Earthquakes and landslides are two major geological disasters causing huge casualties and economic losses each year across the world. Both landslides and earthquakes can be shown in a model of double blocks separated by a sliding plane. The key for geo-disaster prediction is the Newton force variation along the sliding plane. However，the measurement of the Newton force on the sliding plane is extremely difficult. Therefore，most of the current researches on earthquakes and landslides rely on the displacement monitoring between the two blocks. The relative displacement between the two blocks is considered as the necessary condition but not the sufficient condition for the occurrence of the earthquake and/or landslide，which may be the reason for the general recognition of the limitation on geo-disaster prediction. The presentation introduced a study on the theory of double-block mechanics(DBM) including the measurement of the Newton force，which is the necessary and sufficient conditions for initiating a geological disaster due to the block motion，using the so-called constant- resistance and large-deformation cable with negative Poisson?s ratio effect. Applications for geo-disaster prediction were also described in this presentation.

Flexural toppling failure is one of the most common failure types of counter-tilt slopes of layered rock. There are many questions need to be solved currently. The failure process and mechanism of the flexural toppling of counter-tilt slopes of layered rock were clarified based on the analysis of model test results. The mechanical model and stability analysis method of the flexural toppling of counter-tilt slopes of layered rock were established on the basis of the limit equilibrium theory for cantilever beams，and a special computer code was developed to provide rapid evaluation of slope stability for the flexural toppling of counter-tilt slopes of layered rock. Finally，two case studies were illustrated for practical verification of the proposed approach，and a parametric study was conducted. Some conclusions useful for design and construction of these types of slopes were drawn.

The propagation of stress wave in jointed rock under different in-situ stresses was studied through model test considering the influence of the joint number. An equation of wave propagation across multiple joints under in-situ stresses was established. The blasting stress wave was generated by the detonating cord，and the stress was monitored at different positions. The composition of wave attenuation induced by the jointed rock was studied under in-situ stresses，and the influence of confining pressure and joint number on the wave attenuation was analyzed. Considering the influence of in-situ stresses on nonlinear joint model，the equation of stress wave in multiple nonlinear deformation joints under in-situ stress was derived based on the method of time domain recursive analysis. The results show that the wave attenuation in the jointed rock is induced by the combined effect of the rock material and the joints. With the increasing of the in-situ stresses，the attenuation of explosive wave in the jointed rock is enhanced，in which the wave attenuation induced by rock material is strengthened and the attenuation caused by joints is reduced.

Widely distributed shattered slopes are potentially high-risk carriers of geological disasters in earthquake areas especially in the rainy season. A slope in Sanxicun was studied as an example in this paper. Based on the detailed site investigations，the effect of rainfall was investigated with the Seep model. The strength parameters under different conditions were acquired in the laboratory tests. The deformation and destructive mechanism of the shattered slope triggered by rainfall were summarized. The slope stability in the light of the actual situation and the corresponding mechanical model was calculated. The sliding process of the shattered bedding slope was divided into five stages such as the original status，earthquake damage，creep weakening，rainfall triggering and sliding. Rainfall was found to be the main reason to form deep cracks，expanding joints and massive rock strips. At the same time，the cracks promote the rainfall infiltration，resulting in water softening，creep deformation and finally sliding. The main factor to affect the stability of the slope is the interaction of rainfall and creep after the earthquake.

Determining the reasonable safety standard for high rock slopes under blasting vibration is one of the keys in the excavation control of foundation surface of arch dams in the Southwest of China. Currently，the peck particle velocity of the last bench is used as the control standard. On this basis，the determination of control standard for high rock slopes was analyzed. The formation of blasting damage zone was investigated. The radial and tangential stresses are the main factors of the blasting damage. Therefore，the directions should be considered in the determination of blasting safety control standard. The velocity in horizontal radial and tangential directions used as the control standard is more reasonable. The distribution characteristics of the blasting vibration around the berm was analyzed. The characteristics of the local amplification was found. A test approach of blasting vibration was proposed. When the blasting vibration control standard is used to distinguish the response of the high rock slopes，the test points should be fixed on the inside of the berm. If the most adverse effect of berm of the last bench is the target，forever，the test points must be fixed on the outside of the berm.

