Large-scale shaking table tests on a layered rock slope with a size similarity of 1∶100 were conducted based on the Ganmofang landslide in Anxian，Sichuan province, and the dynamic response and failure mechanism of the layered rock slope under earthquakes were studied by successively loading seismic waves with different amplitudes，frequencies and durations. The results show that the frequency and amplitude of seismic waves have great influences on the acceleration dynamic response of the slope. The horizontal PGA amplification factors increase with increasing the frequency of input seismic waves when the input frequency is less than the initial natural frequency of the slope. However，the horizontal PGA amplification factors decrease with increasing the input frequency when the input frequency is greater than the initial natural frequency of the slope. The horizontal PGA amplification factors also increase with increasing the amplitude of input seismic waves when the input frequency is less than the initial natural frequency of the slope. However，the influence of lower amplitude seismic waves on the horizontal PGA amplification factors is more significant when the input frequency is close to or greater than the initial natural frequency of the slope. It is also shown that the duration of seismic loads has no obvious influence on the dynamic response of the slope. Analysis of both the induced displacement of the slope and the video recording of the test shows that the displacement dynamic response at the slope crest is more significant compared with other parts of the slope. When the amplitude of input seismic waves is 0.6 g，the slope is in a critical state with a critical displacement of about 7.3 cm，the determination of which is the basis and prerequisite for the evaluation of slope stability under seismic loads by using critical displacement in subsequent studies. The failure mechanism of the layered rock slope under seismic loads is loosening and cracking of the slope crest，uplifting of the lower part of the slope，developing and connecting of the potential sliding plane from the slope crest to the lower part of the slope，and finally shallow landsliding. The present study reveals the dynamic amplification effect and failure mechanism of layered rock slopes under seismic loads，and provides a useful reference for the seismic resistance design of engineering slopes and the prevention and reduction of disasters.

In order to study the mechanical properties and seepage characteristics of red sandstone under different high temperature environments，seepage tests under hydrostatic pressure conditions and triaxial compression conditions were carried out by using the Rock Top multi-field coupling tester. The results show that，at different temperatures，the pressure difference，the flow rate，and the increase and decrease rates of the seepage flow are consistent with the damage evolution trend，and that the seepage state consists of three stages. Before the damage stress，the rock sample is mainly compressive deformation，the fluid overflows reversely and the seepage process is interrupted. At the initial stage of the unsteady rupture development stage，the flow rate increases sharply while the pressure decreases sharply，accompanied by a first rapid increase，then rapid decrease and finally slow grow of the permeability with a pseudo-peak. The permeability presents a true peak before the residual stress. Within different temperature thresholds，the thermal stress has different effects on red sandstone. The initial，peak and post-peak permeabilities and the strength increase first and then decrease with increasing the temperature. At a certain temperature threshold(between 100 ℃ and 150 ℃)，the development of internal cracks in the rock is mainly controlled by the confining pressure. The permeability of rock samples at different temperatures(100 ℃，50 ℃ and 25 ℃) and different seepage pressure gradients changes with the confining pressure following a power function，and the change trends of the permeability with the pressure obtained by the transient state method and the steady state method are consistent with each other. Under the same seepage pressure gradient，the permeability by the transient state method(10－19 m2) is 2 orders of magnitude higher than that by the steady state method(10－21 m2)，reflecting the regularity of the rock permeability with the temperature and the confining pressure. At the same confining pressure，the higher the temperature，the greater the difference between the permeability values measured by the two methods，and at the same temperature，the steady-state permeability of the rock sample under different seepage pressure gradients is of the same magnitude. Under the high hydrostatic pressure，the influence of the permeability gradient on the permeability is not obvious. The hydrostatic stress is an important reason for the permeability，while The temperature and the seepage pressure gradient on the permeability is limited. Both methods show that red sandstone is a typical low-permeability rock.

In order to predict the rockburst tendency level more accurately，shear stress of surrounding rock，ratio of shear stress of surrounding rock and compressive strength，brittleness index and elastic deformation energy index are selected as the prediction indexes of rockburst tendency level according to the cause and characteristics of rockburst，and the improved CRITIC algorithm is used to weight the indicator samples. A new machine learning algorithm named as XGBoost is introduced to perform computational training on the samples，and a CRITIC-XGB model of rockburst tendency level prediction is established. The model is used to predict the rockburst tendency level of the collected rockburst instances，and the prediction results are compared with those by XGBoost，random forest(RF) and support vector machine(SVM) algorithms. The research results show that the convergence performance of the CRITIC-XGB prediction model is significantly improved compared to the single XGBoost model and that the CRITIC-XGB prediction model has higher prediction accuracy than the single XGBoost，RF and SVM algorithms. The developed model provides a new and reliable method for the prediction of rockburst tendency grades.

