Elasticity modulus，poisson ratio，uniaxial compressive strength，tensile strength and dynamic stress-strain curves of granite porphyry were obtained under freezing-thawing cycles utilizing the relevant static and dynamic mechanics experiments. On the basis of HJC model parameters analysis，numerical simulations of the SHPB tests were made utilizing LS-DYNA finite element software. According to the results of numerical simulations and experiments，the relationship between the dynamic strength with the strain rate and the freeze-thaw cycles were obtained. The results show that：Shape of the stress-strain curves，the reflected and transmitted waves before and after freeze-thaw is different. Samples have different strain rate with the same incident wave under freeze-thaw cycles. SHPB experiment numerical simulation on the basis of HJC model parameters is reliable. Numerical simulation and laboratory test can complement each other. The dynamic strength is associated with the strain rate and the freeze-thaw cycles，but the influential effects are opposite and interconnected. Study on the dynamic strength of rock under freeze-thaw cycles is the basis of dynamic constitutive relation under freeze-thaw damage and has great significance for analyzing the slope stability of open-pit mining in seasonal frozen region.

Blasting excavation is one of the significant factors which would lead to cracking even instability of jointed rock mass of slope. Based on fracture dynamics mechanics，this paper explores the disturbance of blasting excavation on crack growth in slope rock mass and analyses the effect of in-situ unloading under excavation disturbance and explosion stress wave on stress intensity factor of crack tip and growth mode of cracks. Results show that both of the explosion stress wave and geostatic stress determine the growth mode of cracks in slope rock mass. The growth mode of cracks is mainly I-II compression-shear under in-situ stress. The unloading effect caused by blasting excavation would change the condition of in-situ，which transforms the mode from I-II compression-shear to I-II tensile-shear，therefore increases the risks of crack growth and the cracks become more likely to grow with the rise of unloading degree. The explosion stress wave also increases the risks of crack growth.

According to the reinforcement issue of tunnels which are located in the deep landslide，a kind of self-anchored landside tunnel strengthening structure system is put forward. To the system，only the landslide，which is directly related to the tunnel stability，around the tunnel is taken anti-slide and reinforcement treatment with anti-slide pile and anchor cable，at the same time，strengthening tunnel lining structure. The tunnel lining structure，anti-slide pile and anchor cable form the self-anchored landslide tunnel strengthening structure system. The strengthening structure，which belongs to the statically indeterminate structure，will make slide bed as the stable support point of pile and anchor cable. According to the characteristics of the strengthening structure system，the physical and mechanical model is established，and the matrix transfer method is used to the theoretical derivation，internal forces and displacements of the reinforcement system are obtained.Example analysis results show that as a result of the action of anchor cable，the adverse stress of tunnel wall has been improved，and the anti-slide pile can constraint the deformation of tunnel invert and lining. Accordingly，the stress and deformation of the tunnel lining structure can be optimized and controlled by the anchor cable and anti-slide pile structure.

Coal-bed methane (CBM) is an unconventional gas，its exploitation has fully staffed effect and gets more and more national attention. In order to research the evolution of temperature during gas desorption，the physical simulation of CBM drainage under different gas pressure and in-situ stress was determined based on self-developed multi-field coupling test system for CBM drainage. The results showed as follows：(1) During the drainage process，the coal seam temperature decreased because of gas desorption. As a result，temperature and flow had close correlation，which showed that they decreased rapidly in the early stage，and then declined steadily after a period of drainage. Relationships between temperature dropping and time were logarithmic regression；(2) The closer to the borehole the faster temperature dropped at the same time，the temperature gradient of vertical plane was greater than horizontal plane；(3) The larger the gas pressure，the faster temperature dropped and the greater amount it dropped，while the larger in-situ stress and the slower temperature dropped，the smaller amount it dropped. It can be concluded that the effect of temperature on gas pressure was more significant during gas desorption.