Madaling landslide is a typical mining induced landslide，of which the natural slope is a gently counter- inclined layered structure. In this paper，the physical modeling method was used to study the deformation process of the mining slope under the two layer mining condition and the geomechanical mode of the slope deformation was analyzed. After the coal mining，the stress concentration occurs in the overlying rock of goaf boundary leading to rock cracking initially mainly in the vertical direction. The mining fissures expand to the centre of goaf and gradually form the abscission fissures and shear fissures. After the deformation becomes stable，the overlying rock strata of goaf were bended to form a subsidence area on the surface. Due to the pushing of goaf overburden subsidence，the outer slope slides along the coal seam resulting in the uplift of the lower part of the slope. The geo-mechanical model of this kind slope deformation and failure can be divided into the bending-tensile (“supergene” transformation stage)，plastic flow-tensile and creep-tensile three stages.

In the freezing-thawing environment，temperature is one of the key factors influencing the physical and mechanical characteristics of rock. However，the thermal transfer and temperature change in rock in the freezing-thawing test have not been fully understood. The experimental and numerical methods were therefore applied to analyse the process of heat balance. Three kinds of rocks were studied in the freezing and thawing tests with the temperature being monitored. The process of central temperature change contains in three stages such as the precooling stage，the phase transition stage of moisture and the cryogenic stage during freezing，and the process during thawing includes the preheating stage，the phase transition stage of moisture and the deep heating stage. The phase transition stage is special and significant in the freezing and thawing test. The temperature of phase transition is between 0 ℃ and －1 ℃ for all the specimens. As the temperature range increases，the durations of each stage in the freezing and thawing processes are different. The total duration decreases gradually in the freezing process，but decreases first and then increases in the thawing process. The processes of freezing and thawing for the saturated rock were analyzed with the software of Comsol Multiphysics considering the phase transition of moisture. The results of numerical simulation match well with the test results. According to the numerical simulation results，the characteristic differences of the freezing and thawing process are mainly in the phase transition stage and the porosity of rock influences the stage greatly. The residual of heat potential results in the differences between the symmetrical and unsymmetrical temperature range in the freezing and thawing process.

A large scale field test bench for prestressed bolt was manufactured to study the distribution characteristics of the prestressed field around the end-anchored bolt. The results show that the distribution pattern of the prestressed field of a single anchor is similar to the shape of pomegranate. The stress contour surfaces vary gradually from dense to sparse，the stress values descend gradually and the distribution ranges enlarge gradually. Two concentration zones of compressive stresses form in the rock in the vicinity of the anchorage and a concentration zone of tensile stress forms near the anchor head. The distribution of the stress along the axis of the bolt is related to the distance between the measuring line and the anchor bolt. The variation of the stress along the horizontal direction is related to the distance between the measuring line and the surface of the model. Although the pre-loads are different，the stress field distributions are basically the same，but the distribution ranges of the stress contour surfaces change significantly.

Uniaxial compression AE test of granite was carried out. The energy，dominant frequency and amplitude of dominant frequency of AE signal in the process of granite burst were extracted to study the three kinds of coupling relationships between the rupture length and energy，between the energy and amplitude of dominant frequency and between the energy and dominant frequency. The correspondence between the rupture scale and AE signal characteristics(energy，amplitude and dominant frequency) was discussed in terms of energy. The variation of AE signal corresponding to the different rupture scales in the course of rock fracture was the focus of the study. The AE precursor of rock burst was investigated. Four modes of AE signals in the process of granite rupture were found，including the low frequency and high amplitude，the low frequency and low amplitude，the intermediate frequency and low amplitude，and the high frequency and low amplitude. In the process of granite rupture，the characteristics of large scale fracture AE was characterized by the low frequency，high amplitude and high energy，which corresponded to the AE signals of low frequency and high amplitude. The AE characteristics of small scale rupture showed the low amplitude and low energy，coexistence of the low，medium and high dominate frequency，corresponding to the three modes of AE signals：the low frequency and low amplitude，the intermediate frequency and low amplitude，and the high frequency and low amplitude. There are three modes of AE signals：the intermediate frequency and low amplitude，the high frequency and low amplitude and the low frequency and high amplitude，which are suitable as the main signal source for the prediction of the rupture of granite. The characteristics of the precursor are as follows：the intermediate and high frequency low amplitude signals disappear gradually，and the low frequency high amplitude signals appear，which is the phenomenon of the medium and high frequency low amplitude signal being quiet and the low frequency high amplitude signal being not quiet. The precursor response coefficient of the high frequency low amplitude and low frequency high amplitude signal is 0.2，and the one of the intermediate frequency low amplitude signal is 0.14. The precursor of response time of high frequency low amplitude and low frequency high amplitude is earlier.