Rockbolt support system is an important technical approach to control the dynamic disasters that occurr in deep underground engineering with brittle surrounding rockmass，but the dynamic anchorage theory still lags behind the engineering practice. In this investigation，the indoor similar physical model test was performed to research the dynamic response law of rock mass with anchors under lateral impact loads. The influences of the impact energy and the mechanical characteristics of the anchor on the mechanical behavior of rock mass were analyzed. The test results show that shear and flexural fractures are the mainly mode of the rockmass with anchors，and that the inclined fractures in the middle span at about 45°with the normal direction are dense. The strength and toughness of the rockbolt can inhibit the development of the cracks of the rockmass，especially the connected cracks. The higher the rockbolt strength，the greater the impact absorption energy，the smaller the crack opening of the anchored rockmass，and the stronger the overall energy absorption capacity of the anchored rockmass. The impact velocity and the rockbolt strength affect the impact force of the drop weight and the axial force of the rockbolt. Specifically，the larger the impact velocity is，the larger the platform values of both the impact force and the axial force of the anchored rockmass are，and the shorter the corresponding action time is. The higher the rockbolt strength，the larger the platform value of the impact force，the shorter the impact time and the larger the slope of impact force attenuation. Rockbolt can significantly enhance the peak strain and improve the tensile strain state of the rock surface. Totally，the strength and the toughness of the rockbolt have a significant impact on the impact resistance of the rock mass. The impact resistance of the rock mass can be improved by improving the strength and the toughness of the rockbolt.

The dynamic mechanical behaviour of filled rock joints and its influence on stress wave propagation are important bases for dynamic response analysis and safety evaluation of rock mass engineering. In view of the lack of research on the cumulative damage and the strength weakening of filled joints by dynamic loading disturbance，series of tests are carried out on the artificial filled jointed rock samples to study the damage evolution rule under the cumulative impacts and its influences on the dynamic mechanical properties in this present paper. A simply equipped drop hammer impact device is used to carry out multiple pre-impact tests on the jointed rock samples，then the cumulative damage law is analyzed through the change of the wave velocity. On this basis，the dynamic impact tests of SHPB are carried out on filled jointed rock samples after different numbers of pre-impact. Based on the test results，the influence of cumulative damage on the dynamic mechanical properties of the filled jointed rock is analyzed from the aspects of strength deformation characteristics，wave propagation characteristics and energy dissipation.

Based on uniaxial compression tests of Furong Baijiao coal rock under quasi-static strain rate[10－5，10－2] s－1，the energy evolution law of coal rock deformation and failure process under different strain rates was analyzed. A new method for determining the characteristic stress of coal rock by using energy dissipation rate curve and lateral strain difference was proposed，and the variation law of the characteristic stress under the category of quasi-static strain was analyzed. The results show that the energy evolution of coal rock under different strain rates can be divided into three stages including crack closure，linear elasticity and rapid crack propagation，and the energy dissipation rate curves all show a trend of rising first，then falling and next rising in the pre-peak stage. The maximum and the minimum points of the energy dissipation rate curves are respectively defined as the crack closure stress  and the damage stress ，and the lateral strain difference is calculated to determine the crack initiation stress  combined with the obtained damage stress. The ratios of the characteristic stress to the peak stress of coal rock under different strain rates are compared，showing that all three ratios decrease with increasing the strain rate. Finally，the limitation of the traditional methods and the rationality and accuracy of the new method are compared and analyzed，and the engineering significance of the strain rate effect of the characteristic stress is proposed.

To explore the influence of the confining pressure on energy evolution characteristics of loaded rock samples，the experimental stress path of constant confining pressure and unloading axial pressure is designed by applying a constant axial displacement increment at the same time interval，and triaxial cyclic loading and unloading tests under six confining pressures are carried out using the MTS815 rock mechanics test system. A method for calculating rock energy based on the area formed by the loading and unloading curves is proposed，which avoids the energy calculation error caused by the assumption of constant elastic modulus. The characteristic energy density and energy consumption ratio are adopted to define the energy accumulation，dissipation and release behaviors of loaded rock samples，and the confining pressure effects of the energy evolution process and energy distribution law of the loaded rock sample are revealed. The test results show that with the passage from the pre-peak to the post-peak，the elastic energy ratio gradually decreases，whereas the proportion of the dissipated energy gradually increases. The proportions of both elastic and dissipated energies tend to be stable in the residual phase. The characteristic energy density of rock samples also increases with the increment of confining pressure. The energy consumption ratio，which is defined as the ratio of the dissipated energy density to the elastic energy density，can characterize the internal damage accumulation state of the loaded rock samples. In the pre-peak stage，the energy consumption ratio undergoes a change from increasing to decreasing，and there is an inflection point that corresponds to the symptom point of large-scale cracking or destruction of the loaded rock samples. The confining pressure can suppress energy dissipation and release due to the fracture or failure of rock samples，resulting in incomplete release of the elastic energy when the rock sample is damaged，and the energy consumption ratio is negatively correlated with the confining pressure.

