With the development of tunnel engineering in the direction of “deep，large and long”，high geotemperature has become one of the inevitable geological disasters in tunnels. This paper summarizes the literature from three aspects：the disaster forms，classification standards and disaster control technology of high geotemperature tunnels. The disasters caused by high geotemperature mainly include high-temperature and high-humidity environments，deformation and failure of tunnel surrounding rock，and failure of the supporting structure. The existing classification standards of heat-hazard in underground engineering are mainly based on the surrounding rock temperature and the ambient temperature in the tunnel，focusing on the impact of thermal environment caused by high geotemperature on the health of workers，while ignoring the influence of high geotemperature on surrounding rock and supporting structures. Meanwhile，high temperature water gushing is not considered. The control technology of high-temperature and high-humidity environment includes non-artificial cooling technology and artificial cooling technology. Exploring the form，technology and material of supporting structure suitable for high temperature environment is the main way to control the deformation and destruction of surrounding rock and prevent the failure of supporting structure. Southwest area is an important area facing high geotemperature disasters in China，with disaster characteristics such as ultra-high rock temperature，high-temperature water gushing，ultra-long-distance ventilation and plateau cold climate. Based on the consideration of the types of disasters induced by high geotemperature，the classification criteria of heat-hazard of high geotemperature tunnels are explored，which are based on dry heat type and hydrothermal type. On this basis，combined with the principle of “prescribing the right remedy to the case，classified control”，the disaster countermeasures of extremely high geotemperature tunnel of southwest area are explored.

In order to study the multi-source information response of force，electromagnetics and acoustics in the whole process of deformation and fracture evolution of structural surrounding rock，and to explore the internal relation between deformation evolution process and surrounding rock disaster under the interaction between the rock-base block and the structural interface，the mining coal roadway of a coal mine in Shandong was used as engineering background to conduct the study. The large-scale physical model tests on the structural surrounding rocks under different support strengths were carried out to investigate their whole loading processes by relying the self-developed roadway surrounding rock model test system，combined with multi-source information monitoring such as internal stress，surface displacement，electromagnetic radiation，resistivity，ultrasonic，borehole peeping internal cracks and 3D tomography. The results show that the surrounding rock without support presents brittle failure characteristics relating to the shear slip of the structural plane during the bearing process. In contrast，the bolt and cable support has greatly strengthened the peak strength and peak strain of the model by restraining the shear slip of structural plane and the displacement deflection of structure，with a difference of nearly one time in value，and effectively weakened the stress drop before the peak of the model. The internal stress of the structural surrounding rock without support directly decays with loading，and its displacement field has obvious block structure deformation characteristics. While the supported structural surrounding rock shows more obvious pressure arch effect，and the block structure deformation characteristics gradually weaken with the increase of support strength. Compared with the structure without support，the electromagnetic radiation intensity of the surrounding rock of the supporting structure is higher，and the electromagnetic radiation pulse fluctuation is more significant. This is due to the transformation of the shear slip of rock foundation along the structural plane under the condition without support to the crushing deformation of anchored rock foundation block under the condition with support，which restrains the large structural deformation induced by the sliding of block rock foundation along the structural plane. By using the apparent resistivity to quantitatively evaluate the damage degree of the surrounding rock，the high resistance area of the structural surrounding rock without support accounts for 18.46% of the model，while that with bolt and cable support only accounts for 9.94% of the model，which is basically consistent with the loose circle of surrounding rock obtained from ultrasonic velocity feedback. With the increase of support strength，the crack development of surrounding rock and the roof delamination significantly decreases. Its instability and failure are attributed to the deterioration of surface protection of the shallow anchoring structure and the dislocation and slip of the deep structure.