The impingement of rocks by the high-velocity water jet causes the erosion of structures. The failure patterns of rocks subjected to water jet with different velocities vary greatly. The stress wave effect of water jet impacting on rock was analyzed based on the previous studies. A number of impacting experiments were conducted with the water jet velocities of 157，316，447，547，632，707 and 774 m/s respectively. According to the failure phenomenon of sandstone，the number，size and patterns of cracks inside the rock subjected to the water jet with different velocities were analyzed. Finite element models of water jet impacting on the cylindrical sandstone were established. The propagation of stress wave and the generation of cracks in rock were studied. The broken pit and the circumferential cracks on the surface of sandstone occurred when the velocity of water jet was above about 72 m/s，and the former was produced by the shear stress of water hammer pressure and the later was induced by the tensile component of Rayleigh wave. Many transverse cracks were produced by the radial tensile  stress waves when the velocity was between 300 and 700 m/s. The major failure pattern of sandstone is the split cracks when the velocity is above 700 m/s.

Hazard regionalization of debris flow disasters along highways clarifies the priorities of disaster prevention and protection standards for different parts of China，and provides a theoretical basis for macro policy formulation. Hazard sources of debris flow disasters along highways were identified from four aspects of the topography and landscape，precipitation，rock and soil materials，and vegetation. The hazard assessment indexes were extracted using the genetic algorithm according to the survey results of the potential debris flow disasters along highways. The weight of each index was calculated through the AHP algorithm improved by the cloud model. The assessment index maps were rendered and the spatial hazard analysis of debris flow disasters along highways was made with ArcGIS. Hazard regionalization scheme of debris flow disasters along highways in China was worked out mainly based on the hazardous degree. The hazardous degree of debris flow disasters along highways in China is from 1.000 to 7.900. High hazardous areas are the mountainous areas in the southeast of Zhejiang and Fujian province，the mountain areas of Taiwan，Kunlun Mountains，Tianshan Mountains，Taihang Mountains，Loess Plateau，Hengduan Mountains and eastern Tibetan Plateau. China is divided into regions of low hazard，moderate hazard，severe hazard and extremely severe hazard. The extremely severe hazard areas are the Loess Plateau—Qinba mountain areas，Wuyishan—Taiwan mountain areas，Sichuan-Yunnan mountain areas and Tianshan-Kunlun mountain areas.

Seismic performances of anti-slide piles with anchor cables are the basis for establishing and improving their seismic design method. To reveal the seismic behaviors of anti-slide piles with anchor cables，the project of anti-slide piles with anchor cables reinforcing the Beihou mountain landslide was taken as the reference prototype，and the corresponding 50 g model on centrifugal shaking table for simulating the prototype performances was built. The bedrock waves at Qingxi station during the Wenchuan earthquake were exerted as the base excitation in the model tests. The historic data of accelerations on the surface and inside the landslide reinforced by anti-slide piles with anchor cables，the strains of pile，the dynamic soil pressures between the landslide body and the anti-slide piles and the axial forces of anchor cables were recorded. The variations of landslide accelerations，bending moments of anti-slide，dynamic soil pressures between the landslide body and the anti-slide piles，axial forces of anchor cable were revealed from the above data.

Many tunnels have been constructed in phyllite rock and the displacement criteria in safety control for phyllite tunnels has become an urgent problem to be solved. The Dujiashan tunnel of Guang(Yuan)—Gan(Su) expressway passing through the Wenchuan earthquake zone was studied. The deformation under different buried depths，construction methods and supporting parameters in broken phyllite of grade V was studied with indoor model tests and field tests. The results indicated that the depth influenced the tunnel deformation more than the construction methods and the supporting pattern did. The vault settlement was considered as the main control indicator，and the line cracking was considered as the symbol of stability of the broken phyllite tunnel. The field dada was analyzed statistically. A displacement criteria of safety control during the construction under the conditions of the buried depth＜300 m，three benches(reserved core soil) and supporting pattern of F3–F5 in broken phyllite tunnel was established.

