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The seismic behavior of a slope site has a critical impact on its stability and the seismic response of structures located on or near the slope. In this paper, a hybrid boundary method(HBM) is proposed for the site response analysis of slopes. Viscous and viscous-spring boundaries are applied in the HBM and equivalent loads are calculated separately on the bottom and the lateral boundary. A horizontally extended model is used to verify the HBM. The results show that the maximum error of the HBM is only 2.010%. On the ground surface of the slope site, amplification occurs at the crest side and de-amplification occurs at the toe side under various cases. The ratio of the maximum and minimum PGA on the ground surface could exceed 2. Therefore, great attention should be paid to the spatial variability of ground motion on slope sites. The HBM is also compared with four conventional approaches. The maximum errors of all the conventional approaches exceed 70%. These examples demonstrate that the HBM has much higher accuracy in practice than conventional approaches.

Ram-compaction gravel pile with end expansion is widely adopted in the treatment of silty clay foundations. In this paper, the bearing properties of rammed gravel pile reinforced foundations and soil between piles were investigated by use of static load tests and heavy-duty dynamic penetration test. It is demonstrated that the settlement curves (P-S curve) of ram-compaction gravel pile with end expansion reinforced foundation and soil between piles were monotonic, without turning point being observed. With the increases of pile length, the bearing capacity of pile increases. According to the experimental results from heavy dynamic penetration tests and static load test, the strength of soil between piles is improved, which also have effects on the elimination of the uneven settlements. Comparison the results between heavy-duty dynamic penetration tests and over-heavy dynamic penetration tests shows that the later one is suitable on testing of the soil properties between piles. In addition, from in-situ measurements of uplift deformation of different depths, it is found that uplift behavior occurs with depth more than 0.5m, whit largest uplift value of 21cm. The result provides a reference for the design and construction of rammed gravel pile reinforced foundation.

Using coupling model, the time-effect behavior for deep pit during excavating and dewatering is studied. The distribution of the seepage field, the horizontal displacement of wall, the settlement of surrounding soil and the settlement of the road are all obtained from the coupling analysis. Taking the deep foundation pit engineering of one station as engineering background, the coupling of seepage and consolidation is simulated in the process of excavating. According to the comparative analysis between the simulation value and the measured results, it can be known that the calculation value considering the coupling of seepage and consolidation is well in accordance with the measured value. The analysis shows that the provide method can be used to simulate the deep foundation under the coupling effect and it is reasonable, feasible, and can provide some kind of references to design and construction.

In this paper the propagation of axially symmetric compression wave in an infinite transversely isotropic magnetoelectroelastic cylinder is presented. Following Pan(2002), the general boundary conditions on the surface of the magnetoelectroelastic cylinder are written by a simple vector equation that is similar to the purely elastic counterpart. By assuming the possible form of the solution, the generalized Pochhammer frequency equations are presented and the corresponding phase velocity curves in some range are given. Numerical examples are also presented to show phase velocity curves under the first 4 kinds of boundary conditions. Other boundary conditions can be studied under farther research.

Researches of wave motion are important on theory and application. The forward problem and the backward problem are the two aspects that relate with each other. In this paper, with the combination of FEM considering BGT absorbing boundary condition for forward problem and GA method, the inversion of target’s characters in infinite area is discussed. The absorbing boundary condition is obtained through approximating the Sommerfeld radiation condition. Although the absorbing boundary condition can’t simulate the effect exactly, it can reach the limitation in the practice and has the character of solving the coupling that simplifies the calculations. Because of the use of finite element model method, the forward problems that involve special geometrical shaped scatter and multi scatters can be solved. The finite element model is used iteratively to compute the scattered field. In the inversion process, the GA method is adopted because of its advantage of global optimum search and parallel calculation. The numerical simulation examples of single and multiple show the validity of this method.

The stability and smoothness of embankment is very important factors for the design of a new high-speed railway project. To make an accuracy prediction of the post-construction settlement, it is necessary to carry out a carefully settlement observation during the construction of embankment. The defects of traditional settlement plate, however, are well known as disturbing construction and destroyed easily by construction. In this paper, based on the application in Shi-Wu passenger dedicated line, a new type of settlement plate has been developed. The application of this new type of settlement plate in site shows that it has no any disturbs on the pavement and compaction of embankment. And measurement becomes simple and easy to operation. Accordingly, high accuracy of settlement observation can be obtained by this method, which has the value of application in high-speed railway settlement observation.