Drill-and-blast tunnel method and TBM tunnelling are commonly used in divisional excavation when a tunnel passes through rock and soil strata. A transition tunnel is generally built to connect the drill-and-blast tunnel and the TBM tunnel. As a result，the stiffness of the tunnel changes suddenly due to different cross sections and types. The transition tunnel becomes precarious under earthquake loadings，which should be paid significant attentions in seismic design. Regarding to the anti-earthquake issue of the tunnel passing through the rock-soil strata in seismically active areas，a shaking table test is carried out to study the seismic response of the transition tunnel under strong earthquake loadings. Accelerations at different tunnel portions，pressures between rock and lining，and joint extensions of the TBM tunnel are analysed based on the shaking table test. Furthermore，the influence of the stiffness change on the dynamic response of tunnel is discussed. Results show that the acceleration amplification factor of tunnel decreases with the increase of input ground motion intensity. The tunnel with larger stiffness leads to larger amplification factors. The rock-lining pressure increases with the increase of earthquake intensity；while the pressure shows a slow increase when the PGA reaches to 0.5 g. It is speculated that tunnel structure and rock show regional damages. Also，higher earthquake intensity shows larger joints extensions of shield tunnel. It is noted that the joint extension close to the inner lining is five times to the extension at normal area due to the sudden change of stiffness at the inner lining area. The research is able to provide guidance for the seismic design of the transition tunnel with changing stiffness.

Constructing three-dimensional discrete fracture network(DFN) is a commonly-used method to simulate the random distribution of discontinuities in the rock masses for jointed rock slopes. To overcome the shortcomings of traditional Baecher disc and polygon models in constructing three-dimensional DFN model of a slope，in this paper，a method for generating an universal elliptical disc(UED) model-based DFN in 3DEC software is proposed. Based on this，the stability of a jointed rock slope can be accurately and efficiently evaluated. At the same time，the basic principles of the UED model are briefly introduced，including planarization of polygon fractures，optimal elliptic disc model fitting and generation of spatial elliptical disc model，etc. The procedure of constructing the DFN model of jointed rock slopes based on the UED model in 3DEC software is presented. Finally，taking an open pit mine slope as the example，the influences of characteristic parameters(ratio of long axis to short axis and rotation angle) of elliptic disc model for discontinuity groups on slope stability are investigated，and the differences between the UED model and traditional Baecher disc model are compared. The results show that the proposed method can avoid tedious programming using fish language and inefficient internal modeling of 3DEC software，and quickly construct the three-dimensional DFN based on the UED model and conduct slope stability analysis in 3DEC software. It thereby provides an important technical means for efficiently evaluating the stability of three-dimensional complex jointed rock slopes. Additionally，the influences of the characteristic parameters of UED model on the slope stability are addressed. It is confirmed that it is of great necessity to construct the DFN of slope by using the UED model in engineering practice.

The movement process of high-position and long-runout landslides is complex and the sliding main body is changeable. The dynamics theory of post-failure and inversion prediction technology have always been the focus and difficult problems in the field of disaster prevention and reduction. In this paper，the dynamic process of polymorphic transformation based on the degree of density in the movement of high-position and long-runout landslide is revealed by survey analysis，theoretical research and numerical technology development. Based on SPH and DEM algorithm and dynamical constitutive model transformation，a new numerical simulation method for landslide post-failure motion(LPF3D) is presented. The results show that：(1) Through the analysis of actual landslide video and grains chute experiment recording，it is found steric effect which the grains motion in the process of landslide movement mainly present the dense state，dilute state and ultra-dilute state，and the grains state changes and transforms with each other at all times. (2) The volume fraction is used as the criterion of discrete grains number and grains state transformation，and the numerical calculation method and critical volume fraction is proposed to solve different states in landslide movement based on different dynamical constitutive models. (3) The macroscopic continuum algorithm based on the theory of polymorphic transformation is used in the inversion of the debris flow of Jiweishan landslide in Wulong，Chongqing，and the simulation results are basically consistent with the actual landslide accumulation. (4) The LPF3D simulation method achieved the transformation of grains state and the efficient calculation of the actual number of grains in the calculation of landslide failure movement，and improves the convergence stability of the calculation，which has great computational advantages. Based on the above research，it is believed that in the risk investigation and dynamic process analysis of high-position and long-runout landslide flow，the influence of the state changes of sliding body grains and the actual number of grains should be fully considered. The LPF3D simulation method provides an efficient，quantitative and optional method for the risk assessment and prediction of high-position and long-runout landslide.

