of many ongoing projects and the development of milestone products, such as monographs, research syntheses and software.
The Research Committee will use the recommendations by the Scientific Advisory Committee to further refine its Year 10 research proposal, which will be submitted to the Scientific Advisory Committee for review and advisement at its summer meeting, scheduled for late June.
The National Science Foundation site review team, which visited NCEER headquarters October 20-21, 1994, has recommended that NCEER be funded at full levels for Years 9 and 10.
The team's mission was to advise the National Science Foundation on NCEER's plans and status for Years 9 and 10. The team was assembled to perform this mid-term review of NCEER's research and implementation activities for the period from 1991-1996. The team was generally complimentary of NCEER's research program and accomplishments, and concluded that NCEER had achieved more as a Center than would have been possible through funding individual investigators.
The site review team members included Dr. Neil Hawkins, panel chairman, University of Illinois at Urbana-Champaign; Dr. Daniel J. Alesch, University of Wisconsin at Green Bay; Dr. Jean-Lou Chameau, Golder Associates; Dr. W.D. Liam Finn, University of British Columbia; Dr. Helmut Krawinkler, Stanford University; Dr. Stephen Mahin, University of California at Berkeley; Ms. Suzanne Dow Nakaki, Englekirk and Nakaki; and Dr. William Petak, University of Southern California.
A public meeting is being planned by NCEER to examine the impact of a damaging earthquake on the financial and insurance communities of the United States and potential mitigation strategies which may be pursued to minimize loss. The Conference on Economic Consequences of Earthquakes: Preparing for the Unexpected is scheduled to be held on September 12-13, 1995 in New York City and will feature a number of prominent speakers from the earthquake, financial and insurance communities.
For additional information on the conference, please contact conference organizer Professor Barclay Jones, Cornell University, at (607) 255-6846 or via fax at (607) 255-1971. Information on pre-registration will be provided in the next issue of the NCEER Bulletin or contact Deborah O'Rourke at NCEER to be added to the announcement mailing list, phone: (716) 645-3391 or fax: (716) 645-3399.
The first update to the earthquake engineering database on CD-ROM, Earthquakes and the Built Environment Index, is scheduled to be released in June. The CD-ROM is the result of collaborative efforts between the NCEER Information Service, the Information Service of the Earthquake Engineering Research Center at the University of California at Berkeley, and the Newcastle Region Public Library in Newcastle, Australia.
The CD-ROM offers the unique opportunity to search the databases of the three participating institutions, Quakeline(, Earthquake Engineering Abstracts Database, and the Newcastle Earthquake Database, one at a time or in combination. With this update to the CD-ROM, over 100,000 records pertaining to earthquake engineering, geotechnical and socioeconomic aspects of earthquakes, and hazards mitigation in general will be available for searching. Duplication between the databases is eliminated through a unique feature of the software developed by the producer of the CD-ROM, the National Information Services Corporation (NISC) of Baltimore.
A feature added to this edition of the CD-ROM will be the capability to conduct the search process either in English or Spanish. Through the use of a "toggle switch" function of the software, a user can decide to have search screens and help screens appear either in English or Spanish. All database records will continue to appear in English.
The CD-ROM is available for sale from the producer, NISC (phone: (410) 243-0797) for a yearly subscription price of $295.00 with updates every six months. A thirty day free trial subscription is also available and is an excellent way to sample the power and unique searching opportunity of this database compilation. Any inquiries concerning the CD-ROM can be directed to the NCEER Information Service, phone: (716) 645-3377; fax: (716) 645-3379 or email at nernceer@ubvms. cc.buffalo.edu.
NCEER's strong motion database, STRONGMO, is now accessible over the World Wide Web (WWW) through programs such as NCSA's MOSAIC, free to educational institutions, or NETSCAPE, from a commercial firm called netcom. The address for NCEER's strong motion database is Lamont-Doherty Earth Observatory's World Wide Web server (http://www.ldeo.columbia.edu).
For example, MOSAIC users can arrive at the correct address by performing the following steps. In the program, at the main window called "NCSA Mosaic: Document View," choose the word FILE at the upper left and a pop-up menu with about 17 options will appear. Choose "Open URL" (URL stands for Universal Resource Locater). A small window called "NCSA Mosaic: Open Document" will open up. Now, type the address http://www.ldeo.columbia.edu in the blank space following "URL To Open:". Next, click on the open button and the original window will now be the Lamont-Doherty Earth Observatory Mosaic Home Page. Once at Lamont's Home Page, look for -NCEER Earthquake Strong Motion Database (Noel Barstow)- and from there, the following features can be accessed:
Other ways to access STRONGMO are as follows:
To connect to a computer at LDEO, type:
A User's Guide to STRONGMO, a manual which describes the strong motion data base, is available either through UNIX anonymous ftp in the directory ~ftp/nceer (ftp lamont.ldeo.columbia.edu or ftp 184.108.40.206); login: anonymous; password: your complete e-mail address; or from NCEER Publications, report number NCEER-90-0024, $10.00.