In order to study the failure mechanism of deep floor rock，a model of mining cracking and conduit formation in floor rock with small faults was established based on the test system developed in-house with high water pressure to simulate the floor water inrush. The stress and displacement sensors were set up at different depths of the floor，and the stress and displacement of the floor and the fault rock around the mining face were studied. The crack development and propagation in the floor and fault rock was derived with the inverse simulation. Two trends of the stress in the floor rock during mining at the working face occurred. In the first case，the stress increment in the floor rock under the pillar on the left open-off cut increased at first and then decreased. In the second case，the stress increment in the floor rock under the stope increased at first，then decreased to zero and finally increased at the opposite direction. The deep mining cracks mainly appeared in the corresponding floor of open-off cut，goaf and mining working face dominated by the vertical tensile cracks，shear cracks and layer cracks. Some small cracks were generated from the tips of the main crack. The larger stress differences were formed in the hanging wall and the footwall rock of fault close to the coal seam. A strip of long shear crack parallel to the fault strike was presented in the fault hanging wall due to the large shear stress difference，which promoted the sliding and the fault activation.

The creep behavior of over-consolidated soft clay was studied through plane strain tests for undisturbed soft clay using a new measuring device. The results show that the new measuring device can measure the lateral deformation of over-consolidated soft soil under plane strain and eliminate the influence of the accuracy in volumetric deformation measurement. There is a good correlation between the lateral deformation and the over-consolidation shear stress ratio (OCRq)，and the OCRq reflects the effects of shear stress and stress history on the lateral deformation. Both the volumetric creep coefficient and the axial creep coefficient have a good correlation with the OCRq. On the basis of the plane strain creep tests to the over-consolidated soft soil under different principal stress ratios，an empirical model with four parameters was developed. The variables in the model are the principal stress ratio and OCRq. The empirical model takes into consideration of the normally consolidated state of soft soils and reflects reasonably the influence of principal stress ratio and stress history in the creep process under plane strain condition.

Modified carboxymethyl cellulose sodium exhibits the strong dialysis cementation and adsorption behavior on the surface of soils and rocks. When the slope surface is covered with a layer of soil mixed with the modified CMC of an appropriate concentration，a protective soil layer against the erosion with the thickness of 12–15 cm is created. Silty sand samples taken from the surface of excavation slopes alongside a highway were mixed with the modified CMC of different concentrations. The shear strength tests，the disintegration tests，the permeability tests and the tests under freezing-thawing cycles were carried out to obtain the basic physical and mechanical characteristics of the mixture. The test results show that，with the increase of the concentration of the modified CMC，the hydraulic stability and shear resistance increase and the permeability decreases. When the soil is mixed with 1.1% of the modified CMC，the disintegration phenomenon disappears，and the cohesion and the friction angle are respectively，1，2 and 0.8 times greater than the samples without the modified CMC. The permeability coefficient changes from 2.17×10－4 cm/s to 1.0×10－5 cm/s，and the loss of the strength due to the freezing-thawing is less than 25%. The erosion gully of 13 cm wide and 9.0 cm deep appears on the slope without the modified CMC and the erosion area occupies 30% of the surface area. For the slope with the modified CMC，no erosion phenomenon appears after one hour of rainfall. The modified CMC has already been applied to serval construction site successfully.

In recent years，artificial freezing method has widely been used in the construction of connection tunnel between metro tunnels. The engineering properties of soil change under the freezing-thawing action. In this paper，the dynamic characteristics of frozen-thawed soil were studied with the undrained dynamic triaxial test in laboratory to simulate the effect of artificial freezing. Dynamic pore pressure of remolded clay was measured during the cycles of freezing and thawing. A new pore pressure model was proposed. The microstructure change of soil during the cycles of freezing and thawing was analyzed with the scanning electron microscope(SEM). The macroscopic characteristics of deformation were revealed from the microscopic perspective. The lower the freezing temperature，the faster the development of pore pressure and the larger the stable value under cyclic loading. With the increase of freezing-thawing cycles，the weakening effect of soil structure increases. The freezing-thawing action breaks the link between the soil particles，resulting in the re-arrangement of grain skeleton and the development of large micro-pore. Then，structural weakening effect occurrs which leads the structure into the instable state. Due to the external energy，the internal structure tends to be steady during cyclic loading. The decrease of the volume of macro pore further leads to a more significant compaction of frozen-thawed soil，which causes the accumulation of excess pore pressure and the development of deformation in macro perspective. Multivariable nonlinear fitting of pore pressure described by the composite exponential model based on the experimental data was proposed and the proposed pore pressure model fit the data well.

