Experiments On Seismic Performance Of Pile-soil-pier Interaction System

Now the difficulty in the research on soil-structure interaction proble m is lackingthe necessary practica l data．There fore there is a lot of uncertainty while ana lyzing ininteraction，1imited its applicatio n in actua l engineering design．To compensate fordefic ie ncies in this re gard, based on the Nationa l Natural Sc ience Foundatio n of thepile-soil med ium Nonlinear Dyna mic C oupling effect mec hanis m ana lys is and remotecollaborative pilot study (NO.50808078), this paper studied the1:4majority feetmodel test of bridge columns research under cons ideration of soil-structureinternaction. Consider near-fie ld seis mic effect on a rigid fo undation and steel pipepile group foundation cyc lic loading test, the comparative ana lys is of bridge columnsin both cases the seis mic performance indicators. This paper is divided into fo urchapters, the ma in content is organized as fo llows:1. Introductio n of the research status of the pile-soil-structure interaction, inview of the present stage of p ile-soil-structure interaction theory, defic ienc y of thetest method research, put forward the necessity of the research content and theresearch.2. Foundatio n parameters measured by the test methods, inc lud ing so il dens ity,mo isture content, void ratio, compress ion modulus; under different excitatio nintens ities obtained through the power vibratio n test determine s ite class single-holemethod for determination of shear wave veloc ity of the site; pile Cap horizo nta ldisplace ment and angular disp lacement frequency response curve, can be regarded asthe foundatio n dyna mic stiffness, damping ratio and other para meters, to provide thenecessary data for subsequent modeling analys is, and analyze the different excitatio nstrength parameters of dynamic soil properties affected.3. Introductio n of indoor1/4pier mode l test design, model making, mechanica lproperties, test equip ment, arrange ment o f data measuring e le ment and thedetermination of loading s ystem.4. Two model of bridge pier column test, contrast analys is in the near-fieldseis mic loading syste m, cons ider the seis mic performance of brid ge pier pile-soil-bridge pier interaction syste m and fully rigid foundatio n, inc lud ing p iers hystereticbehavior, stiffness degradation, skeleton curve is ana lyzed taking into account;period ic structure characteristics of soil-structure interaction exte ns ion ratio and different loading stage structure characteristic period extended trend; a t the same timecontrast variation o f two pier column reinforcement strain, and strain of stee l tubeduring loading p ile. In cond ition o f soil will reduce earthquake on the upper structuresystem, the stiffness degradation, stra in of steel bar and the structure syste m of thebasic cyc le is ind icated by the rigid ground assumption of upper structure syste mdesign basically will be on the safe side; but the mo ment of the pile-soil syste m isrelative ly weak, the underground part of the actua l structure of the syste m willprecede the superstructure and destruction, whic h according to the rigid groundassumption will be unsa fe, so it is necessary to consider the influence of pile-so ilinteraction.