Contact Noel Barstow at Lamont-Doherty Earth Observatory with comments and questions regarding STRONGMO. She can be reached by phone at (914) 365-8477; fax at (914) 365-8150 or via email at email@example.com or firstname.lastname@example.org. edu.
NCEER technical reports are published to communicate specific research data and project results. Reports are written by NCEER-funded researchers, and provide information on a variety of fields of interest in earthquake engineering. The proceedings from conferences and workshops sponsored by NCEER are also published in this series. To order a report reviewed in this issue, fill out the order form and return to NCEER. To request a complete list of titles and prices, contact NCEER Publications, University at Buffalo, Red Jacket Quadrangle, Box 610025, Buffalo, New York 14261-0025, phone: (716) 645-3391; fax: (716) 645-3399; or email: email@example.com.
Proceedings of the International Workshop on Civil Infrastructure Systems: Application of Intelligent Systems and Advanced Materials on Bridge Systems Edited by G.C. Lee and K.C. Chang, 7/18/94, NCEER-94-0019, 476 pp., $40.00
The theme of this proceedings volume is the application of intelligent systems and advanced materials to bridges and elevated road systems, in the context of civil infrastructure systems development and renewal in the U.S. and Taiwan. The volume offers twenty-five technical papers, which cover a wide variety of topics. Two papers provide overviews of the 1994 state of the art in bridge design and construction in these two countries. A third reviews 1994 civil infrastructure research programs in the U.S. The remainder discuss new technology and methods, including advance shoring for span-by-span bridge construction, cable-stressed steel bridges, active and hybrid control systems, bridge monitoring systems, high performance concrete and high performance steel, concrete bridges, intelligent paint inspection systems, smart and self-compactable concretes, and knowledge based design systems.
Proceedings from the Fifth U.S.-Japan Workshop on Earthquake Resistant Design of Lifeline Facilities and Countermeasures Against Soil Liquefaction Edited by T.D. O'Rourke and M. Hamada, 11/7/94, NCEER-94-0026, 782 pp., $40.00 This proceedings volume presents forty-seven technical papers and four working group summaries. Nine of the papers are case studies of liquefaction and related phenomena observed during recent earthquakes in Japan and the U.S. Thirteen papers present analytical or experimental research into the physical mechanisms of soil liquefaction. Six papers study the dynamic response of underground structures to liquefied ground. Case studies of techniques for the mitigation of liquefaction-induced damage are presented in seven papers. The final group of twelve papers presents a variety of studies which deal with the performance of lifelines, (especially buried pipelines) subjected to ground liquefaction. This last group of papers includes observations made during recent earthquakes; analytical and experimental studies; and socioeconomic studies of the secondary losses and social disruption caused by failed lifelines.
Experimental and Analytical Study of Low-Cycle Fatigue Behavior of Semi-Rigid
Top-and-Seat Angle Connections
G. Pekcan, J.B. Mander and S.S. Chen, 1/5/95, NCEER-95-0002, 134 pp., $15.00
One common type of existing structure investigated to a limited extent in the buildings area is steel frames with semi-rigid connections. In previous studies, analytical models have been developed, the effects of floor slabs and masonry infills have been studied, and parametric response analyses have been performed. This report summarizes work on the low-cycle fatigue behavior of a common type of semi-rigid connection, those made of top and seat angles.
Nineteen tests were performed using various load histories and they showed that the hysteretic energy-life and rotation-life models are applicable for this type of connection. The analysis showed that if the plastic hinge rotations are kept below 2%, the connections can sustain at least fifty cycles of complete load reversals. The report contains a valuable database on the cyclic behavior of one type of semi-rigid connection.
NCEER-ATC Joint Study on Fragility of Buildings
T. Anagnos, C. Rojahn and A.S. Kiremidjian, 1/20/95, NCEER-95-0003, 116 pp.,
This report provides improved damage-motion relationships that can be used in regional earthquake damage and loss studies. Three main areas for modification of the existing ATC-13 damage probability matrices were investigated. The first was to develop detailed descriptions of the original 40 building classes defined in ATC-13. These descriptions clarified assumptions made regarding the load carrying system and the standard design practices. The second approach for modifying the motion damage relationships was through collecting existing data. It was found that these data are not particularly useful because they were collected under different formats and with different interpretations by the individuals gathering the data. In addition, ground motions were not available for the majority of the data.
