In this study, an experimental investigation program on a newly proposed seismic isolation technique, namely “Geotechnical Seismic Isolation (GSI) system”, is conducted with an aim of simulating its dynamic performance during earthquakes. The testing procedure is three-fold: (1) A series of cyclic simple shear tests is conducted on the key constituent material of the proposed GSI system, i.e., rubber-sand mixture (RSM) in order to understand its behavior under cyclic loadings. (2) The GSI system is then subjected to a series of shaking table tests with different levels of input ground shakings. (3) By varying the controlling parameters such as percentage of rubber in RSM, thickness of RSM layer, coupled with the weight of superstructure, a comprehensive parametric study is performed. This experimental survey demonstrates the excellent performance of the GSI system for potential seismic hazard mitigation.

In order to understand the soil-structure interaction, we were doing the excitation test about 1:4 scaled steel frame-raft foundation model in the soil bin. The test was through changing the stiffness of the superstructure respectively. We inputting Gaussian white noise measured vibration period, dynamic response with EL and Taft wave show the shock absorption effect of the soil. Finite element software sap2000 simulated rigid foundation on the dynamic response analysis on the steel frames. We found that there are some differences about the natural period, the upper structural stiffness greater the additional period is longer. Soil has a shock absorbing effect with the steel frame, the effect mainly come from the change of structure stiffness. Because of the soil-structure interaction, peak acceleration of the top storey is reducer when steel framework excitation on the soil bin than on rigid foundation, and peak displacement of the top storey is increased.

The paper centers on research, application and promotion of a new seismic isolation layer technology, whose study achievement includes reinforced-asphalt seismic isolation layer and reinforced-asphalt seismic level isolation pier. The experimental results show that the proposed technology shares excellent seismic isolation performance, and provides low-cost expenditure and simple construction method, which is most suitable to vast rural areas’ building in China, and it can also be implemented to the third world countries. The reinforced-asphalt isolation layer technology has been applied to engineering practice, which is the first building adapting the new technology. Meanwhile, experimental testing is carried out on it, which suggests a superior damping effect. The proposed level isolation pier technology simplifies utilization of civil buildings in rural areas.

In order to investigate the failure mechanism,failure mode and hysteresis curves of the low strength row-lock cavity walls strengthened with HPFL(High Performance Ferrocement Laminate), eight pieces of rowlock cavity walls subjected to low-frequency cyclic loads and a constant-amplitude vertical load on top were tested, and the results showed that the bearing capacity, ductility and energy intensity all were greatly improved on the basis of comparison and analysis of the seismic behavior influenced by different strengthening methods. In addition, this article proposed the calculation formulas for reinforcement design reference .

Combined with the respective advantages in S-R(Sway-Rocking) impedance concept and finite-element method, a simplified 3D structural dynamic FEM considering composite pile-group-soil effects is presented. The structural members including piles are modeled by spacial beam or shell elements, and raft-base is divided into thick-shell elements with its spring-dashpot boundary coefficient obtained by impedance backcalculated. The mass-spring elements for soil between piles are set to simulate vertical, horizontal pile-group effects by strata-equivalent approach. The soil beside composite body is separated into near-field and far-field parts. The former is modeled by nonlinear spring-dashpot elements based on Winkler’s hypothesis, while the latter is modeled by a series of linear mass-spring-dashpots. With the effects of boundary track forces and energy radiation, the presented model enables researchers to conduct the time-domain nonlinear analysis in a relatively simple manner which avoids sophisticated boundary method and solid-element mesh bringing with tremendous computational cost. The seismic effect on dynamic interaction of pile-soil-complicated structures would be efficiently annotated from two structural engineering and geotechnical engineering aspects and the numerical calculation effort would be drastically decreased too. The complete procedure is mainly performed using the parametric design language assembled in the Finite Element Code Ansys. With the dynamic analysis of foundation and superstructure for a pile-supported 15-storey building, the influence of the participant effect on structural dynamic response will be depicted by various dynamic parameters of pile-soil-raft foundation in detail. Not only do the results have an agreement with some conclusions drawn by the general interaction theory, but also certain of phenomena which would be disagree with that by general analysis is involved. Even with the finite-element meshes for 68 piles, the time-history analysis procedure for PGSS (Pile-Group-Soil-Superstructure) system and the qualitative evaluation with various SSI parameters can be also fulfilled efficiently and rapidly by presented means. These results may be of help to the designers to quickly assess the significance of interaction effect for the high-rise buildings resting on any type or layout of pile-group foundation.