Prioritizing SPEBI. Computer Files File Name*Description Bridgepostearthquake.mdbProgram file. AprilWinBoltsInAccess.mdbBridge data file. Since this data
Computer Files File Name*Description
Bridgepostearthquake.mdbProgram file.
AprilWinBoltsInAccess.mdbBridge data file. Since this data is
updated at least annually, care should be taken to have the most
current data that is available. R11 Seismic Vulnerability.xlsThis
file contains Region 11 (NYC) seismic vulnerability information.
Except for changes resulting from major bridge rehabilitations and
replacements, the information is fairly static. However, if
necessary, this file can be edited to make updates. iconEQ.icoThis
is a graphic file used to start the program. PBDA Form.pdf SPEBI
Form.pdf DSR Form.pdf user manual.pdf Arrow5.gif Calendar.jpg
Globe.jpg Quake.jpg Run.jpg These are graphic files used by the
program. *In order for the program to function, the files name must
be named precisely as indicated.
Slide 3
Computer Program
Slide 4
Slide 5
Slide 6
Generated List
Slide 7
Region 11 uses VRs
Slide 8
Earthquake Notification Service (ENS)
Slide 9
Earthquake Response Plan (ERP)
Slide 10
Response Levels
Slide 11
Staff reponsibilities If an earthquake occurs during normal
working hours, All employees shall make themselves available for
possible assignment and immediately begin to prepare for
deployment. Fuel up vehicles; check phone, camera and flashlight
batteries; gather maps, manuals, reporting forms, etc.; check
two-way radios; pick up basic tools (e.g., tape measure).
Preliminary Bridge Damage Assessments (PBDAs) will begin as soon as
possible after the event, starting with pre-defined priority
routes. If there are incoming damage reports, the RE may consider
adjusting the response accordingly. In the event of a strong
earthquake, DOT office buildings may need to be evacuated and
assessed for damage. When preparing local procedures, an alternate
site should be designated as a staging area, for use when the
regular facilities are not accessible. If an earthquake occurs
while employees are not at work, DOT staff will respond as follows:
Prepare to report to work if called and await a phone call for
assignment, If possible, contact supervisor.
Slide 12
Prioritizing SPEBIs PBDA reports Initial reports from the media
or the general public Structural vulnerability. Seismic
vulnerability ratings may be available for certain bridges but at
the time of this report, because of competing priorities, not all
bridges have been rated for seismic vulnerability. For this reason,
it will not be possible to use them consistently on a statewide
basis. Region 11, however, has rated al bridges in NYC and these
ratings should be used to prioritize post- earthquake bridge
inspections. The program presented in Appendix C has provisions for
prioritizing post-earthquake bridge inspections according to these
ratings. Among other factors, NYSs vulnerability assessment process
uses design criteria (year built is used as an indicator of design
sufficiency) to determine a vulnerability rating (VR-S). Structural
characteristics that increase the likelihood of failure from an
earthquake include: superstructure discontinuities (simply
supported spans instead of a superstructure with continuity), skew
angle, bearing type and height, lack of lateral bracing,
deteriorated condition (as reflected in the condition ratings
especially the primary and secondary structural members), seat
length and width, lack of restraint from lateral displacement,
vulnerable structure type (e.g., trusses), redundancy, poor seismic
detailing of concrete reinforcement, etc. Mode of Failure. Although
the VR is intended to anticipate bridges that might fail
catastrophically, the same criteria can be used for planning
post-earthquake procedures since it is very possible that and
earthquake can induce damage may make failure imminent, even though
the earthquake itself did not take the bridge down. Bridges with a
failure mode labeled as catastrophic should be kept higher on the
prioritized list of bridge inspections than a bridge whose failure
would not be considered catastrophic. Geological vulnerability.
Bridges founded on granular soil in an area with a high water table
may be at risk of failure from soil liquefaction if ground shaking
is severe. This possibility is most likely in coastal settings,
although experts feel that an earthquake with a magnitude M6.0
would be required to initiate liquefaction in NYS. Slope failures
and lateral spread are other potential consequences. Flagged
conditions. Since the conditions identified by these red or yellow
structural flags can compromise a bridges performance in an
earthquake, it is important to consider the presence of flags when
prioritizing. The Departments database of flagged bridges is
dynamic; it changes almost daily, depending on findings of bridge
inspectors. It might be necessary for the RSE to use personal
knowledge to supplement computer generated lists. Condition.
Inspection prioritization tools used on the west coast are
frequently based on the assumption that a bridge is in the same
condition that it was in when it was designed and built. This is
often not the case for NYS bridges. Since the general population of
bridges is older, there is usually more deterioration, such as
corrosion and fatigue, and this can have an impact on seismic
performance. In addition, repairs or modifications from original
construction could have been made. For instance, end diaphragms of
steel bridges help transfer lateral loads to the substructure. If
these have section loss due to rust, they cannot effectively
perform that function. Elements with condition ratings between 1
and 3 are in poor condition due to deterioration or are not
functioning as designed. These elements are more likely to be
damaged in an earthquake and bridges with them should be placed
higher on the list of bridges to be inspected. Structural members
considered secondary may, in fact, be very important with respect
to seismic performance. Structures carrying essential utilities
would also be considered more important than a comparable bridge
without utilities. Consideration of road closures, construction
project, proximity of bridges to one another.
ERP Terminology Preliminary Bridge Damage Assessment (PBDA): A
cursory assessment of a bridges condition by residency or other
operational staff. The time required is whatever time is needed to
get out of the vehicle, walk the bridge to look for irregularities,
quickly look underneath, and report findings on one line of a
report. The objective is to obtain an initial understanding of the
earthquakes impact on the highway network. Special Post-Earthquake
Bridge Inspection (SPEBI): A detailed bridge inspection led by a
professional engineer, focusing on the structures seismic response
and any seismically sensitive details. Special access is provided
if necessary. Daily Summary Report (DSR): A daily compilation of
SPBDA and PEBI findings. The RSE will submit a DSR consisting of
results from all SPEBIs from all TLs to the Director Office of
Structures.