Applied Mechanics and Materials Vols. 405-408

Abstract: Based on the analysis of the causes and characters of common security risks in nuclear power stations breakwater, using the ground penetrating radar (GPR) to detect breakwater, and to explore the applicability and accuracy. The analysis showed that ground penetrating radar as a non-destructive detection method for the detection of the breakwater is feasible, and the detection accuracy meet the actual requirements of the project, the results can be used for the safety detection and maintenance of the breakwater.

Abstract: Abstract: The stress and deformation of rock-fill dam with asphalt concrete core wall founded on deep overburden is calculated and analyzed by Duncan E-ν model and double-yield-surface model through three-dimensional finite element method. The stress and deformation of dams in water storage period is compared by the two models, the results show that the deformation distribution of dam core via two different models are coincide one another. The horizontal displacement and vertical displacement of rock-fill dam with asphalt concrete core wall by double-yield-surface model is smaller than which by Duncan E-ν model in the period of water storage. Furthermore, the horizontal displacement and vertical displacement by double-yield-surface model, which are close to the practical test data through the deformation via two models are in good agreement. The analysis of core-wall stress via double-yield-surface model is more reasonable than the Duncan E-ν model. The analysis result of resisting hydraulic fracturing of core dams by DuncanE-ν model is coincide which of core dams by double-yield-surface model.

Abstract: This paper introduces the research status of bearing capacity of ashes foundation,presents the purpose of bearing capacity ashes foundation,and shows the research content and may encounter difficulties. The study on bearing capacity of ashes foundation will change the history that the ashes can't be directly used as the foundation, which finds the cheaper the foundation material for some area, and saves a lot of money. The study also can solve the problems of housing which has been built to provide references for the study of civil engineers.

Abstract: The aim of this research is to better understand the behavior of reinforced structures of two sides vertical anchored block backfill reinforced retaining wall. A vertical model retaining wall, 3m high and 5m long, which was constructed by reinforced backfill using two sides vertical anchored blocks. The results showed that the maximum lateral wall displacements increased almost in the middle of the wall height with a maximum value above the wall base. The measured earth pressures showed that the horizontal earth pressures exerted on the wall facing are greater than those inferred from the Rankine active state up the 1/3H of the wall and are lesser than those inferred from the Rankine active state under the1/3h of the wall. The measured and the calculated displacements of wall show very encouraging agreement although the deformation was slightly over predicted at the top and bottom of the wall.

Abstract: Combined with the project cases, introducing the principle the method and controlling process of stress relief, indicating the feasibility in the application in the soft soil area.

Abstract: The purpose of the present work is to investigate the dynamic interaction between plate and structure in a poroelastic half-space produced by moving load using a semi-analytical method. Biots dynamic equations are solved by the Fourier transform technique. The forces and displacements of the superstructure, plate and poroelastic medium at any time are obtained by using the numerical inverse transform technique. Based on the derivation and numerical examples presented above, the following conclusions are drawn: the horizontal displacements and vertical displacements of each floor of the superstructure increase with increasing the velocities of moving load. The vertical displacements in each floor have small change.

Abstract: Arching effect exists in narrow backfilled stopes. In this paper, numerical software-FLAC was used to research the vertical stresses distribution in vertical backfilled stopes, and to study the effects of parameters on stresses distribution. Backfilled stopes can be designed reasonably by the modified parameters.

Abstract: The dynamic parameters of the permafrost are very important for engineering design, also using in the numerical calculation. The dynamic parameters directly affect the correctness of engineering design and numerical simulation. Beijing Jiaotong University developed a novel dynamic load direct shear apparatus to measure these parameters. In the paper, it is analyzed Power systems, measurement and control systems of the dynamic load direct shear apparatus, and gave a verification experiment, the results show that dynamic load direct shear apparatus can complete its purpose.

Abstract: The reservoir bank instability is the outcome combined the action of the external factors with the action of the internal factors. The limit equilibrium analysis, the strength reduction finite element method, the saturated/unsaturated seepage coupling and so on were applied to analyze the reservoir bank stability. The condition analogy graphical solution methods, the mathematical analysis method, the balanced cross-section method and so on were applied to forecast the reservoir bank stability. The reservoir bank instability mechanism depends on the physical action, the chemical action and the mechanical action of the water in the reservoir bank rock and soil. At present, the drainage measure, the cutting slope and reducing load measure, the retaining and supporting measure , the anti-slide piles measure and so on have been widely used to control the reservoir banks instability. Aiming at the research status of the reservoir bank instability, the problems in study and the suggestions for future work are pointed out in this paper.

Abstract: A kind of depth-measurable prefabricated vertical drains (PVD) was applied for soft ground improvement in Tianjin, China. Test was conducted to check the effectiveness of impulse method for detection of installation depth of PVD. The PVD were set into two groups in length: 20 m and 8 m. The installation depth of PVD was checked in 24 hours since they were installed. The tests result revealed that the measuring precision of impulse method is fairly good but it can be effect by the installation depth. The measuring precision can be controlled in 2% for most PVD when the installation depth was about 20 m. There is a fall down of precision when the installation depth was about 8 m. There is no need for additional construction measures when the PVD for impulse method are installed. All of the PVD installed can be checked for installation depth easily, so the apparatus and measuring method are good in operability and stability.