Principal
Investigator(s) and Institution(s)
Michael S. Higgins, MCEER
Objective
and Approach:
An
international workshop on lessons learned from recent earthquakes will be
held November 6 - 10, 2000. The
host institution will be the KGM, the Turkish Road Directorate, a Turkish
organization equivalent to the USDOT's FHWA.
It will provide a forum for the discussion and exchange of
information about recent and future developments in the mitigation of
seismic effects on transportation structures, and the promotion of
international cooperation and research in this area.
The Kocaeli
(8/17/99) and the Duzce (11/12/99) earthquakes in Turkey provide the
opportunity for MCEER to study important lessons about how the United
States' highway bridges and structures will perform in major earthquakes.
The Kocaeli and Duzce earthquakes were both along the North Anatolian
Fault Zone. This fault zone
has characteristics and behavior very similar to California's San Andreas
fault. Furthermore, in recent
years the Turkish bridges were designed to AASHTO specifications, which is
the specification also used for US bridges.
Topics
pertinent to MCEER research under this FHWA contract (DTFH61-98-C-00094-
Project 094) that will be discussed during the workshop include:
1)
Near
fault effects- After several destructive earthquakes in metropolitan
areas, it has been recognized that structures near the active fault may
experience a displacement pulse of relatively long period and high
amplitude. Such pulses could
be extremely detrimental to flexible structures (those with a long natural
period). These types of
structures include isolated bridges and long span bridges.
Under its present FHWA Project 094 contract (Task C2-1), MCEER is
investigating near fault effects. In
both of the Turkey earthquakes, infrastructure, including bridges,
situated in near fault zones were extensively damaged.
Consequently, lessons learned during the Turkey earthquakes are
invaluable to the MCEER research on near fault effects.
2)
Earthquake
protective systems- Multiple bridges in Turkey that utilized isolation
systems were subjected to strong ground motions during these earthquakes.
These systems performed with varying degrees of success. The lessons learned by the performance of these devices is
crucial for verifying theoretical assumptions made in MCEER tasks related
to earthquake protective systems. Specifically,
Task D1-1 is focused on reviewing the performance of isolated bridges that
have been subjected to strong ground motions. Presently on-going Tasks
D1-2 and D2-1 and potential future Tasks D2-2 and D2-3 all relate to
developing improved earthquake protective systems.
In addition, Task D3-1 is producing an interim design manual
covering these types of devices. The
Principal Investigators (PIs) for all of these tasks will benefit by a
better understanding of how these systems performed in the subject
earthquakes.
3)
Hazard
and risk analysis- an important part of MCEER's FHWA Project 094 contract
is to refine, extend, and improve the state of practice for hazard and
risk analysis (Task B). The
KGM recognized the hazard that their structures may be subjected to strong
ground motions resulting from earthquakes.
This is evident due to their use of earthquake protective systems
and other earthquake resistant design features.
MCEER's PIs on Task B will benefit from determining how the KGM
screened their structures for retrofit or improved design and what lessons
they learned during the subject earthquakes.
4)
Geotechnical
issues related to bridge foundations- several subtasks under MCEER's
present FHWA Project 094 contract relate to the performance of bridge
foundations when subjected to strong ground motions. Subtasks C2-1, C2-2 and all subtasks under Task E investigate this
topic area.The subject
workshop will spend time focusing on lessons learned in this topic area
during the Turkey earthquakes, which may improve the future direction of
these tasks.
5)
Other
topic areas of interest- the Turkey earthquakes also offer the opportunity
to review several other topic areas of importance to America's highway
system. For instance
invaluable lessons were learned regarding the performance of tunnels,
precast prestressed concrete, and response techniques. Tunnels were an
important part of another MCEER FHWA contract (DTFH 61-92-R-00106- Project
106). Furthermore, precast prestressed concrete is now a major form of
construction for many bridges across the United States. This is also a
major form of construction in Turkey. It is important to learn how this
type of construction performs in an earthquake.
Also pre-earthquake and post-earthquake response techniques were
included in the retrofit manual under the Project 106 contract. Turkey was
recognized for being successful at both of these aspects and understanding
the response plan of Turkish engineers is important to verify the results
of Project 106. To most effectively meet the objectives of MCEER's present
FHWA Project 094 contract, it is important for MCEER to learn about these
topic areas to ensure there are no problems in the retrofit manual and to
provide input to the future direction of research.
Since
workshop attendance by MCEER will benefit multiple tasks of its present
Project 094 contract as outlined above, funds provided under this task
will be used for the travel and accommodation of 5 members of the U.S.
delegation who were selected based on their expertise.
These members will be responsible for reporting pertinent
information to the Research Committee, who will take the information into
consideration when discussing the future direction of research conducted
under the contract.
Anticipated Start Date and Duration
October 1, 2000 –
5 Months
08/00
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