In order to find a thorough stress-strain characteristic in clay, a series of consolidation undrained plane strain compression experiments were made. Local lateral non-homogeneous deformation in the samples were recorded. Through analysis for the experimental results, it is found that characteristic values of localized deformation began to form are very close to suddenly increased turning point of the pore water pressure. But the suddenly increased turning point of the pore water pressure is its yield point in clay soil. It is shown that the deviator stress of shear band began to form is very close to its yield point in clay soil. Exceeding this point, the localized deformation speeds up. The discovery will conduce to a thorough study on strength theory, deformation and stability analysis in soil.

The concept of “average soil skeleton stress” is introduced. The stiffness parameters of unsaturated soils, , , and , have been derived. The LC yield function, hardening rule and the ellipse yield function of triaxial stress state have been also studied. Based on the physical processes and mechanism of the soil mechanics, the change relationship between the degree of saturation and the volume strain of the soil has been presented by the net mean stress and suction action. The advantage of the constitutive model of unsaturated soils is that it can take into account the important parameters of the degree of saturation in different stress states. The verification results of the partial test data show that the constitutive model is available.

Critical slip surface search is one of key problems in slope stability analysis. Present search methods include mathematic programming methods and brainpower search methods, which are based on the assumption of arc or arc-polyline slide style, and developed on basis of soil slope. It is not fit for rock slope. Critical slip field theory is based on residual thrust method and optimization theory. Useing new structure surface processing method, it can calculate the biggest residual thrust field, which is almost consistent with actual condition and easily search slip surface of respectively possible exits. Therefore, it can find the whole slope critical slip surface. First of all, using example of homogeneous material slope validates credibility of calculation result to be consistent with the result of shear strength reduction technique and the Spencer's precedure of limit equilibrium. Then, an example of open strip mine side slope is given to validate the practicability of this method.

Elastoplastic models can’t simulate strain localization due to ductile damage evolution. A porous geomaterial is modeled as an aggregate of spherical thick-walled shells, so the damage of a representative volume element can be characterized by a scalar variable, i.e. the void volume fraction, and a coupled plastic damage model for geomaterials based on micromechanics was proposed. This model was implemented into the commercial FEM software MARC through a user subroutine, and strain localization of geomaterials was studied. Shear band formation due to void nucleation and growth were successfully simulated in a specimen of geomaterial under plane stress compression and tension by the model respectively. Shear band formation in an arch dam under overloading was studied also. It is shown that the strain localization appeared first at the heel of the arch dam.

Starting with the first and second laws of thermodynamics, the free energy function and dissipation potential function are discussed; then the corresponding yield loci, flow rules as well as hardening rules are deduced in a systematic manner. Within the framework of critical state soil mechanics, a new method that combines the anisotropic model based on thermodynamics and specific rotation hardening rule is presented for dense sand. Then triaxial drained and undrained test curves are simulated with given model parameters; and the influence of model parameters on curve shape is discussed briefly. The results prove the validity of this method, which covers the perplexing triaxial test curve in dense sand by adopting variational rotation directions, as well as guarantees the consistence of dilatancy function with yield locus because of the thermodynamics basis involved. The models constructed through this method have the advantages of the strict structure, the extensive applicability and the simpleness.

The engineering characteristics of composite foundation with rigid-flexible and long-short piles are studied. By using the finite element method, the effects of cushion modulus, cushion thickness, short pile modulus, and long pile length on the total settlement of composite foundation, the stress ratio of long-short pile, and the axial stress of long-short pile are discussed respectively. The results show that the engineering characteristics of composite foundation can become more reasonable by optimizing material parameters; and long pile can effectively reduce settlement of composite foundation. Based on the in-situ measurement of pressures in soil and piles of a practical engineering in Wenzhou City, stress ratio of pile to soil and pressures in the process of construction are analyzed. Some conclusions are provided as references for future design and application of this kind of composite foundation.

According to the basic equation of dynamics, using FEM and NEWMARK implicit integration algorithm, an elastoplastic numerical analysis is made to analyze the efficiency of vibration isolating groove to the vibration caused by vehicle load. In order to reduce the effect of wave reflecting on border, finite element and semi-infinite element are respectively used to discrete the internal and border parts. The position of the vibration isolating groove and its depth and width are the three mainly considered factors. Finally, on the basis of the numerical calculation results, their effect laws are analyzed.