The installation angle of feet-lock pipe has a great influence on the support effect in controlling the subsidence of steel arch. In order to determine the reasonable installation angle，an analytical model of feet-lock pipe and steel arch is established based on a brief analysis of the working mechanism of feet-lock pipe. The theoretical correlation between the installation angle of feet-lock pipe and the vertical displacement of vault is derived using the theory of structural analysis，elastic foundation beam，etc. Then an example analysis is presented in detail to determine the reasonable installation of feet-lock pipe and explain the corresponding mechanism. Analysis indicates that the reasonable installation angle of feet-lock pipe is around 45°. More importantly，this proved to be a general conclusion which is consistent with lots of the experience from construction site. Accordingly，the formulas derived in this paper are proved to be correct. It can provide theoretical support for determining the reasonable installation angle of feet-lock pipe，and the conclusion could be employed in the related design and construction.

To investigate the effect of temperature on the dynamic characteristics of soil，a temperature-controlled cyclic triaxial test system was developed by using combined heating apparatus. The system can precisely realize linear，hierarchical control of sample temperature in the range of 10～100℃. Then，the saturated silt soft clay in Ningbo area is taken for example，and a series of application tests for dynamic characteristics under different temperatures are preliminarily carried out，which validate the effectiveness and reliability of the system. Test results showed that characteristics and development of hysteretic curves under different temperature is consistent with that of general triaxial test system. With the increase of temperature，plastic cumulative strain，dynamic damping ratio and dynamic pore pressure of the soft clay decreased and inversely for dynamic elastic modulus，and the incremental values for above parameters were gradually reduced with the increasing of temperature，from which the hot hardened features is revealed. Furthermore，normalized result of cumulative plastic strain and temperature is exponential.

The study includes an experimental mode constructed based on a real prestressed anchor cable project in the earthquake-stricken zone，where the seismic loading is imposed through low frequency reciprocating loading. The results of the experimental study are summarized. First，the failure of prestressed anchor cables occurs from the upper to the lower part in sequence under reciprocating loading. The top row of cables is the most severely damaged part，where the failure types are dominated by the breakage at the bottom of the cable and the detachment at the head of the cable. No evidence is observed that supports any failure and destruction of bond force and bond stress of the anchoring section. Second，the deformation of cable concentrates on the anchoring section with large strain occurred on the bottom of the section and the part adjacent to the sliding surface. Small strain is found on the free segment. Third，the reciprocating loading imposes greater impact on the prestressed anchor cables in terms of deformation compared to the constant mono-directional thrust or single mono-directional thrust. The reciprocating loading test is the most widely used approach in the experimental study of seismic structural performance，the results obtained in this study provides a mean of systematic evaluation on the safety and quality of prestressed anchor cables during and/or after the earthquake and can be used in comparison with other study on the seismic performance of prestressed cables.

The law of acceleration response can be used to analyse landslide damage mechanisms and determine the earthquake influencing coefficient reasonably. Hence，a centrifuge shaking table model test of colluvial landslide was designed and carried out on a centrifuge shaking table at 50 gravitational accelerations in order to research its acceleration response characteristics. The model landslide was installed into a rigid aluminum alloy container with the length of 600mm，width of 400mm and height of 500mm. Bedrock wave (Qingxi wave) was inputted from the bottom of the model to study the dynamic response behavior of the colluvial landslide under earthquakes of different intensities by scaling the amplitude of the input seismic wave. And the bedrock wave was derived from the one recorded by Qingxi station during the Wenchuan earthquake. Results show that both the horizontal and vertical peak ground acceleration (PGA) amplification coefficients at landslide surface increase with the increasing height of landslide. The landslide shows an obvious elevation amplification effect，i.e.，the increasing rate of PGA amplification coefficients becomes notably larger approaching the slope crest. The acceleration response characteristics of the landslide surface and landslide body are significantly different under earthquake，which shows the surface effect. The horizontal acceleration at bedrock has amplification effect on input seismic wave along the height of the landslide，but it is weaken much weaker by comparison with that at the landslide surface. The slope crest has an obvious wave mode conversion phenomenon to the input seismic wave. The PGA amplification coefficients along landslide surface decrease with the increasing of the earthquake amplitudes. The results are helpful to reveal acceleration response characteristics of the same type of colluvial landslide under earthquake，and provided valuable references for determining the earthquake influence coefficient and analysing landslide damage mechanisms.

