<ETD> Submission Form - Cataloger

Name:
Alan F. Rauch

Email address:
Not Provided

URN:

Title: EPOLLS: An Empirical Method for Prediciting Surface Displacements Due to Liquefaction-Induced Lateral Spreading in Earthquakes

Date of defense:
May 5, 1997

Date of approval:
May 27, 1997

Document Type:
Doctor'ate Dissertation

Degree:
Doctor of Philosophy in Civil Engineering

Department:
Civil Engineering


Abstract


In historical, large-magnitude earthquakes, lateral spreading has been a very damaging type of ground failure. When a subsurface soil deposit liquefies, intact blocks of surficial soil can move downslope, or toward a vertical free face, even when the ground surface is nearly level. A lateral spread is defined as the mostly horizontal movement of gently sloping ground (less than 5% surface slope) due to elevated pore pressures or liquefaction in undelying, staturated soils. Here, lateral spreading is defined specifically to exclude liquefaction failures of steeper embankments and retaining walls, which can also produce lateral surface deformations. Lateral spreads commonly occur at waterfront sites underlain by saturated, recent sediments and are particularly threatening to bur transportation networks. While the occurrence of soil liquefaction and lateral spreading can be predicted at a given site, methods are needed to estimate the magnituted of the resulting deformations.

In this research effort, an empirical model was developed for prediciting horizontal and vertical surface displacements due to liquefaction-induced lateral spreading. The resulting model isled "EPOLLS" for Empirical Prediction Of Liquefaction-induced Lateral Spreading. Multiple linear regression analyses were used to develop model equations from a compiled database of historical lateral spreads. The complete EPOLLS model is comprised of four components: (1) Regional-EPOLLS redicting horizontal displacements based on the seismic source and local severity of shaking, (2) Site-EPOLLS for improved predictions with the addition of data on the site topography, (3) Geotechnical-EPOLLS using additional data from soil borings at the site, and (4) Vertical-EPOLLS for predicting vertical displacements. The EPOLLS model is useful in phased liquefaction risk studies: starting with regional risk assessments and minimal site information, more precise predictions of displacements can be made with the addition of detailed site- specific data. In each component of the EPOLLS model, equations are given for predicting the average and standard deviation of displacements. Maximum displacements can be estimated using probabilities and the gamme distribution for horizontal displacements or the normal distribution for vertical displacements.

Keywords:
ground deformation, lateral spreading, lifeline damage, slope stability, soil liquefaction

Availability:
VT ONLY

Public URL:
http://scholar.lib.vt.edu/theses/public/etd-219182249741411/new_etd-title.html


List of attached files

File NameSize (Bytes)
Apxa.pdf73,266 Bytes
Apxb.pdf51,966 Bytes
Apxc.pdf74,852 Bytes
Apxd.pdf273,044 Bytes
Apxe.pdf41,090 Bytes
Chp01.pdf44,794 Bytes
Chp02.pdf81,367 Bytes
Chp03.pdf167,534 Bytes
Chp04.pdf181,402 Bytes
Chp05.pdf114,652 Bytes
Chp06.pdf625,556 Bytes
Chp07.pdf196,278 Bytes
Chp08.pdf322,463 Bytes
Chp09.pdf902,252 Bytes
Chp10.pdf203,349 Bytes
Chp11.pdf211,865 Bytes
Chp12.pdf54,138 Bytes
Etd.pdf122,504 Bytes
Refer.pdf60,242 Bytes
Vita.pdf5,558 Bytes


[ETD main page] [Search ETDs][etd.vt.edu] [SCP home page] [library home page]

Send Suggestions or Comments to webmaster@scholar.lib.vt.edu


[ETD main page] [Search ETDs][etd.vt.edu] [SCP home page] [library home page]

Send Suggestions or Comments to webmaster@scholar.lib.vt.edu