On the basis of the YAI(yield approach index) concept and its phase complementary parameter ω called danger coefficient, which were proposed in the previous paper by the authors, the new concept, FAI, is introduced. It is the sum of danger coefficient ω and FD(failure degree) which describes the damage degree of rockmass in the plastic zone. Two cases are presented to analyze the validity and utility of FAI. The results proved that this parameter can line out the position and extent of failure zones, damage zones and disturbed zones, and characterize the stability rules of rockmass. In the stability assessment of slope engineering, the sliding surface denoted by this parameter perfectly agrees with that measured in situ. So, FAI is of very importance in the stability assessment, the election of excavating and supporting schemes.

Shear rheology experiments were carried out for the shale in Longtan Hydropower Project by using a servo-controlled shear rheology testing machine. The variation law of shear displacement of shale with the time is analyzed. The variation tendency of shear rheological rates under different stress states is discussed. At the same time, the variation of shear strength of rock with the time is discussed. When the proposed nonlinear rheological component (NRC model) by the author is parallel connected with Kormanura model; so that a new nonlinear rheological model can be gained, which can describe the accelerating rheological properties. Using the shear rheological curves of shale, the proposed nonlinear viscoelastoplastic shear rheological model of rock is identified, which gets the viscoelastoplastic rheological parameters of the shale. The comparison between the rhelogical model and experimental result shows that the proposed rheological model behaves reasonably well.

The geosynthetic reinforcement layer techniques have been widely used nowadays in the foundations and embankments. During the course of the design of the geosynthetic reinforcement layer, the confirmation of the stress diffusion angle is very important, but no good methods to calculate the stress diffusion angle. This paper presents the method of calculating the stress diffusion angle of geosynthetic reinforcement layer based on additional stress back-analysis; and then using this method, researching the setup parameters of geosynthetic reinforcement layer ( the thickness of geosynthetic reinforcement layer, the composite modulus of compressibility of geosynthetic reinforcement layer) and geosynthetic factors (such as reinforcing space, reinforcing width, total numbers of geosynthetic reinforcement layer etc.)on the distribution rule of the stress diffusion angle; the results indicate that the range of the stress diffusion angle is 45-60 º; further more the setup parameters of geosynthetic reinforcement layer and geosynthetic factors existing optimum values, corresponding on these values, the stress diffusion angle reaches the max. Finally, using orthogonal tests and regression methods, many effect factors on the stress diffusion angle are analyzed, the results indicate reinforcing space has a most effect on the stress diffusion angle of the geosynthetic reinforcement layer, secondly the embedded depth of the first geosynthetic, however, reinforcing width has a slight effect on the stress diffusion angle.

Based on the Nanjing metro shield tunnel traversing sandy strata, systematic in-situ investigation and theoretical simulation of the beam-spring model with consideration of the interactions between lining structure and surrounding soil during the segment assembly and stabilization are carried out. Influences of the shield tail serum injection, soil stress relaxation, water pressure and segment ring assembly on the distributions and varying laws of sandy strata segment ring soil pressure, the longitudinal joint gap and internal forces are discussed. The characteristics of the interactions between shield tunnel segment and the sandy strata are investigated. The applicable principle and method for metro shield tunnel segment design in sandy strata are also proposed.

Thanks to the creep behavior of salt rock, drilling hole in the salt deposit of deep stratum is a very important and difficult problem in petroleum engineering. The creep of salt deposit often causes oil borehole losing stability, blocking aiguille and demolishing oil well casing, and brings huge economic loss. Based on the measured result of the drilling hole diameter between the different time in Shengke 1 borehole drilling engineering, the creep velocities of the rock layer in the deep stratum are obtained. The exponent creep constitutive law is employed to analyze the creep velocity of rock layer in the three dimension numerical method. The creep parameters of salt rock and soft mudstone are obtained. The creep velocities of rock layer under different drilling mud densities and salt layer depth are also analyzed based on the obtained creep parameters. Considering the permissive stratum creep velocity during drilling, the optimum drilling mud densities under different salt layer depths are obtained. The research result can be used in drilling engineering.