In this research，Da Qaidam salt lake region and the surrounding areas was taken as the experimental area. Tension tests of single roots as well as shear strength test of the root-soil composite system of the four dominant halophytes(Leymus secalinus Tzvel.，Leymus paboanus Claus.，Carex enervis C. A. Mey. and Triglochin maritima Linn) were performed. The maximum tensile resistance and the corresponding tensile strength for the 4 species have been determined. In addition，a study on how roots increase the shear strength of soil and the optimal root content through the direct shear test for root-soil composite system for four halophytes was also carried out. The results of single root tensile test shows that the single root tensile resistance for four halophytes is 4.67～10.97 N，the single root tensile strength for four halophytes is 12.32～49.99MPa，meanwhile，the descending order of the tensile strength for the 4 halophytes is Leymus secalinus Tzvel.＞Leymus paboanus Claus.＞Carex enervis C. A. Mey.＞Triglochin maritima Linn.. The direct shear test shows that the cohesion force of the root-soil composite system for the disturbed samples of the four halophytes ranges in 10.44～27.42 kPa and that of soil without root is 8.10 kPa. Compared with soil without roots，the cohesion force of four root-soil composite system increase by 2.34～19.32 kPa and with an increase percentage of 28.89%～238.52%；roots can improve the shear strength of soil and there’s an optimal root content with which the shear strength can reach the peak value，and with the optimal root content，the corresponding cohesion force of the root-soil composite system for the 4 halophytes ranges in 17.94～27.42 kPa and the descending order is Triglochin maritima＞Leymus secalinus＞Leymus paboanus＞Carex enervis. The study has a theoretical and practical significance for Da Qaidam salt lake area and other areas having the similar geological condition in increasing shear strength by roots of halophytes，and meanwhile the study is conducive in the control of geological hazards，like water loss and soil erosion.

Based on the construction of the Xi?an metro tunnel which passes through active ground fissures，it is the first time that the dynamic responses of the horseshoe shape metro tunnel in the seismic loads are studied by the shaking table test. The research focuses on the acceleration，earth pressure and the strain of the tunnel. The test results show that with the dynamic load，uneven settlements and scarps come into being in the seismic load，and the deepest points are along the fissure. The settlement of the hanging wall is larger than that in the footwall. There are cracks of the soil upon the tunnel appear after the seismic loads. The accelerations along the tunnel are similar in every points show that the tunnel is a unity. The acceleration of the hanging wall is larger than that in the footwall；this shows that the hanging wall has the character of expanded the seismic loads. The earth pressure curves show the value and direction changed with the seismic loads，the earth pressure of the middle of the arched is the biggest，the secondary is the points of the bottom of the floor，and the top of the arched is the least one. These findings are of great importance to the rational understanding of earthquake behaviors of metro tunnels through active ground fissure zones，and they may provide earthquake resistant design and construction of practical projects

The coupled thermo-mechanical behavior of saturated clays is summarized，including the temperature effects on volume change，pore pressure，preconsolidation pressure，strength and elastic modulus. Based on the experimental results，a thermal yield surface is introduced to describe the temperature-induced reversible and irreversible volume change of saturated clay. A subloading surface model was extended to consider the temperature effects was established. The extended model can depict the decrease of preconsolidation pressure of overconsolidated clay and the hardening of yield surface by temperature-induced plastic strain. The model was then proved to strictly satisfy the thermodynamic theorems. With the developed model，numerical simulations of drained heating tests，drained and undrained triaxial compression tests of clay with different OCR under different temperature are performed. The simulated results was compared with existing test results，which shows that the model can describe the volume change induced by temperature change，the thermal softening effect on overconsolidated clay and thermal hardening effect of normally consolidated clay.