Rock mass integrity，which can be obtained effectively according P-wave velocity, is an important factor for evaluating rock mass quality. To overcome the problems of too much subjectivity and insufficient precision in the traditional evaluation process using empirical formulas，a new multi-scale rock mass integrity index(MRMII) and corresponding evaluation method are proposed based on weighted random forest(WRF) algorithm and P-wave velocity data. The MRMII，comprehensively considering various key parameters such as the P-wave velocity along the hole depth，unloading conditions，hydrogeology，buried depth and lithology，is calculated by the proportions of various rock mass integrality in WRF model prediction results. An actual engineering application shows that the calculation values of the MRMII are consistent with the field surveys，showing that the MRMII can be used to refine evaluation of rock mass integrity in different scales. In addition，compared with the traditional P-wave testing method，the MRMII can reduce the impact of measurement errors and insufficient engineer experience on classification results and obtain more suitable results for guiding engineering construction.

In order to study the influence of the water content，the effective stress and the fracture compressibility on the permeability of coal during deep coal mining，isothermal adsorption test and seepage test of coal under different water content conditions were respectively performed by using HCA-type high-pressure capacity method adsorption device and gas-containing coal thermal-fluid-solid triaxial servo seepage device. A coal permeability model considering the combined effect of the water content and the fracture compressibility was established，and the change law of the effective compressibility coefficient and the permeability of coal under different water content conditions was analyzed. The results show that，when the gas pressure is constant at 1 MPa，the axial and radial strains of coal increase with increasing the effective stress，and that，when the effective stress is constant，the axial and radial strains of coal and the gas flow decrease gradually with increasing the water content. As the gas pressure increases，the coal gas adsorption capacity first increases and then tends to be saturated after the gas pressure reaching a certain value between 1 and 2 MPa. Under the same water content，the permeability of coal decreases with increasing the effective stress. When the effective stress is constant，water has a limiting effect on the permeability of coal，in other words，the permeability decreases with increasing the water content. There is a negative correlation between the adsorption deformation and the effective compressibility coefficient at different water cuts，and the effective compressibility coefficient has a negative correlation with the water cut. The calculated permeability by the developed model is basically consistent with the measured，showing that the developed model can better characterize the evolution law of the coal permeability with increasing the effective stress under different water content conditions.

The hazard assessment of earthquake-triggered landslides(ETLs) is an extremely crucial component of risk assessment and geohazard prevention and reduction in strong seismic mountainous areas. 1 022 co-seismic landslide polygons in the Jiuzhaigou National Geopark triggered by the 2017 Jiuzhaigou Mw 6.5 earthquake were selected as the data sample and 1 234 slope units were divided by the r.slopeunits software as the modelling units. Selecting the peak ground acceleration(PGA) and 12 topographic，geological and hydrological parameters as the selected triggering factor and the conditioning factors of ETLs respectively，the mean landslide occurrence probability and uncertainty(95% credible interval) under eight key historical earthquake cases during the period between 1933 and 2017 were determined based on the Bayesian probability method and generalized additive model. The 10-fold cross-validation results of the initial model built with the landslides triggered by the 2017 earthquake show that the average AUCROC value，representing the spatial prediction capability of the model，arrives to as much as 0.93，indicating the reliability of the landslide occurrence probability simulation results corresponding to the other seven earthquake cases. PGA plays a dominant role leading to the occurrence of ETLs in the study area and the landslide probability has a clear positive correlation with PGA. The overall high landslide probability area is distributed in a long belt shape along the valleys. This paper provides a new method and approach for comprehensive hazard assessment of ETLs and the results can be reference for the prediction of the probability of future ETLs and quick assessment after earthquake for the study area.