By the FEM numerical method, the characteristics of loading and deformation in widened highway subgrades with retaining wall in mountainous areas are discussed. The results by FEM show that in the subgrade-widening project in mountainous area, settlement curve of the subgrade features the shape of scoop; in contrast with the one in the shape of parabola in new-built highway; not only the treatment of jointed section between new and old highway subgrades, which is the key task in normal widened highway subgrade, but also the treatment of jointed section between new highway subgrade and retaining wall should be stressed in the subgrade-widening project in mountainous area; the lateral earth pressure distribution of retaining wall exhibits nearly a parabolic curve, different from the triangle form by classical earth pressure distribution theory. The analyses on the effects of the widened extent, the slope of old embankments and the different characteristics between the old and new materials of subgrades, reveal the rule of uncoordinated deformation between the new and old subgrades, and the characteristics of the lateral earth pressure distribution of retaining wall.

In order to investigate the law of failure and deformation of statically loaded rock under periodic load, by using the Instron electro-hydraulic and servo-controlled material testing machine, uniaxial test of red sandstone subjected to static-dynamic coupling loading is carried out. Furthermore, by way of combining uniaxial horizontal static loading device made by self and Instron electro-hydraulic and servo-controlled material testing machine, biaxial test of red sandstone subjected to static-dynamic coupling loading is performed. Experiment indicates that the failure mode of statically loaded red sandstone under periodic dynamic load changes according to different static stress states. The hysteresis loop of stress-strain curves of statically loaded red sandstone under period dynamic load is first sparse, and then dense, and then sparse, afterwards rock failure appears. Although the number of hysteresis loop and the value of complete strain of stress-strain curves of the same statically loaded red sandstone under different periodic dynamic loads are different, deformation of statically loaded red sandstone under period dynamic load obeys to the law of ultimate deformation of rock under period load; and there is tendency to the same equivalent complete strain energy of rock failure.

The exact analytical solutions for displacements and stress of a double layers generalized Gibson elastic subgrade subjected to an axisymmetric surface load are presented. It is assumed that the soil of the subgrade is incompressible and that the shear modulus varies linearly with depth. In the two layers, the ratios of coefficient of linear term to constant term of the shear modulus expression are also assumed to equal during analyzing. Selected numerical results for vertical displacements are presented to portray the influence of the degree of nonhomogeneity, depth of second layer and different stiffnesses of the two layers on the responses of the nonhomogeneous subgrade. Hankel transforms are used in the analysis.

Shaped steel reinforced cemented soil retaining wall can be used when the depth of excavation is suitable. However, there is not much research about its failure mode and assembled stiffness. The stiffness of shaped steel reinforced cemented soil retaining wall mostly comes from cemented soil, where about the stiffness of traditional SMW depends mostly on the stiffness of shaped steel. Bending tests were performed on 6 model composite beams with different cross section heights and with steel board as reinforcement. 2 kinds of loading scheme were adopted. The failure mechanism, assembled stiffness and ultimate bending bearing capacity of steel board reinforced cement soil beam composite were analyzed. Based on testing results and correlative analysis, the evolution of bending stiffness of composite beam can be clarified into two stages and the method to evaluate the bending stiffness at these two stages were suggested. The bending stiffness at the end of 1st stage is recommended to be used to predict the displacement of shaped steel reinforced cemented soil retaining wall when the factor of safety is satisfied.

Based on the finite element stress-strain analysis, the factor of safety of the slip surface is defined as the ratio of the critical shear intensity during failure to real shear stress, the authors utilize pattern search method to ascertain the critical slip surface of slope. Under the plane strain and homogeneous soil condition, this method is used to analyze the stability of embankment and excavation slope; and the result is compared with natural slope. It is shown that the shape of critical slip surfaces of the three kinds of slopes are similar; the factor of safety of natural slope is higher than the others. At the same time, the result of finite element method is compared with that of limit equilibrium method. Finally, the effect of soil parameters on the stability of embankment and excavation slope is analyzed.