In order to reveal the influence mechanism of soft interlayer characteristics of coal-rock on ultra-low friction impact ground pressure，the self-made coal-rock interface ultra-low friction test device was adopted，and the coal particles，sandstone particles and coal sand grains were laid at the coal-rock interface by changing the soft interlayer medium，thickness and particle size，and the coal block was used as the working block to characterize the ultra-low friction effect strength by using its horizontal displacement. The influence of different soft interlayer characteristics at the coal-rock interface on the ultra-low friction effect of the coal-rock block was tested. The results of the study show that the vertical disturbance amplitude increases linearly with the strength of ultra-low friction effect. There is a significant influence zone in the relationship between vertical disturbance frequency and ultra-low friction effect influencing. When there is no soft interlayer at the coal rock interface，there is a significant influence zone when the vertical disturbance frequency is 1–4 Hz. When the coal-rock interface contains a soft interlayer，there is a significant influence zone when the vertical disturbance frequency is 1–6 Hz. The coal-rock interface within the significant influence area is more prone to ultra-low friction effect. When the vertical impact disturbance frequency and amplitude are fixed，the ultra-low friction effect occurs at the interface of the coal rock containing the soft sandwich layer，and the strength is 2.25 times and 8.84 times that of the interface of dry friction and cemented coal rock，respectively. When the coal-rock interface contains coal particles，sand grains and soft interlayers of coal sand grains，the average increases of ultra-low friction effect intensity with the increase of disturbance amplitude are 33.5%，57.1% and 42.4%，respectively. The coal rock interface contains a soft interlayer，the larger the thickness of the sandwich(5 mm)，the smaller the particle size(20–35 mesh)，the more prone to ultra-low friction effect at the coal rock interface. Combined with the case analysis of ultra-low friction impact ground pressure accident of Hongyang Three Mines，it is shown that the interface of coal rock with soft sandwich is more prone to coal body instability，thereby inducing ultra-low friction impact ground pressure.

To investigate the influence of the roughness of the interface on the progressive failure characteristics of tunnel-type anchorage(TTA) in soft rock，three similar models of TTAs with different interface roughnesses were made，and the digital image correlation technology was employed simultaneously to systematically compare and analyse the propagation and spatial distribution characteristics of cracks during progressive failure of TTAs. The results indicate that the ultimate bearing capacity of the TTA decreases gradually with the decrease of the roughness of the interface. Furthermore，the initiation angle of the crack in the surrounding rock increases gradually with the decrease of the roughness of the interface. Simultaneously，the initiation location of the main crack in the surrounding rock of the upper part of the plug body also gradually moves to the middle and front end of the crown of the plug body. The surrounding rock in the upper part of the plug body changed from the overall failure to the local failure. The failure range of surrounding rock is concentrated in the middle and front part of the crown. The cracks near the floor of the plug body gradually change from shear cracks into sporadic large-angle short cracks. The shear cracks are approximately parallel to the axis of the plug body and penetrate to the ground surface. The failure mode of the lower part of the plug body changed from a thin shear zone to slip along the interface. With the decrease of interface roughness，the failure sequence of the TTA changes from “compressive-shear(or tensile-shear) failure of rock mass at the back end of the crown→slip and debonding of interface→tensile-shear and tensile failure of rock mass at the middle front end of the crown” to “slip and debonding of interface→tensile-shear failure of rock mass at the front end of the crown→tensile failure of rock mass at the back end of the crown”. The research results can provide a basis for revealing the working characteristics and failure mechanism of TTAs and improving the design calculation theory.

