Papers by Author: Yong Mou Zhang

Abstract: The static load test of composite foundation was simulated by using the nonlinear finite element programs, and the changes of the pile-soil stress ratio and the pile and soil settlements as well as the plastic deformation of composite foundation were analyzed. The simulation results show that: the cushion of flexible pile composite foundation can effectively regulate the pile-soil stress ratio and make the bearing capacity of the lime soil pile and the soil between piles give full play at the same time. The cushion has a distinct role in reducing the pile settlements, however, has little effect in reducing the soil settlements. The reasonable cushion thickness is about 300mm. The composite foundation will emerge local shear failure when it reaches the ultimate bearing capacity. Reducing the pile spacing can increase the ultimate bearing capacity, and the rate of increase shows a gradually increasing trend.

Abstract: The seismic responses of solid pile and hollow pile were analyzed and compared in this paper. According to the deflection equation of pile during earthquake, rotation, bending moment, shear force and soil resistance of pile were obtained. The differences of deflection, rotation, bending moment, shear force and soil resistance between hollow pile and solid pile, whose effective areas of cross-sections were same, were found. From calculation results, hollow pile had certain advantages in seismic performance. This study provided a theoretical basis for the applications of hollow piles in practical engineering.

Abstract: According to the monitoring results of soft clay treated by preloading with plastic drainage pipe, the consolidation settlement effect of soft clay with 50kPa preloading load, 21m plastic pipe, 1.2m and 1.5m distance was compared with that of 30kPa preloading load, 6m plastic pipe, 1.5m and 2.0m distance. The analysis showed that, the preloading method with deep plastic drainage pipe can accelerate the dissipation of excess pore water pressure in deep soft soil. The over-flow penetration may occur in the confined water. The elastic deformation appears and recoveries after unloading. This is not conducive to the consolidation of soft clay layer 4. The plastic drainage pipe whose depth and distance should be 18~20m and 1.5m respectively to the consolidation soft soil in Pudong.

Abstract: The numerical model for opposite-side simple-support-free rectangular plate is established based on the theory of engineering vibration. The basic differential equation of transverse vibration of thin plate and the method of development of trigonometric function series are being used to analyze the behaviors of rectangular plate under moving area-loads in constant speed. The analytical solution of dynamic response for plate was obtained. This model can be used to simulate the dynamic response for thin plate under moving shock load and to assess the yield state of thin plate under shock loads. The Mises' yield criteria was used to judge the dynamic yield case of plate under shock loads. The distribution of stress and strain of dynamic response in parent plate under shock loads was solved according to the free-simple harmonic oscillation equation of plate. The calculation results can be used to analyze the plastic area and visco -plastic area of stress distribution in the plate. It is of some guiding significance for the installation structure of parent plate in explosive welding.

Abstract: In this paper, In order to reasonably determine the mining width and reserves length of strip mining, reliable simulation subsidence due to strip mining under earth，according to the cavity environment of the engineering measure, the protected object's space position and the mining rock strata's circumstance, and the relevant mining subsidence mechanic, calculation model are chosen in order to predicting the designing mining area transform and data sorting after mining. Its function and perform is put into practice for all various aspects of subsidence calculation in visual analysis system of own developed software package. It is applicable to all mining geological conditions and mining methods. Based on the condition of strip and pillar practice of Matigou colliery of Huating Mining Group, It is also applicable to this calculation system to guide successfully mining under river and architectural complex, the accurate estimate forecast had been attained.

Abstract: The consolidation coefficient, permeability coefficient and other parameters were calculated out based on field measurement data of pore water pressure in this paper. The post-construction settlement behaviour of dynamically consolidated foundation was also simulated. The simulation results were consistent with the actual observation results. The method of this paper provides an effective way for the prediction of post-construction settlement of dynamically consolidated foundation.

Abstract: Ground subsidence is one of the main geological hazards in Shanghai. The ground subsidence is caused by pumping groundwater greatly. In the past, studies of ground subsidence in Shanghai were mostly taken for the ground subsidence caused by pumping confined water in Puxi. And ground subsidence caused by pumping phreatic water was rarely studied. Dewatering preloading is a new technology for soft soil treatment. The monitoring of ground water level, ground subsidence, pore water pressure in the process of dewatering preloading test for a soft soil treatment project in Pudong showed that pumping phreatic water can also cause ground subsidence. The ground subsidence caused by pumping phreatic water was analyzed in this paper. The relationship between phreatic water level and ground subsidence was obtained.

Abstract: Consolidation coefficient and percent consolidation of soft clay were calculated according to the measured pore water pressure of a project in Pudong Shanghai. Calculated coefficient of consolidation was one magnitude larger than the experimental one. This was in conformity with the actual consolidation process of dynamically-consolidated soft soil.