The mathematical foundation and corresponding physical sense in large numbers of constitutive models of geotechnical material are important to understand and use them. The mathematical foundation and condition of all kinds of geotechnical constitutive models are pointed out。The keystone is whether or not there is unique potential field in which the stresses（strains）or their increments are its gradient vectors. The mathematical conditions include coaxiality of principal stresses and strains and their increments; symmetry of modulus matrix; rank of the matrix equal to 1; the curl of gradient vector equal to 0. The generalized potential theory is proposed in which unique potential function or 2-3 potential functions with linearly independent gradient vectors are used to determine the stress-strain relationship. The theory is provided large capacity and with wider application field for geotechnical material with complex mechanical properties.

A new mathematical soil model is developed for the one dimensional consolidation process. This model is used to explain the effects of secondary consolidation before the consolidation and to calculate the compression time curves. The results of analysis by new method give a reasonable engineering assessment of published experimental data.The purpose of the consolidation tests was to invesigate the influence of the maximum length of the drainage path and the time interval of the loading step on the rate of consolidation and the magnitude of compression for a remoulded normally consolidated clay exhibiting large secondary consolidation. The test results have been compared with the prediction for the consolidation process by the proposed method.

Base on the norm analysis of seismic signals and the structural system, the mixed optimal control index J is cited; and its physical implication is defined. The influence of soil-structure interaction(SSI) is considered. Considering the merits and defects of the H2 and control scheme, the controller is worked out by LMI convex optimal solution; the mixed control schemes that minimize the index J on condition that is given a definite value, are proposed.

In practice, pile-soil-cushion interaction of composite grounds with piles is not well considered in bearing capacity and settlement estimation. To solve it, based on the relation among pile-soil-cushion, the differential equations of settlements of piles and soil in large-area pile groups together with their solutions are presented. Compared to the results of finite element analysis, these solutions are quite accurate. This method greatly enhances the speed of calculation. The parameters used in this method are all routine soil parameters and are easily obtained through soil test. Also, the stress dependency of both the soil-pile limit friction and the compression modulus is taken into account in the proposed method. This method is practical and applicable to calculate pile-soil stress ratio and settlement of composite grounds with piles.

In order to probe into seepage characteristics of rocks during their whole deformetion processes,the authors have carried out seepage tests on the specimens of granite which were taken from the high slope at the permanent shiptock of the Tree Gorges Project, and specimens of limestone which were taken from the high slope at the Wanjazhai Hydropower Station in Shanxi Province, under several surrounding pressures.The test results show that the rocks have obviously unlike seepage characteristics before and after destruction of rocks; and the permeability behavior of the rock during deformation has an osculatory correlation with the style of deformation destruction. On the basis of tests, the mechanism of seepage characteristics of complete stress-strain process is discussed further so as to offer the valuable support for the problem of coupling stress field and seepage field of jointed rocks in hydropower projects.

The centrifuge model tests were performed to investigate the ground settlements during tunnel excavation in sandy soil ground. A columnar rubber membrane tube was used to represent a tunnel. Compressed air was supplied to it to create a uniform pressure to support the surrounding soil. During centrifuge running, air pressure was gradually decreased to simulate the initial stress release; i.e., to simulate the excavating process. Through different combinations of test conditions including soil type, density, water content and tunnel embedment depth; the ground failure patterns and settlements were examined; the normalized P-S relationship were obtained and discussed..

The seepage pressure effects are comprehensive actions on cover-layer in the process of rain feeding karst groundwater, which includes load-increased effect of water, vertical-seepage effect, wetting-soft effect and obturation negative-pressure effect. And the seepage pressure mechanism is the primary mechanism of karst collapse in the center of cone of depression in continual pumping region. Based on the theory of М•М•Протодьяконов , the limit equilibrium theory and the karst collapse law in Zaozhuang city, this paper has established the mechanical model of surface-collapse phase and determined the height of equilibrium soil-hole in inter-collapse phase. Meanwhile, an evaluation of karst collapses in Zaozhuang city has been carried out by means of the formula and mechanical model. The result shows that the formula and mechanical model coincide with the forming mechanism of karst collapse in Zaozhuang city.