The splitting failure of high sidewall caverns has become an important factor affecting the construction and excavation safety of the underground powerhouse of large hydropower stations. In order to clarify the formation mechanism of this phenomenon，taking the high sidewall cavern of the main powerhouse of Pubugou Hydropower Station as a case study，the true 3D geomechanical model test of excavation and unloading of high sidewall cavern under high in-suit stress is carried out，and the nonlinear deformation characteristics and splitting failure law of excavation and unloading of high sidewall cavern are revealed. On the basis of the model test，an elastic-plastic damage-softening model of splitting failure of underground cavern based on strain gradient and the failure criterion of splitting failure are established. Based on this，the calculation and analysis program of underground cavern splitting failure is developed based on ABAQUS software. Through the numerical simulation of multiple working conditions，the generation conditions and formation mechanism of splitting failure of high sidewall cavern are effectively revealed：the important condition of splitting failure is that the initial maximum principal stress is parallel to the direction of tunnel axis and the value reaches a certain degree. In the process of excavation and unloading，the oscillating change of the stress of the high sidewall is the fundamental mechanical cause of splitting failure. The research results provide an important experimental and theoretical basis for the prevention and control of splitting failure of high sidewall caverns.

To study the damage law of rock under dynamic and static superimposed loads，a rock mechanics experimental system with multi strain rate dynamic and static superposition was developed. The experimental system includes assembly reaction unit，dynamic and static superposition unit，creep loading unit and intelligent control unit. The four units have the characteristics of assembly with high rigidity，multi strain rate dynamic and static load superposition and simulation of elastic strain energy release，automatic balance creep loading，multi-element information acquisition and automatic high-frequency capture of sudden change information，respectively. Finally，various types of dynamic and static loads with different strain rates，such as creep(＜10－4 s－1) and static load (10－4–10－2 s－1)，static load and pulse load(10－2–100 s－1)，static load and impact load(100–102 s－1)，static load and cyclic impact load，can be applied on a single rock surface. Using the experimental system，the marble damage and failure experiments under the dynamic and static superposition were carried out，and the damage evolution law quantitatively characterized by the peak strength and cumulative residual strain. The experimental results showed that the creep，static load + pulse，static load + impact have obvious damage effects on rocks，the damage effects from strong to weak are: static load + pulse，static load + impact，creep. At the moment of dynamic and static superposition，the strain increases abruptly，when the dynamic load is significantly smaller than the static load，the dynamic load mainly produces elastic strain. When the dynamic load is the same，the damage increases rapidly with the static load increasing；when the static load is the same，the damage decreases with the increase of the dynamic load strain rate，which has a significant strain rate effect. In the process of static load + cyclic impact，the specimen damage presents an S-shaped evolution trend of “rapid growth→gentle development→rapid rise”.

Cataclastic rocks are a special kind of weak rock mass developed in a strong tectonic zone，whose engineering mechanical properties are greatly influenced by disturbance or weak constraint. However，it is difficult to obtain undisturbed specimens of cataclastic rocks and to accurately measure its mechanical properties in the laboratory. Therefore，the confined compression test of undisturbed specimens which are obtained by investigating the in-situ undisturbed sampling devices and methods is done. The calculation model is established on the assumption of the linear axial shear stress along cylinder. Subsequently，the analytical solutions of deformation parameters under high stress by confined compression are derived. Moreover，the confined compression numerical test and the in-situ bearing plate test are conducted. The results show that：The variation range of acoustic velocity between specimens and sampling points is less than 5%，thus indicating that specimens obtained by steel cylinder devices with blades can basically keep their original structure characteristics. The average differences between calculated values and measured values of axial strain at different heights do not exceed 6.43%，which verifies the rationality of the distribution assumption of axial shear stress in the calculation model. The ratio of in-situ deformation modulus to analytical compression modulus are 0.17 and 0.36 respectively，when the rock pressure are less than and greater than 15.80 MPa. The average differences of comprehensive compression modulus and Poisson?s ratio between the analytical calculation and the numerical solution are 5.68% and 4.18% respectively，which verifies the reliability of the analytical calculation method for the compression deformation response. The research results can provide an effective method for testing the mechanical properties of cataclastic rocks，thus creating theoretical and practical values for the engineering construction of similar areas.