In traditional ground control theory，supporting action of soft rock under hard roof was often simplified as the Winkler elastic foundation. To accurately analyze the mechanical characteristics and activity of overlying strata，this simplification cannot be contented with the actual requirements. In view of peak of abutment pressure in front of the coal wall，mechanics properties of hard roof model that was thought as soften foundation between coal wall and the peak of abutment pressure and elastic foundation ahead of the peak of abutment pressure were analyzed before the periodic weighting. Methods for determinating peak value of the abutment force were presented. Examples were given to illustrate how to calculate the peak value of the abutment and verify the accuracy using the development approaches. Analysis results were compared with mechanics properties of roof based on full elastic foundation. The research results are shown as follows：Reaction force near the coal wall to the roof obtained by full elastic foundation is 4 times as big as that of the roof calculated by the soften foundation in the depths of 200–300 m. Bending degree of roof，scope of the bend，the distance between peak of bending moment and the coal wall，storage area of strain energy and storage capacity become small near the coal wall，which result from the powerful reaction near coal wall. Reaction near the coal wall to the roof，which is caused by the soften foundation is a fourth as big as that of the former. Owning to the small reaction near coal wall，bending degree of roof and scope of the bend become increase for resisting on overly roof，which lead to the peak of bending moment and the distance between peak of bending moment and the coal wall increase remarkably. Meanwhile，storage area of strain energy and storage capacity outstanding aggrandize in front of coal wall. Then the roof?s deflection increase overall and remarkably when compared with the roof supported by full elastic foundation. Position of peak of bending moment in front of coal wall is related to the location of roof fracture. Position of roof fracture that calculated based on the assumption of soften foundation and elastic foundation is closer to the actual，and the corresponding internal force，strain energy and deflection are closer to the actual when compared to full elastic foundation.

The rheological parameters of Power-law cement grouts are time-dependent，which have an important influence on grouting effects of practical projects. Carrying out theoretical analysis and experimental researches，the rheological equation and seepage motion equation for power-law cement grouts of time-dependent behavior of rheological parameters were established，then column penetration grouting mechanism about them were deduced. At the same time the scope of application，method to determine the parameters and design basis of the side grouting hole in the grouting pipe were analyzed respectively. Then they were validated by means of designing indoor grouting experiments. Experiment results show that equivalent transverse diffusion radius of actual measurement values in the indoor grouting experiments have about 20%-30% differences with that of theoretical values calculated by column penetration grouting mechanism based on Power-law cement grouts of time-dependent behavior of rheological parameters，but they are all within the acceptable error limits. Because the international and domestic researches on column penetration grouting mechanism based on Power-law cement grouts of time-dependent behavior of rheological parameters were seldom reported，therefore，research achievements may not only can play a reference guiding role for the theoretical research，design and construction on grouting technique，but also may provide strong theoretical basis for perfecting the penetration grouting mechanism.

Considering the shortages of late time apparent resistivity interpretation of vertical component in Transient Electromagnetic Method (TEM) advanced prediction at present，this paper discusses full space and full zone apparent resistivity method of arbitrary coplane vertical magnetic component in tunnels. First，calculate the full space vertical response of loop source from response in homogeneous full space of electrical dipole and vector addition. Then，deduce the full zone apparent resistivity definition of TEM coplane vertical magnetic field from full space time domain response. Lastly，analyze the influence of tunnel cavity and aquifer structure. By comparing the method in this paper with traditional method，the results show that our method can effectively avoid the influence of tunnel cavity and is better in aquifer structure detection.

Focused on the current situation of the underground caverns and the key difficult problem of the information construction, a new method is put forward for the rapid analysis of the stress field of surrounding rock, which is based on the quantitative laws of the results of numerical tests under the main influence factors of the surrounding rock. Firstly, eight main influences of the stress field of the surrounding rock without fault were pointed out which is based on the systems numerical testing. Then, a Fast Analysis System for the Tunnels(FAST) without fault is build which is based upon lots of numerical test results，measured data, expertise and the powerful artificial neural network method. Further more, the FAST with one fault or two were established separately, which is benefited from the influence coefficient of deformation from fault that was introduced by our research group years ago and greatly reduce the number of the numerical experiments. After comprehension of these three FASTs and the fast inverse analysis system and the fast evaluation system, a fast intellectual analysis and evaluation system is established based on the mixed programming techniques of VB and FORTRAN. Several practical engineering applications have showed a good reliability and applicability of the system.