Parameter evaluation is one of key problems in numeric analysis considering non-homogeneous rockmass and complex surroundings as well as dynamic mechanic features of slope rockmass. Its accuracy has direct influence on accuracy and credibility of computational result. On the basis of parameter back analysis, excavation effect of permanent shiplock high slope of Three Gorges Project and further stress-strain state are analyzed. It provides foundation for deformation and stability analysis of operation stage of permanent ship lock.

It is the first time that using the newest specified loading equipment corresponding to the CT machine, the real-time computerized tomography testing of meso-damage propagation law of jointed rock sample with single crack under unloading confining pressure has been accomplished in rock mechanics fileld. Through CT scanning, the clear CT images are obtained to include the whole process of rock failure on unloading confining pressure from the crack development, penetration and fracture failure in the different stress states. It is clear that it is easy for failure phenomenon to happen suddenly in the process of unloading condition of jointed rock

According to the test data about flyash on chemical analysis ,grading test, compaction test, triaxial shearing test and compression test, the engineering traits of flyash ,such as compression trait and strength trait are studied. The factors influencing on engineering traits of flyash and its application as replace material in ground treatment, are also discussed.

A new rheology mechanism in according with the function of cohesion during the course of rheology for rock is expounded; a new 1-D constitutive model for viscoelastoplastic rock is set up, and the corresponding 1-D creep model and the corresponding 1-D laxity model are deduced. The creep model is used to simulate the curve of rock’s creep in the experiment. The model is verified by the experiment.

Using the special purpose loading equipment made by authors corresponding to CT machine ,the computerized tomography (CT) real-time testing of specimen’s failure with single fracture and hydraulic pressure under uniaxial compression has been made. The whole procession of specimen being compressed, new damage coming up and the failure process of hydraulic fracture of rock are simulated .At different axial pressure ,clear CT images and CT values of different parts are obtained .With studying the data of test , the threshold value of damage and damage propagation rate are defined; and some discussion of hydraulic pressure’s effect is made. The damage and fracture propagation law of jointed rock has been obtained from meso-scale and three dimensions.

A numerical iteration method for determining load-settlement relationship of a single pile is developed considering the pile-soil(or rock) interaction. The P-S curve of such a pile is obtained and can be used for calculating the load bearing capacity of the pile.Comparison between the results obtained by the proposed method and the measured data is made; and close agreement has been found. It is shown that the proposed method is theoretically reliable, simple in application and useful in practice.

On the basis of analyzing the coupling method of analytical solution for drainage hole and FEM[6,7], the improved analytical solution for drainage hole was proposed for six-side element and then coupled with FEM. An example of seepage with a drainage hole was calculated by the old and new methods respectively . By comparing the results, the improved method is illustrated to be more reasonable.

A series of stress path tests are carried out for undisturbed mucky clay samples from Hankou. The tests results indicate that there is a good hyperbolic connection between the axial strain and stress ratio R in those decreasing p path tests, then a normalized hyperbolic model of stress-strain is proposed for soils which undergo decreasing p path. Volume change behavior in drained tests and pore pressure characteristics in undrained tests are also described.

The geotechnical problems of municipal solid waste(MSW) landfill are discussed. At first, the compendium of MSW landfill in China is described. Secondly, the present situation of research in this domain, including geotechnical properties of MSW landfill materials，landfill lining system and landfill slope stability are discussed emphatically. Finally, the research prospects of the geotechnical problems of MSW landfill in China are also briefed.

Through introducing researches about mechanism of ground anchorage transferring load and reinforcement effect in detail, the research status quo of anchorage theory of rock and soil is discussed emphatically. Finally, the existing questions, and developing direction in study are pointed out too.

Based on the load-structure theory and using the object-oriented programming method, the theoretic basis of CAD software (GeoFBA) for shield tunnel lining is described and its usage and feature are also expounded. The software provides the various possible linear and nonlinear models as well as verification for segment design specification, and is suitable for two segment assembling types with the straight joint and the staggered joint. The software has been used widely in practice, which is a powerful tool to designers and researchers, and enhances greatly the productivity of designers.

Stratum is an important idea of three dimension strata model. It plays a key action in instauration of three dimension strata model. How to describe strata based on lithology is very important. In this paper, according to the range of rock formation interface in geological drill hole sampling, the ordering of strata is ascertained. In the light of multi-DEM set-up model idea, pursuant to lithology, the intersection division for multi-DEM proceeded. Three dimension strata model was formed in terms of lithology.