In order to explore the fractal characteristics of fracture toughness and crack propagation of saturated tuff under impact loads，the 50 mm diameter split Hopkinson pressure bar(SHPB) was used to carry out type I dynamic fracture toughness tests on dry and saturated straight channel semicircular bending tuff specimens(NSCB) under different impact pressures. The crack propagation process of the specimen was acquired by a high-speed camera，and the crack propagation trend and the micro structure of the fracture were analyzed by Image J software and electronic digital microscope. The results show that there is a linear positive correlation between the fracture toughness of the specimen and the loading rate. When the impact pressure is 0.2，0.3and 0.4 MPa，the average fracture toughness of the dry specimen is 1.08，1.10 and 1.10 times that of the saturated specimen. Water saturation reduces the ability of the specimen to resist crack propagation，and the fracture toughness decreases accordingly. Under the impact load，the crack propagation speed of the specimen increases first and then decreases rapidly to a stable development. The crack propagation length and opening width increase continuously with the increase of time. Water saturation can promote the crack growth and opening of the tuff samples. With the increase of the impact air pressure，the fractal dimension of the specimen increases. The mean fractal dimension of the water-saturated specimens at 0.2，0.3 and 0.4 MPa is 1.08，1.14 and 1.13 times that of the dry specimens. The saturated water effect increases the complexity of crack propagation in the specimens. Under the action of impact load，the crack propagates along the structural weak surface of the specimen，and the arbitrary distribution of the structural weak surface causes the crack propagation to produce a bending effect. The softening effect of water aggravated the bending degree of the specimen during crack propagation.

When disturbed by blast impacts，the high-stress deep surrounding rock joints tend to induce instability failure. To investigate the disturbance shear instability characteristics of rock joints in the neighborhood of strength limit，a series of disturbance shear tests under different initial stresses，disturbance peaks and disturbance frequencies were carried out on symmetrical regular dentate rock joints. The deformation and energy evolution laws of rock joints in the process of disturbance instability were also analyzed. Test results show that the disturbance instability displacement of same rock joints is close to that under quasi-static loading and the cumulative curve of irreversible deformation presents in three stages. Instability displacement of rock joints is controlled by the initial stress state，and the instability is more likely to occur under high initial stress，high disturbance peak and low disturbance frequency. The loading energy and unloading recoverable energy show the “two-way deviation” feature during the deformation process.

Taking the Dongmachang No.1 tunnel of Huali Railway as the background，the short-term creep characteristics and creep parameters of muddy siltstone were analyzed by the uniaxial compression creep test and field monitoring，and the mechanical behavior of tunnel construction considering the coupling effect of short-term creep effect of surrounding rock and construction disturbance was explored. Then，the influence and the sensitivity of the mid-step length，the second layer of initial support installation timing as well as the initial support closure time on the tunnel support effects were analyzed. The results show that when the short-term creep effect of the surrounding rock is not taken into account，the displacement of the arch base is reduced by 27.03% and the area of the plastic zone is reduced by 16.91% in the calculation results. Different construction parameters have different effects on deformation control of each part of the tunnel. Changing the length of the mid-step and the timing of second layer initial support installation may efficiently distribute the support force of the first and second layers of the initial support；the earlier the initial support closure，the better the state of force in the tunnel. Sensitivity analysis results：mid-step length＞second layer of initial support installation timing＞initial support closure time. Construction control can be carried out according to the principle of “step growth，fast support and fast sealing; step shortening，slow support and slow sealing”.