In order to calculate the storage capacity in void ofcaving rock in the goaf，the fractal theory was introduced to research the related parameters of storage void in the goaf of Yushenfu coalfields in North Shanxi. Based on the measurement data of fractal dimension from caving rock void in the goaf，the model for void structure of caving rock in the goaf was set up by Menger sponge fractal model. The void ratio and residual expandition coefficient formulas of caving rock in the goaf were deduced，then the storage capacity in void of caving rock in the goaf was calculated. The 32301working face in Shennan coal field was taken as engineer background to study the fractal calculation and application of water storage in void of caving rock in the goaf. The results showed that：the fractal dimension of caving rock void in the goaf was 2.93，the storage performance was good. And the largest storage capacity was 3848231.93m3 calculated by fractal method，it was consistent with the actual storage capacity in the field. Using fractal method to calculate the storage capacity of void of caving rock in the goaf was feasible，it has important practical significance for using limited water resources effectively in arid and semi-arid mining areas.

According to soil arching effect，stresses on the wall and sliding plane of the sliding backfill mass at arbitrary depth is obtained. And the pseudo-static method and total force equilibrium，a new formula of the seismic active failure angle behind non-vertical rigid retaining wall is obtained under translation mode. Then according to differential level layer method，by force and moment equilibrium，new formulae of the seismic active earth pressure against non-vertical rigid retaining wall and its coefficient are putted forward under translation mode. And those of the seismic active earth force，its coefficient and the application height are also derived. The distribution of seismic active earth pressure by proposed formula is non-linear along the height of wall. In addition，The influences of on the wall-back inclination，internal friction angle of backfill，wall-soil friction angle，seismic coefficient and load against the backfill surface on the seismic failure angle，seismic active earth pressure and its coefficient，seismic active earth force and height of its application are investigated.

The calibration test had been carried out to improve the accuracy of Time Domain Reflectometry (TDR) sensor measurements. The effect of dry density，structure properties and soil texture on soil-water content measured with the TDR sensor is explored，and the related mathematic correction models are established，on the basis of the comparative analysis of soil-water content of Q3 loess and paleosol measured by TDR sensor and oven-drying method. The test results indicate that，the use of the factory-supplied parameters resulted in overestimation of soil-water content compared to the oven-drying soil-water content，and the effect of dry density variation on the sensor measurements should not be neglected；The correction model of TDR sensor soil-water contents is established by considering the effect of dry density. It is proved that the correcting results of using the correction model is superior to the cubic fitting equation of regression analysis between θv and θw determined in the laboratory，and when the volumetric water content range is from 9.2% to 39.9%，the adjusted soil-water content is within 2%，and within 3% when the volumetric water content range is from 39.9% to 46.3%. No statistically significant difference of soil-water contents was observed between the undisturbed and the remoulded samples，and therefore the calibration test in laborary can substitute for in situ test；there are notable differences between loess and paleosol in soil texture and therefore the calibration model should be established respectively.

The underground railway coupling analysis model was established and used to study the dynamic response of track systems and saturated soil. The model was divided into four parts，the moving train，floating-slab tracks，liner and saturated ground. The train load was simulated by a series of moving constant or harmonic load in accordance with the geometry of a real train. The tracks consisted of an upper Euler-Bernoulli beam to account for the rails and a lower Euler-Bernoulli beam to account for the slab. By adopting the method of 2.5D FEM，the elastic theory and the Biot’s theory were used to simulate the liner and saturated porous medium respectively. The floating-slab tracks and soil medium were coupled by the boundary conditions at the tunnel invert. The three-dimensional time-space domain dynamic response was obtained from the fast inverse Fourier transform (IFFT). Computed results show that with increasing train velocity and self-vibration frequency of the moving harmonic load，the dynamic responses of the ground surface increase obviously. The maximum ground surface responses generated by the moving constant load are located directly over the tunnel centerline with a constant space attenuation rate. The dynamic responses of ground surface induced by moving harmonic load are larger than those induced by moving constant load and become the strongest at certain distances from the tunnel centerline. The distribution of velocity spectrum for the rail and ground surface is centered on self-vibration frequency of the harmonic load.