In order to understand the unsaturated host medium of the high-level radioactive nuclear waste disposal repository in deep geological formation，a series of hydration and dehydration tests were performed on the hard clay which has been considered as the potential host medium for storage of the high-level nuclear waste. A suction control device was developed and the effects of suction cycles and suction gradients on the hard clay were investigated. The results showed that the suction gradient had little effect on the suction-water content relation，while the suction cycle has great effect on it，particularly the first cycle of hydration and dehydration. Nuclear magnetic resonance(NMR) method was used to study the water distribution during desaturation. The experimental results showed that the   curves gave the evidence of the dependence of water content of the hard clay on the suction. The relationship between the water distribution and the pore size distribution was established. The water content variation during the hydration and dehydration depends on the state of adsorbed water. 

To investigate the horizontal vibrating characteristics of large-diameter pipe piles，a governing equation with Timoshenko model assumed for pipe piles was established. Methods of differential transformations and variable separation were adopted to decouple the three-dimensional equations of soil. The implicit analytical expressions of the soil displacements and horizontal impedances were deduced. Analytical solutions of the pile response were derived based on the assumption of perfect contacts between the pile and soil and thus the expression of the complicated impedances was obtained. On the basis of the analytical solutions，parametric analyses were carried out to find out the most significant factors influencing on the behavior of the horizontal vibrating pipe piles. The results show that the variation of horizontal complex impedances deduced according to the Euler-Bernoulli model agrees well with that deduced from the Timoshenko model，which validates the solution. The real parts of the complex impedances decrease with the increase of the pile length and vice versa for the imaginary parts. Both the real parts and imaginary parts show little variation when the pile length reaches the certain critical value. Although the complex impedances increase with the decrease of the inner radius，their influences on the complex impedances are marginal when the inner radii are less than 0.2 m. Both the average radius and wall thickness of the piles significantly influence the complex impedances when the cross sectional areas are approximately equal.

The long-term soil settlement was monitored around a tunnel within the range of 1.5 times of the outer diameter of the tunnel of Metro line 9 in Shanghai. A parameter was introduced into an existing dynamic elasto-plastic constitutive model to take into account the effect of long-term cyclic loading. The development of soft clay settlement caused by the train vibration and post-construction consolidation was calculated using the improved constitutive model. The measured settlement of the tunnel invert relative to the ground is 4.7 mm after 850 days of tunnel operation. The calculated settlement is 4.6 mm with the vibration-induced settlement to be 3.1 mm. The difference of measured and calculated settlements is 2%，indicating that the improved constitutive model shows a satisfactory performance on simulating the accumulated deformation characteristics of soft soil under the vibration load. The long-term settlement of the tunnel is in accordance with the exponential growth law with time. In the case of tunnel depth at 13.2 m，the relative settlement of arch bottom tends to be stable after about 8 years，and the relative settlement is 4.2 mm after stability.

The isotropic compression tests and triaxial shear tests were carried out for 3 different groups of sand. The mechanical properties of sand were analyzed in detail. A certain amount of particle breakage occurred under high pressure，which changed the shear energy consumption and led to a transition from shear dilation and softening to shear contraction and hardening. The particle size of sand and the confining pressure affected the peak stress ratio of sand. The classical M-C strength criterion was found to be not applicable anymore under the high pressure condition. However，the strength formula of the residual stress ratio was hardly affected by the particle size and the confining pressure. The residual stress ratio was a typical cohesionless frictional geomaterial property. The sand showed notably critical state phenomenon in the shearing process from common pressure to high pressure. Both the critical state curve and the isotropic compression curve declined exponentially and crossed each other under the high pressure. Two curves together constituted the state interval of sand which reflects the shear dilation and shear contraction.