To study the effect of flaw inclination angle on strain evolution and failure behavior of flawed rocks，a set of compressive-shear tests were conducted with red sandstones containing a single pre-existing flaw. The full-field strain evolution of flawed specimen was monitored，recorded and analyzed using digital image correlation (DIC) technique，a criterion was proposed to determine initiation position of wing crack under compressive-shear loading，and the fractography of rock fractures were examined using scanning electron microscope(SEM). The results show that the degree of deterioration of the peak compression-shear force on the specimen by pre-existing flaw depends on its flaw inclination angle，and the strain evolution processes of the flawed-specimens can be divided into four typical stages，including compaction stage，quasi-elastic stage，crack propagation and coalescence stage，and the post-peak stage. Based on the crack initiation locations，five typical strain concentration zones were summarized，including strain bands of wing crack，anti-wing crack，secondary crack，normal and tangential edge cracks，respectively. The DIC analysis of strain evolution at several key points of some typical specimens shows that the initiation and propagation of cracks were dominated by a mixed tension-shearing effect. A novel crack dominate parameter(CDP) was proposed to quantify the degree of tension and shearing effects on crack initiation mechanism. The results show that with increase of flaw inclination angle，the shearing effect on crack initiation mechanism of the anti-wing crack gradually decreases，while its effect on secondary crack increases. When the flaw inclination angle over 30°，the mixed tension-shearing effect gradually dominates the initiation mechanism of wing cracks. Based on circular maximum theory，a theoretical criterion was proposed to determine the initiation position of wing cracks under compressive-shear loading，and the theoretical predictions agree well with the experimental results. The SEM analysis of some typical fracture surfaces shows that the fractography of wing cracks changed from rough to relatively smooth when the flaw inclination angle increased from 0° to 30°，indicating enhancement of the tensile extent，while the fractography of anti-wing cracks，secondary cracks and edge cracks were presented in layered，parallel and strip forms，respectively. The findings of this study could facilitate understanding of cracking behavior of fractured rock mass subjected to compressive-shear loading.

Geomaterials can exhibit dilatancy and softening behavior in engineering practice. When simulating the strain-softening characteristics as well as the accompanied shear bands with the standard finite element(FE) method，the predicted results suffer from strong mesh dependency，which greatly affects the accuracy of the results and may even result in convergence difficulties. In this paper，a novel FE algorithm of nonlocal strain regularisation is proposed based on the critical state theory for soils. Compared to the conventional constitutive integration scheme used in a FE analysis，the proposed algorithm in this study is capable of effectively solving the mesh dependency and convergence problem when modelling the strain-softening behaviour of geomaterials. Meanwhile，the presented algorithm can adequately incorporate the nonlocal strains into the integration process ensuring its application to all critical state type models such as the modified Cam-clay model. The implementation procedures of the proposed method in a finite element program were explained in detail by taking the unified hardening model for clay and sand(CSUH) as an example. The effectiveness of the method was subsequently verified through a series of numerical analyses of biaxial compression tests. The numerical results become almost unchanged with the mesh discretization once the adopted mesh is sufficiently fine，while the associated iterative process exhibits robust performance.

Instability and even collapse of slurry trench may occur during the excavation of diaphragm wall in saturated sand. At present，there are few analyses on the slurry infiltration and the stability of slurry trench in sand. Based on the mechanism of slurry penetration and diffusion，a model for slurry infiltration in sand is established to consider the coupling relationship among the degree of slurry infiltration，velocity variation and soil pore change. The model parameters are calibrated by comparing with the existing tests. Plane-strain models are further established to simulate the slurry infiltration after the trench excavation. The influences of slurry specific gravity and sand pore on the quality of mud cake and the infiltration range of slurry are then discussed. The influences of slurry density and soil porosity on the trench stability under slurry infiltration in sand are further analyzed by strength reduction method. It shows that a proper increase in slurry concentration is beneficial for the trench stability in loose sand. Finally，the method is applied to a practical engineering for further verification.