Based on the theory for multiphase flow in porous media, analytical model for NAPL transport in soils is proposed and developed; and the transport behavior of NAPL in unsaturated soils and groundwater system is analyzed. Numerical simulation is employed to model the transport processes of LNAPLs and DNAPLs in subsurface system; and tempo-spatial distribution of NAPL and contamination extent are obtained. Numerical results show that the contamination characteristics of NAPLs can be reasonably described, which is significantly affected by intrinsic permeability of soils and residual saturation of NAPLs.

The effects of shaft mud cake and bottom sediment on bearing capacity of bored pile are simulated by using FEM software. Based on the calculated results of single pile bearing capacity under the conditions of different thicknesses and elastic moduli of bottom sediment, the effect rule of sediment on bearing capacity of bored pile is studied. The calculated results show that the effect of thickness of bottom sediment on bearing capacity is threshold and no more obvious than the elastic modulus when the thickness of sediment is over 300 mm.The effects of height and strength of mud cake on bearing capacity of bored pile are calculated by considering the effect of mud cake strength taken place of shaft friction deduction coefficient of shaft mud cake; and the results show that the main effect factor of mud cake on bearing capacity of bored pile is height of mud cake around pile shaft.

Landslide hazard is a serious natural hazard next only to earthquake and floodwater. It has brought about great losses to the economic and social development worldwide. Each year it causes a loss up to billions of dollars in the whole world. A striking amount of money has been spent on the prevention and redress of the hazard and much more losses have been incurred indirectly in addition. In China, mountains where landslide hazards happen frequently and densely cover 70 % of the area. China is among those countries stricken most by these hazards. These hazards give rise to loss with a total value of hundreds of millions Yuan and great damages to the country and people’s lives and properties. Since till now the damage and loss evaluation of secondary hazards has not been touched upon; the authors propose an evaluation model by making use of causal diagram combining failure tree analysis (FTA) and event tree analysis (ETA) to make reliability analysis of the secondary hazards system and forecasting of the losses thus arising from.

The stability of landslide is affected by the drawdown of reservoir water level. A polynomial constrained optimized model for soil-water characteristic curve and a new restrict function for overflow surface are put forward. Based on these, a saturated-unsaturated seepage program is edited with APDL in ANSYS. Zhaoshuling Landslide is taken as an example, firstly the physical model is established through Nuclear Magnetic Resonance and bore data，and then the seepage fields are simulated when the Yangtze River water level falls from 175 m to 145 m at different speeds, the stability of the landslide at different times is also analyzed. The result shows that the bigger the fall speed is, the least the minimum value of the stability coefficient is, and the earlier the value comes.

The rock mass discontinuity, owing to its property of self-similarity, can be addressed with the fractals although it is irregular in space and complex in network structure. The present study has testified the fractal characteristics of rock mass discontinuity distributions based on the calculation of the fractal dimensions of discontinuity distributions in the roadway surrounding rock masses at an underground mine with the application of the box-dimension method. By analyzing the fractal dimension values, this investigation shows that the higher the value is, the denser the discontinuity distribution, the longer the discontinuity traces, and the lower the rock mass quality; and it is shown that taking the fractal dimension of rock mass discontinuity distribution as the index of rock mass quality rating is feasible. By comparing the fractal dimensions calculated above with the corresponding rock mass grades classified by the standard for engineering rock mass rating, a scheme of rock mass quality classification, which takes the fractal dimension of the discontinuity distribution as the classifying index, is proposed.

From the theoretical analyses of data in several practical projects of gypsum stacks, a new disposal scheme for drainage and anti-permeance system of tailings dam is proposed. By setting a drainage layer under the gypsum stack, it differs from traditional drainage plans so that it can improve the drainage efficiency at the bottom of the stack and depress saturation line level. The new scheme not only improves the security of the gypsum stack, but also reduces its running cost. Furthermore, it has been put into practice in several tailings dam projects and has achieved outstanding effect. It not only provides an efficient theoretical foundation for the design of gypsum stack, but also gives important guidance for the anti-permeance design of other kinds of industrial residue deposit.