The third modification considered the development of fragility formulations based on the information from the ATC-13 damage probability matrices. For that purpose, the original mean and 90% expert opinion values of damage at each intensity level were used to develop fragility curves for all 40 building classes. Then a lognormal function was fitted through the fragility curve to enable easy implementation of these fragility curves. These curves can be easily implemented in large regional damage and loss estimation studies.
Nonlinear Control Algorithms for Peak Response Reduction
Z. Wu, T.T. Soong, V. Gattulli and R.C. Lin, 2/16/95, NCEER-95-0004, 96 pp.,
A linear quadratic regulator has been used extensively in many control systems designed for structural control applications due to its stability and robustness. Recent results obtained from simulation, model experiments, and full-scale structural applications, however, show that it is difficult to employ linear feedback control laws to produce a significant peak response reduction when the peak response occurs during the first few cycles of the time history. In this report, a class of nonlinear control algorithms are proposed which can provide improved peak response control performance. Through extensive simulation studies and experimental verification in the laboratory using a model structure, it is shown that these nonlinear control laws can significantly improve peak response reduction under the same constraints imposed on the control resources as in the linear quadratic regulator case.
Technical Report Order Form Name .............................................................. Address ........................................................... City/State/Zip ..................................................... Country ........................................................... Telephone____________________Telefacsimile Shipping Options: Third Class - U.S. First Class - U.S (no additional charge) (add $3 per title) Surface International Airmail International (add $5 per title) (add $9 per title) Report Number Authors Price ......................... Shipping ...................... Total ........................ For a complete list of technical reports, call NCEER Publications at (716) 645-3391; fax: (716) 645-3399. Make checks payable to the "Research Foundation of SUNY"
SEAONC Spring Seminar Series:
The Great Hanshin Earthquake Disaster
The Structural Engineers Association of Northern California is sponsoring The Great Hanshin Earthquake Disaster: What Worked and What Didn't? Engineering Implications of the January 17, 1995 Hyogo-Ken Nanbu Earthquake on May 18 and 25, 1995, at the Henry J. Kaiser Center in Oakland, California. Eight engineers and scientists will explore these themes and relate first-hand experiences of the earthquake. For registration forms and information, contact SEAONC at 74 New Montgomery St. #230, San Francisco, California 94105-3411; phone: (415) 974-5147 or fax: (415) 764-4915.
Response of Concrete Bridges in Recent Earthquakes
Response of Concrete Bridges in Recent Earthquakes is a technical session that will be held during the ACI spring convention, March 14-19, 1996, in Denver, Colorado. It is sponsored by ACI Committee 341, Earthquake-Resistant Concrete Bridges. Presentations on findings based on field investigation, testing, and/or analysis of concrete bridge response during recent earthquakes, and the effect of these earthquakes on bridge seismic retrofit and design are being solicited. Potential contributors must submit the following: paper title; author(s) full name, title, affiliation, address, telephone and fax numbers; presenting author's name; and an abstract between 200-300 words. Abstracts must be received by August 15, 1995. For more information and/or to send abstracts, contact Dr. M. Saiid Saiidi, Civil Engineering Department (258), University of Nevada, Reno, NV 89557; phone: (702) 784-4839 or fax: (702) 784-4466.
Eighth Annual Emergency
The Eighth Annual Emergency Preparedness Conference will take place October 17-19, 1995 at the Sheraton Landmark Hotel in Vancouver, British Columbia. The purpose of the conference is to raise the level of emergency preparedness by promoting awareness; providing information, tools and solutions to problems; sharing experiences; showcasing technologies; and creating networking opportunities. For more information contact the Emergency Preparedness Conference, Marie Rogan, Conference Registrar, BC Rehab, 700 West 57th Avenue, Vancouver, BC, Canada, V6P 1S1; phone: (604) 321-3231; fax: (604) 321-7833. Seismological Society of America,
Eastern Section Annual Meeting
The Seismological Society of America, Eastern Section, will hold its annual meeting at the IBM Palisades Executive Conference Center in Palisades, New York on October 12-13, 1995. Abstracts are currently being accepted and should be sent to Nol Barstow, L-DEO, Route 9W, Palisades, New York 10964; phone: (914) 365-8477 (8486), fax: (914) 365-8150, email: firstname.lastname@example.org. Abstracts are due by September 8, 1995.