The 3-D FEM is used to calculate stability of the CB20B bucket foundation platform made by Drilling Technology Research Institute, Shengli Petroleum Administration Bureau. The stability of the platform is related to the whole construction of the platform, also to the mechanical propeties of oceanic soil in the foundation and to the act each other between the platform and the soil under wind, waves, ice and ocean current loading. The results of calculation show that CB20B platform is rather stability under the conditions of design.

The slope in Jiangjiagou Valley suffered from serious erosion due to the substance components, climate and the complicated erosion power. This paper expatiates the serious erosion on slope surface from the substance components, climate and rainfall.It also analyses the erosion principle and process with experiment of erosion inspired by artificial rainfall.The results of the experiments indicate that the runoff increases hopingly and fluctuatingly along with rainfall, while sediment content decreases when the rainfall increases.

The three-dimensional limit method for slope stability analysis includes the upper bound method and the 3D limit equilibrium method. The upper bound method features in its rigorous theoretical background and simple numerical procedures. The 3D limit equilibrium method is actually an extension of the Spencer Method in 2D area. It provides a more rigorous theoretical background, compared to those already published in the literature. To combine the upper bound method with the 3D limit equilibrium method, the 3D factors of safety can be reasonably bracketed in a small range. Its applications to Xiaowan deposit project show its feasibility and practicality.

Plastic wick drain and preloading method is adopted to consolidate the soft ground. The construction procedure is reasonably planned; and the systems of drainage and monitor are reasonably arranged. Through analyzing the results of monitoring and checking data , it is shown that the effect of consolidation of soft ground is excellent; and the design standard is reached.

The back analysis of displacements for Fenggong Tunnel of the East River-Shenzhen Water Supply Reconstructing Project is carried out. A new method of using the soften yielded elements in the finite element method simulating the fractured and flexible range by the excavation is discussed. The analysis results of the tunnel by this new mothod are consistent with the measured values.

The monitoring design has been discussed in detail about soft soil embankment ( segment K54+350～K54+560 , Guang -Zhao expressway ) which is treated by jointed vacuum-preloading method . The rich inspection results have been obtained. Through analyzing the obtained data, it is shown that the jointed vacuum-preloading treatment method is successful; and it can be adopted in the similar engineering cases.

Grouting method was used for shoring and preventing seepage in blasted cavity soils,in order to solve the blasted cavity soils question of stability of stability and seepage rate and collapse.Comparison tests of the gravity grouting method,pressure grouting method, the pressure grouting method method with the waterproofing agent and without any support were done by using the critical water-cement ratio of 0.8:1.It is proved that the gravity grouting method can not meet the need;the pressure grouting method is feasible for shoring and preventing seepage in blasted cavity soils;and it is better with the watrproofing agent added.

Based on the existent status of pore water pressure,by using the effective stress principle of unsaturated soil,the extension of elasticplastsion of elastoplastio model of saturated soil to unsaturated soil is carried out;a modified Cam model which can account for unsaturated soil's gradually collapsibility is established.The model has few parameters and cam get them from water characteristic curve and saturated soil's test; it is applicable in practice.

A method was presented for reasonably evaluating of bolts reinforcement of the shear strength of rock joints.The effective approaches to improve the bolts reinforcement efficiency are discussed by analyzing several important factors which have influences on the bolt reinfrocement efficiency.Therefore the defects of relevant analysis proposed before by many anthors have been inproved.

On the basis of the transferring matrix method,which is an explicit solution for acisymmetrice problem in layered elastic half space,the calculation method given in this paper can reduce the error,which is caused mainly by the integral variable ξ The terms can be divided into two kinds.One includes 1/ξ and the other does not.For different cases,different transferring matrixes;should be chosen the modificatory transferring matrix and the preliminary transferring matrix according to whether the term contains 1/ξ or not.

Artificial ground freezing techningue will be used extensively in the underground construction,with ever increasing attention paid at home and abroad.Each method of frozen wall thickness was analyzed.The vavious methods for determining thinckness of a frozen soil wall are described and analyzed.Meanwhile,the tranin of thoughe and concrete contenets of desingning frozen soil walls'stability and reliabllity are also expounded.Finally,its research direction in future is proposed.