According to geological characteristics and formation mechanism of Xigoukou Landslide, the calculation and evaluation of landslide stability are performed in consideration of four kinds of loading conditions by transmitting coefficient method and FEM. Based on the results of stability analysis, the anti-slide piles and ground drainage are adopted as the harnessing measures of landslide. Some harnessing schemes are formed based on the results of transmitting coefficient method and FEM as the study samples for the evolutionary neural network. The landslide stability and construction cost of these harnessing schemes are evaluated respectively; and the nonlinear relationship of the designing parameters of anti-slide piles with safety factors and construction costs is established. Through the genetic algorithm, optimum designing parameters of anti-slide piles are searched out from above schemes; and the most optimally harnessing scheme is achieved. The stability examination and analysis by FEM show that this optimized scheme can satisfy the design requirements; and it is effective and economic to the landslide harness.

The mechanism and the design parameters for blast with air-decking is studied. The theory of detonation waves is adopted to investigate the processes of the one dimension expanding of the detonation products and motions of plane detonation waves within borehole. Interactions of a rarefaction wave with a interface and reflection on a rigid wall are also analyzed. The same courses of a shock are investigated. It decides the distribution of the pressure of explosion products changing with time along blast hole. Based on the up theory analysis, two conditions should be meeting for a reasonable range of the value of the air-decking ration in blasting rock. First, the ratio adopted should assure that the rarefaction wave from the contact interface between detonation product and air should reach to the bottom earlier than that of the reflected shock wave from the end of the stemming. Second, it also should assure that the reflected shock wave should be reach to the contact interface between detonation products and the air earlier than that of the reflected rarefaction wave from the bottom of the blast hole. Finally, a reasonable value for the air-decking ratio is decided theoretically in air-decking blasting. For different explosives, the reasonable range for air-decking ratio varies from 0.15-0.4. This result is well consistent with the values obtained from site carried out by previous researchers.

The particle swarm optimization(PSO) algorithm and the method of parameters inversion for gravity dam based on PSO algorithm were studied. According to this inverse method, the authors had analyzed its searching efficiency and quality at different population sizes; also evaluated its numerical stability. Results of computation example show that this method is simple and convenient; it has higher convergence accuracy and strong noise-resistant capability, so this inversion method for dam parameters is workable and reliable.

Numerical integration is one of the key techniques for numerical methods based on the nodes calculation. In order to meet the calculation requirements of the true meshless methods, an adaptive numerical integration algorithm for different integration domains associated with the position of the nodes is proposed. The method can be used to determine the integration region and its Gaussian integral points automatically. Two examples, i.e. a slope body which is up against vacancy and a square plate with a hole, are analyzed. The results show that the program based on the algorithms proposed have good boundary re-shape character and high accuracy. The program can be used as a general program module for the numerical methods and applied to practice. It is easily to interpret the program to other computer languages since its basic algorithms.

The secant shear modulus of lightweight sand-EPS beads soil (LSES) under dynamic loads will degrade with increasing strain. Based on cyclic triaxial test data on LSES of different cement contents and EPS contents, a degradation model of Gsec is set up relating to factors such as confining pressure, shear strain and cement content. After comparison, the Gsec model of LSES is similar with those of sand and cemented sand, that is, Gsec-?d is hyperbolic and Gsec is linear to . Additionally, due to the bonding effect of cementation, the confining pressure dependency of Gsec decreases with increasing cement content, which is responded by the parameter n. While cement content reaches to 10 %, the variation of n is not clear. This is because cementing strength increases to the level which makes the relative location between particles of LSES uneasy to change.

Tests on composite material from easy liquefaction fly ash and easy freezing silty clay according to dry weight 1:2 are conducted to investigate the dynamic properties of fly ash soils for roadbed filling. The dynamic triaxial tests are made on the two kinds of soils after freeze-thaw cycles. The variation law between the dynamic strength and the number of cycles of dynamic loading and the number of freeze-thaw cycles is obtained. The relationship curves of the dynamic stress-strain and the dynamic elastic modulus-elastic strain and the curve of the dynamic modulus and the number of freeze-thaw cycles are also given. The research shows that the dynamic properties of fly ash soils(1:2) is better than silty clay subjected to freeze-thaw cycles. After 3 cycles of freezing and thawing, its dynamic strength and dynamic modulus reach stability. It has superiority as roadbed filling.