The classical earth pressure theories were established by studying the stress state in an elastic half-space body based on the limit equilibrium condition of soil and the static equilibrium of the wedge. Due to the creep and consolidation characteristics of soil，the active and passive earth pressures have time-dependent features. From a long-term perspective，the earth pressure acting on retaining walls due to the creep and consolidation of soil is under non-limit equilibrium conditions(limited displacement). A calculation formula for calculating the earth pressure acting on the retaining wall under limited displacement is established in this study based on the linear elastic constitution theory. The tangent modulus in Duncan-Chang nonlinear elastic model is introduced to reflect the change of soil modulus with confining pressure，and the boundary strains of Rankine active earth pressure，earth pressure at rest，principal stress direction deflection and Rankine passive earth pressure are derived. According to the four boundary strains，the earth pressure acting on the retaining wall is divided into five state zones as active failure state zone，active earth pressure state zone with limited displacement，passive earth pressure state zone with limited displacement before principal stress deflection，passive earth pressure state zone with limited displacement after principal stress deflection and passive failure state zone. By comparing and analyzing the calculation results by the proposed formula with the model test results，it is concluded that the earth pressure distribution of the wall is always non-linear when the retaining wall moves in a mode of translation displacement (T mode)，rotation displacement around the wall base(RB mode) or translation + rotation displacement around the wall base(RBT mode)，and that the calculated values of the earth pressure along the wall depth under different displacements are basically consistent with the measured values，which indicates that the proposed can be well applied to the design of retaining walls in practical engineering.

In order to study the effect of the vibration frequency and the phase difference on the two-way dynamic modulus and the damping ratio of silt sand，a series of tests under the action of compression and torsion coupling were conducted using the hollow cylindrical torsion shear apparatus. The results show that，under the coupling action of two-way dynamic loads，the vibration frequency and the phase difference have certain effects on the axial dynamic stress-strain relationship and the torsional shear stress-strain relationship while no effect on the dynamic shear modulus of silt sand. The initial dynamic shear modulus with the phase difference = 90° is the largest. The vibration frequency and the phase difference have a certain effect on the dynamic compression modulus of silt sand. The dynamic compression modulus at the same dynamic strain increases firstly and then decreases with increasing the vibration frequency.  The dynamic compression modulus is respectively the largest and the smallest when he phase difference = 0° and = 90°. The vibration frequency has no effect on the dynamic shear damping ratio and the dynamic compression damping ratio of silt sand，but the phase difference has a significant effect on them. When the same shear strain is reached，the dynamic shear damping ratios when = 0° and = 180° basically coincide with each other and are significantly higher than the dynamic shear damping ratio as = 90°. The dynamic compression damping ratio at a phase difference = 90° increases faster after the dynamic strain reaches 0.1%，significantly greater than the damping ratio of other phase differences.

Based on the porous media theory and the continuum mechanics，a fully coupled water-heat-salt-force multi-field model for unsaturated saline soil under temperature gradient is established. The model obeys the conservation laws of mass，energy and momentum of the three-phase system of solid，liquid and gas，takes into account the influences of porosity evolution，water seepage，gas transport，salt desorption-adsorption effect and compressibility of solid particles and pore fluids，and hence，can more accurately describe and explain the heat and mass migration processes and deformation characteristics in unsaturated saline soil. In addition，by selecting the basic unknowns such as porosity，pore water pressure，pore gas pressure，temperature，salt content and displacement，the above multi-field coupling process is simulated by using Comsol Multiphysics software. The mathematical model and simulation results are verified by the experimental results. The results show that the model can well reveal the water and salt migration mechanism and deformation mechanism of unsaturated saline soil under temperature gradient. At the same time，the process of numerical analysis has further deepened the understanding of water and salt migration and deformation processes of saline soil. The study of salt adsorption also provides theoretical preparation for further study of salt expansion of saline soil.

In order to explore the deformation response characteristics of large foundation pit excavation on one side of the comprehensive cross exchange station group，the deformation and mechanical problems caused by the unloading of one side foundation pit with strong proximity to the transfer of three stations in Jincheng square are studied based on the theory of plate and shell，numerical simulation and field measurement. The research results show that the excavation of the strong adjacent foundation pit induces the existing station structure to dump to the unloading side as a whole, and that the lateral deformation of the structure increases exponentially with increasing the excavation depth and parabolically with rising the excavation length. The overall deformation of the station structure increases linearly with increasing the additional load，and the deformation of the top of the structure is more sensitive to the additional load than the maximum deformation position. The deformation of the existing station structure increases linearly with increasing the soil mass density and exponentially with decreasing the station stiffness. Based on Pearson correlation analysis，the excavation depth has a significant impact on the lateral structural deformation of the station，followed by the excavation length， the additional load and the stiffness of the existing station，and the influence of the soil weight is the least significant. Based on the statistical analysis，there are upper and lower limits for the height of the displacement maximum point，and the most dangerous area affected by the excavation of single side foundation pit is 0.59H–0.73H. In the actual construction，attention should be paid to the safety and stability of the retaining structure within the height range.