Pacific Conference on Earthquake Engineering
The Pacific Conference on Earthquake Engineering (PCEE '95) will take place November 20-22, 1995 at the University of Melbourne, Melbourne, Australia. The conference will cover such topics as intraplate seismicity and zonation, soil response and soil-structure interaction, design in areas of low seismicity, seismic isolation, building codes, insurance, earthquake disaster mitigation, lifelines, retrofitting of existing structures, steel/concrete/timber/URM structures, nonstructural elements and components, and recent large/damaging earthquakes. For more information, contact Barbara Butler, PCEE '95, PO Box 829, Parkville, Victoria 3052 Australia; phone: (+61) 3-344-6712 or fax: (+61) 3-344-4616.
Geologic Hazards Slide Sets Available
The National Geophysical Data Center has several geologic hazards slide sets available for purchase. Topics include the January 17, 1994 Northridge, California Earthquake; the Major Tsunamis of 1992 - Nicaragua and Indonesia; the Hokkaido Nansei-Oki Tsunami, July 12, 1993; Earthquakes (various sets); Tsunamis (various sets), and Volcanoes (various sets). For a complete listing and prices, contact the National Geophysical Data Center, NOAA, Code E/GC1, Dept. 953, 325 Broadway, Boulder, CO 80303; phone: (303) 497-6607; fax: (303) 497-6513, or email: info@ngdc. noaa.gov.
The Spitak Earthquake CD-ROM, developed as a cooperative effort between Russia and the United States, was compiled to provide seismologists with a complete set of data for the devastating earthquake that occurred in Armenia on December 7, 1988. This set consists of textual and graphical information about the earthquake, a DOS and Microsoft Windows menu for accessing the data, and a User Manual which discusses the data and explains how to use the access software to display and obtain useful information. For further technical information, contact Allen M. Hittleman (USA) at phone: (303) 497-6591, fax: (303) 497-6513; or email: email@example.com or Yuri Tyupkin (Moscow, Russia) at phone: (095) 930-05-46, fax: (095) 930-55-09 or email:
The Spitak Earthquake CD-ROM is $71.00 (product number 1131-A27-001). To order, contact the National Geophysical Data Center, NOAA, Code E/GC1, 325 Broadway, Dept. 958, Boulder, CO 80303; phone: (303) 497-6277; fax: (303) 497-6513, or email: firstname.lastname@example.org.
Results on Existing Buildings
The Seismic Safety Commission of the State of California has released a new report entitled Review of Seismic Research Results on Existing Buildings by Jack Moehle, Joseph Nicoletti and Dawn Lehman, developed as part of its Seismic Retrofit Practices Improvement Program. The report describes the state of knowledge of the earthquake performance of nonductile concrete frame, shear wall, and infilled buildings. It then summarizes 90 recent research efforts with key results and conclusions in a simple, easy to access format written for practicing design professionals. Copies of the report (No. SSC 94-03) are available for $20.00 through the Seismic Safety Commission, 1900 K Street, Suite 100, Sacramento, CA 95814; phone: (916) 322-4917.
International Conference and Exposition on Natural Disaster Reduction
The International Conference and Exposition on Natural Disaster Reduction will take place March 5-8, 1996 in Washington, D.C. Sponsored by the American Society of Civil Engineers (ASCE), the objective of the conference is to discuss the role of engineers, scientists and others, in preventing, mitigating, preparing for and recovering from natural disaster impacts on the built and natural environments, with consideration for socio-economic, political, public health and institutional interfaces. Disasters to be considered include earthquakes, tsunamis, volcanoes, hurricanes/cyclones/ typhoons, tornadoes, floods, landslides, wildfire, droughts, and multi-hazards. Disaster elements to be considered include: engineering for safety and economy, risk management, preparedness, mitigation, response, recovery, education/ training, institutional, socioeconomic, environmental, research and implementation.
For more information, contact George L. De Feis, ASCE, 345 East 47th Street, New York, NY 10017, phone: (212) 705-7290 or fax: (212) 705-7975.
National Center for Earthquake Engineering Research
State University of New York at Buffalo
Red Jacket Quadrangle
Buffalo, NY 14261-0025
Phone: (716) 645-3391
Fax: (716) 645-3399
Editor: Jane Stoyle
Illustration and Photography: Hector Velasco
Production and Mailing List: Laurie McGinn
N. Barstow, Lamont-Doherty Earth Observatory
I.G. Buckle, NCEER
C. Costantino, City University of New York
H. Hwang, University of Memphis
C. Kizis, NCEER Information Service
M. Shinozuka, Princeton University
Some of the material reported herein is based upon work supported in whole or in part by the National Science Foundation, the New York State Science and Technology Foundation, the U.S. Department of Transportation and other sponsors. Any opinions, findings, and conclusions or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the views of NCEER or its sponsors.