The mechanism of road embankment reinforced with geotextile is studied with nonlinear finite element method. By comparative computing of the unreinforced road embankment with reinforced one, it is shown that the road embankment on soft soil foundation can be reinforced with geotextile effectively. The safety of embankment can be enhanced more than 20 ％ with geotextile, and the lateral displacement is reduced 15 %－25 %. Whether the vertical settlement could be reduced with geotextile or not, is dependents on the width of road and characteristic of foundation. With vertical settlement develops greatly, the lateral displacement at consolidation phase become less than that of construction phase. More exact instrument should be used to investigate the variation of lateral displacement at different construction phases. It is shown that there is no influence on dissipation of excess pore water pressure with geotxtile only. In order to reinforce the embankment effectively, it is advised that geotextile should be set on high-stress zone. Furthermore, the limitation of conventional limit equilibrium method used in investigating embankment reinforced with geotextile is analyzed.

Rock-soil aggregate mixture is broadly used in roadbed, dykes and dams for its favorable engineering properties. Shear strength of the mixture becomes the most important mechanical index for stabilization and deformation analysis because it always occurrs shear failure along the weakness surface in filler. However, it is difficult to determine the shear strength for the complexity composition, non-regularity frame distributing of the mixture, and restriction of current measure instrument. This study carried out shear test on different kinds’ and different dmax rock-soil aggregate mixtures by using the improved shear test instrument, determined the intensity of the mixture conveniently; meanwhile, reappeared the actual shear surface; and further more, directly measured the gurgitation data of the surface. According to the principle of fractal geometry, the surface has well fractal property; the gurgitation data was used to calculate the fractal dimension of the shear surface by program that based on cover method of triangle prism superficial area. Finally, the relationship, between shear strength of the mixture and the fractal dimension of shear surface, is established so as to forecast the strength of the mixture quickly.

Under uniaxial compressive and tensile loading, limestone’s meso-structure has been investigated by real-time under high temperature with advanced experiment instruments such as High Temperature Fatigue Testing System with Scanning Electron Microscope in Tsinghua University. Thermal damage evolution process, thermal crack growth and fracture characteristic of rock are discussed. The damage model of rock thermal crack growth is established. Combining test results with the concept of dislocation and diffusion creep, thermal damage deformation fracture mechanism of rock are researched. The results show that the thermal crack is intercrystalline crack mainly within the scope of 500 ℃.

Based on elastoplastic finite element model and Mohr-Coulomb yielding criterion, 2D FEM is applied to conduct numerical simulation research of stability of sliding avalanche slope during excavation in navigation route 1+016-1+080 of Longtan Hydropower Station; and the stress and displacement fields, plastic yielding area and effects of supporting system are analyzed. The results of simulation show that there appear continuous deformations during excavation and partly plastic yielding. The changes of groundwater level exert great influence on the slope; but the whole slope is still under stable condition. Meanwhile, the effective supporting measures are critical to improve the stability of slope during the excavation.

The interaction characteristics between reinforcements and soil are the key index in reinforced earth, which determines the stability of reinforced earth. Pullout test results show that the quantity of apparent frictional resistance between two-way geogrids and clay increases with the normal stress increasing. The failure format between two-way geogrids and clay is the entirety two-way geogrids pulled out when the normal stress is lower, but as long as the normal stress is higher than some certain quantity, the failure format between two-way geogrids and clay is changed from entirety pulled out to longitudinal gill pulled out. The apparent cohesion of entirety pulled out failure format is less than that of longitudinal gill pulled out failure format; and the apparent friction angle is reverse.

Pile-soil interaction plays important role in lateral loaded pile research. Soil pressure caused by interaction is the nonlinear function of displacement and depth. That is the displacement and stress of pile behaves nonlinear relationship, which results in complexity of analysis and calculation. In allusion to the complexity of the lateral loaded pile, it begins with Rankine’s earth pressure theory considering displacement. This paper deduces the calculation formula of soil pressure around the pile according to the displacement caused by deflection of pile. The formula can be used to calculate soil pressure based on displacement at any point without regard to foundation model. Compared to other analysis theory, this approach is simpler. In order to verify the rationality of the formula, authors take an example to set forth the process of analysis and calculation. The results are in accordance with the results of that p-y curve theory and practice.

