HR: 08:30h
AN: OS21A-03 INVITED     [PDF]
TI: NEES Tsunami "Product" Example : Standards and Guidelines for Construction of Coastal Structures.
AU: * Synolakis, C E
EM: costas@usc.edu
AF: Univesity of Southern California, Department of Civil Engineering, Los Angeles, CA 90089 United States
AU: Eskijian, M
EM: ESKIJIM@slc.ca.gov
AF: California State Lands Commission, Marine Facilities Division, Long Beach, CA 90802 United States
AU: Borrero, J C
AF: Univesity of Southern California, Department of Civil Engineering, Los Angeles, CA 90089 United States
AU: McCarthy, D
EM: dmccarth@quiknet.com
AF: California Seismic Safety Commission, 1755 Creekside Oaks Drive, Sacramento, CA 95833 United States
AB: In the past decade, considerable progress has been achieved in improving tsunami inundation models. In addition to the availability of high qualify field survey data, comparisons with small and larger scale laboratory data as in NSF's Friday Harbor workshop (Yeh et al., 1996) have allowed validation of inundation predictions. By contrast, there has been far less progress in predicting forces or in translating inundation predictions to standards and guidelines. One example of addressing this issue is in a companion FEMA study undertaken jointly by the Marine Faciltiies Division of the State Lands Commission (CSLC) with USC to develop standards and guidelines for marine terminals in Los Angeles, Ventura and Orange Counties in Southern California, referred to as MOTEMS. Poorly or inadequately designed oil terminals can pose significant risks to public safety; SLC regulates the operation of marine facilities in California waters and and has the mandate to adopt performance standards for the construction and maintenance of these terminals. Prior to this study, no standards existed for seismic or tsunami hazards. The consortium comprised of USC, SLC and LLNL first completed a probabilistic hazard assessment to suggest combined probabilities for ground accelerations from different events that might affect marine terminals in the Southland. Then both tsunamigenic faults and offshore landslide-prone areas were identified and the associated runup modeled (Borrero, 2002). SLC then integrated the seismic and tsunami results and developed engineering standards for marine oil terminals, now in the final stages to state adoption as regulations (Eskijian et al, 2003). While the tsunami-specific standards allow for safer design of marine facilities, they are currently stated in terms of expected tsunami wave heights and return periods. Consulting engineers and the CSLC have to make their own assessments as to the adequacy of resulting force predictions for the design tsunami heights, as well as impact loads from ships and floating debris. While small scale data on forces on piles and walls have been obtained in collaborative NSF-funded studies (Harry Yeh, pers. comm.), predictions from these data sets at prototype scales have yet to be validated. Also, no predictions for tsunami forces from numerical models have yet been compared with lab data. Large scale laboratory experiments planned under NEES will allow for the validation of numerical predictions for wave velocities and forces, the extrapolation from small scale lab experiments, and the translation of force predictions to construction standards. It is anticipated that the latter will include performance guidelines for the design of seawalls, wharfs, piers, and structures to mitigate both direct and indirect tsunamigenic losses. References Borrero, J.C., 2002, {\it Analysis of Tsunami Hazards in Southern California}, PhD thesis, USC, 262p. Eskijian, M.S. Heffron, R.E., Dahlgren, T., 2003.. {\it Engineering Standards for Marine Oil Terminals}, in Submarine Landslides and Tsunamis, Yacliner, A. et al (eds), NATO Science Series, Kluwer Academic Publishers. Yeh, H. Liu, P.L-F., Synolakis, {\it Long Wave Runup Models}, World Scientific. {\it Marine Oil Terminal Engineering and Maintenance Standards}, (MOTEMS), July 2003, published by the California State Lands Commission.
DE: 3384 Waves and tides
DE: 4251 Marine pollution
DE: 4564 Tsunamis and storm surges
DE: 6615 Legislation and regulation
SC: Ocean Sciences [OS]
MN: 2003 Fall Meeting