ASSESSMENT OF ANTI-LIQUEFACTION GROUTING REINFORCEMENT EFFECT OF TUNNEL FOUNDATION BASED ON EARTHQUAKE- INDUCED DEFORMATIONS CONTROL
HUANG Yu1，2，JIN Chen1，2，ZHUANG Zhijing1，2
(1. Department of Geotechnical Engineering，Tongji University，Shanghai 200092，China；2. Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education，Tongji University，Shanghai 200092，China)
Abstract：At present，there are two kinds of theories for anti-liquefaction，i.e. prevention of excess pore water pressure generation and development，and reduction of liquefaction-induced deformations. Up to now，most of researches have paid more attentions to the former，while the latter one has not been fully analyzed. Therefore，focused on the latter theory for anti-liquefaction，by using a cyclic elastoplastic constitutive model，liquefaction analysis of a water intake and outlet tunnel of a power plant in Shanghai is carried out by means of finite element method based on Biot¢s consolidation theory. A numerical simulation method for earthquake-induced liquefaction deformation is proposed under plane strain conditions to assess anti-liquefaction grouting effect. The dynamic responses including displacements，accelerations，and excess pore water pressures of tunnel foundation before and after reinforcement are analyzed. It is proved that the liquefaction deformations of the tunnel foundation can be effectively reduced by the proper anti-liquefaction measures. Some scientific suggestions for aseismic designs of this project are proposed based on the results of numerical simulation，and they can provide good references for liquefiable ground treatment of other similar projects.