The characteristics, designing, construction and checking methods of the advanced and applied underpinning technology, steel fiber pile technology, are introduced. In fact, the technology is rarely discussed or described in domestic works and even in the codes nowadays. But it’s really an excellent technology for underpinning construction of existing buildings for its rapid construction and reliable quality, especially for rebuilding of old cities and reinforcement of ancient buildings. The effect of the underpinning technology is also showed with some successful underpinning projects as well.

A series of laboratory tests were carried out to investigate the physico-mechanical properties of EPS beads-mixed lightweight soil which is made of sand and treated with cement. Results show that the compaction and moisture content of the treated soil have significant effects on its density and strength. There exist suitable compaction times and optimum moisture content. The effect of the moisture content during sample preparation on the stress-strain relationship was analyzed and linear relationship was obtained between the strength and cement content with fixed water-cement ratio.

Slope failures or even landslides are often triggered by improper excavation in high slopes cutting, whereas pre-reinforced anchor bolt presents an effective stabilization method. A new method is proposed for the design of pre-reinforced anchor bolt for retaining high cutting slopes. Pre-reinforced anchor bolt can stabilize the slope by constraining slope deformation and development of stress relief from overburden removal. The interaction as well as force transfer mechanism between bolt and rock mass are studied; and the results provide theoretical basis for the design of pre-reinforced anchor bolt.

Historical data of rainfall and landslides in Shenzhen City are researched in detail. And the partial correlation between landslides and rainfall, the correlation between landslides and rainfall intensity, and the statistic relation between landslide and rainfall time are analyzed. The results show that: First, the partial correlation coefficient is better between landslide and the two-days rainfall, and the sum of rainfall. It is clear that the regional landslides will appear when the rainfall reaches some numerical values. Second, the relation is very strong between rainstorm and landslides; the correlation coefficient is beyond 0.8, especially the great rainstorm and the unusual rainstorm. They can trigger landslides. Third, the occurrence time of landslide is parallelism to the rainfall season, the more is rainfall, the more is landslide. In addition, the occurrence time of landslide accords with or lags behind that of rainfall and rainstorm; but the lagged time is less than four days, and the landslide probably arises in the same day and the second day when the rainstorm takes place. The threshold values of critical rainfall and critical rainfall intensity are discussed. At the last, the indexes and grades of spatial early-warning are taken by the coupling between the model of landslide hazards and rainfall so that it predicts the time and space that the landslides occur.

In the deep aquitard, the clay soil was stiff and compact for the diagenesis. The flow of pore water in these clay soil layers may not obey Darcy’s flow. But the consolidation computation of deep aquitard still utilizes these consolidation equations that based on Darcy’s flow. In order to improve the precision of consolidation computation of deep aquitard, Non-Darcy flow (described by the threshold gradient il and exponent m) was incorporated in the one-dimensional consolidation equation of Terzaghi. And semi-analysis was used to solve non-Darcy flow one-dimensional consolidation equation of Terzaghi. A consolidation case was computed by Darcy and non-Darcy flow one-dimensional consolidation equation of Terzaghi respectively; and the authors found that (1) for the special degree of consolidation, the consolidation time would increase when non-Darcy flow was considered; (2) The calculation results of non-Darcy flow consolidation equation were consistent with the measured values.

The artificial neural network carries out the input and output nonlinear mapping relationship to predict the deformation of the partition frusta of the Three Gorge’s Permanent Shiplock by adjusting the connected weighted value and the network structure. The global optimal solution to the weighted value and the network structure is obtained by the optimized genetic algorithm. Combined the genetic algorithm with neural network, the characteristics of the deformation evolvement is identified. And then the time-effect deformation for the Three Gorges Permanent Shiplock is intelligently predicted; and it is shown that the proposed approach has higher predicting precision.