To study the change laws of clay pore and mechanical parameters under different temperature effect，this paper，taking the different-temperature roasted clay as the research object，mainly analyzed the law of porosity，permeability，fractal dimension of pore volume，uniaxial compressive strength and Protodyakonov scale of hardness by using the mercury injection method and uniaxial compression test. The findings were as follows：The pore in samples was dominated by the open pore，and the connection among pores was well. The main pore size ranged from 500 nm to 1 000 nm. Within the temperature range tested，the total volume of macropores increased with the temperature rising，the total volume of micropores increased between 100 ℃～650 ℃ but decreased over 650 ℃ as the temperature rose；Porosity increased between 100 ℃～700 ℃ but had a slightly decline over 700 ℃ with the increase of temperature；the fractal dimension of pore volume，by means of Menger fractal sponge and thermodynamic model，in general increased with the temperature rising，and the pore characteristics of samples could be represented better by the fractal dimension of pore volume through thermodynamics；with increasing temperature，the permeability increased when the temperature ranged from 100 ℃ to 700 ℃ and slightly decreased when the temperature exceeded 700 ℃；as the temperature rose，uniaxial compressive strength and Protodyakonov scale of hardness remained constant basically between 100 ℃～400 ℃，increased rapidly between 400 ℃～700 ℃ and decreased over 700℃，which was closely related to the transformation of minerals inside samples.

In order to study the relationship between acoustic characters of frozen silty clay and its physics mechanics properties，ultrasonic tests of frozen silty clay were conducted，and measured its tensile and compressive strength under various negative temperatures. The influence of temperature，water content and dry density on ultrasonic wave velocity and the relationship between wave velocity and strength of frozen silty clay were analyzed base on the tests. Test and analysis results indicated that，ultrasonic wave velocity rapidly changes in the temperature range of -1℃ to -7℃. There exists critical water content and the value is 16.03%. Ultrasonic wave velocity increases firstly and then decreases with an increase of water content. Under the same water content，wave velocity increases linearly with an increase of dry density. Three dynamic elastic mechanical parameters of frozen silty clay were obtained from the measured wave velocities and specimen densities based on elastic theory and its change trends with temperature was analyzed. There exist good correlations between ultrasonic wave velocity and strength of frozen silty clay. The larger the strength and the faster the wave will be. It is found that the ultrasonic test technique can be used to test frozen soils nondestructively and lay the foundation for the prediction of frozen soil strength.

In order to obtain a wealth of SEM image information for soil microstructure research，a larger number of SEM images for soft soil in Zijingang Hangzhou had been scanned. Three-dimensional calculation model was built by analyzing the characteristics of soft soil SEM image. First proposed the method of the use of Image-Pro Plus (IPP) to calculate soft soil three-dimensional porosity，the influences of calculated step size，magnification，threshold size and analysis area size on calculated results were studied. The results show that，calculation accuracy relates to step size，smaller step size is corresponding to a higher accuracy，and step size 2 can both satisfied the computing capacity and accuracy requirements. it is suitable to choose a magnification of 1200±300 times to calculate three-dimensional porosity. Threshold value size relates to magnification times，greater magnification should be increased threshold value accordingly. Area of analysis can not be too small，only by choosing over 70% of the total area of the image can effectively reflect the entire information of the image.

The visual model test and distinct element method are employed to study the pile-soil force transmission characteristics，soil progressive deformation around pile，and failure behavior of cast-in-place concrete pipe pile(PCC pile). The study results show that the load-settlement curve of PCC pile varies gradually，outside shaft resistance is higher than inside，inside shaft resistance development lags behind outside. Outside shaft resistance plays more fully on upper part of pile，inside shaft resistance plays more fully on lower part of pile，inside shaft resistance and tip resistance controls later bearing capacity of PCC pile. Soil outside the pile presents inclined downward shear deformation，influence scope is cylindrical with a radius of 2D. Soil inside pile is given with the vertical deformation，and kept the step with pile at the beginning of loading，the inside relative displacement of pile and soil at the bottom of pile is bigger than upper soil during the later stage of loading. Pile tip soil can be divided into conical vertical compression area and lateral deformation area，and the influence depth is 4D，deformation pattern presents fan-shaped in the plane. The distribution of pile contact force chain brings into correspondence with shaft resistance distribution characteristics along pile length，soil porosity changes under pile tip reveal the shaft resistance plays before tip resistance from mesoscopic angle. Research results are important for further understand the interaction between PCC pile and soil.