Highly water-rich sand strata is prone to causing seepage failure and is the main risk source for underground construction. At present，the mechanism of seepage failure in the composite strata of“upper fine and lower coarse”is not clear. By analyzing and comparing 14 groups of sand erosion model test data，it is found that the seepage damage characteristics of the composite strata composed of the lower coarse sand and the upper fine sand are significantly different from that of the single strata. The lower layer has small energy consumption and mainly plays the role of water supply，while the upper layer of fine sand has small permeability and bears most of the seepage force，thus causing rapid loss of fine sand particles and leading to sand boiling/static liquefaction. Under the same boundary conditions，groundwater disturbs the soil of the composite strata more extensively，and the soil loss is more significant and the loss rate is faster. The sand boiling phenomenon is most significant when the seepage outlet is close to the interface of coarse sand and fine sand and on the side of fine sand. Based on the observations obtained from the test，the causes of the large area collapse in the “2.7” subway accident in Foshan in 2018 were discussed. It is considered that the composite sand layer of “fine top and coarse bottom" and the unique location of the leakage outlet - "the interface of fine sand and medium coarse sand” are the main causes of the large area collapse of the accident. In similar projects，it is necessary to pay attention to the identification of the composite sand layer and make good sealing measures to prevent the emergence of the seepage outlet.

To investigate the anisotropy and stress directional mechanical behavior of geotechnical materials，directional shear tests of aeolian soil with principal stress direction angles of 0°，15°，22.5°，30°，45°，60°，67.5°，75°，and 90° were performed using a hollow cylinder torsion shear apparatus(GDS-SSHCA). The variation law of the shear stress-shear strain curve and anisotropic strength characteristics of aeolian soil under the action of different major principal stress directions are presented. Test results shown that when ?≤30°，the shear strength of soil increases with the increase of ?；when ?＞30°，the shear strength of soil decreases with the increase of ?. Significant anisotropy exists in the strength of aeolian soil samples under directional shearing in different major principal stress directions. Based on the test results，the equivalent modified anisotropic Lade-Duncan criterion (EL-D criterion ) of aeolian soil is established by using the fabric-stress coordinate transformation based on the idea of equivalent stress and considering the stress，the size of the fabric，and the direct relationship between the stress and the fabric. The reliability of the established anisotropic criterion is verified by the directional shear test results of aeolian soil. The results show that EL-D criterion established in this paper can better describe the strength characteristics of stress-induced anisotropy in aeolian soil. The research results will provide scientific support for the study of anisotropy of geotechnical materials and the prevention and control of aeolian soil engineering disasters.

As a method to determine the maximum dry density of coarse-grained soil filler on high-speed railway subgrade，vibration compaction test lacked the standardized research on test parameters. In order to put forward the vibration compaction standard and test method of high-speed railway coarse-grained soil filler，the vibration compaction test was carried out by self-developed large intelligent vibration compaction instrument. The influence of test parameters(water content，size and vibration parameters) on dry density was further analyzed，the standardization mechanism of vibration compaction test parameters was revealed，and the determination method of vibration compaction test parameters under resonance was further proposed. Finally，the rationality of the method was verified according to the field rolling compaction test. The research results show that：(1) With the increase of water content，the dry density of vibration compaction method decreases first and then increases. However，when the water content is too high，the phenomenon of "mud pumping" appears in the vibration compaction test. With the critical water content after drying，there is no phenomenon of "mud pumping " in the compaction，and the dry density meets the on-site rolling compaction standards.(2) Taking 3.9 as the diameter-diameter ratio(the ratio of the inner diameter of the compaction cylinder   to the maximum particle size of the filler  ) and 3.5 as the thickness-diameter ratio(the ratio of the paving thickness   to the maximum particle size of the filler  ) of the vibration compaction test can eliminate the influence of the boundary size effect of the compaction cylinder on the dry density. (3) The mathematical model of the relationship between filler gradation and natural frequency is established. In the test，the vibration frequency is set as the natural frequency of filler，and the vibratory quality is set as 600 kg. Moreover，when the ratio of excitation force to vibratory quality is controlled to 1.8 by adjusting the eccentricity，the maximum dry density of filler can meet the compaction standard of high-speed railway subgrade. The research results can be used to popularize the vibration compaction method，and also help to deepen the understanding of the mechanism of vibration compaction.

Volume and deformation measurement is in great significance for characterizing soil and rock mechanical behavior. In this paper，a new dynamic image-based multi-camera and multi-media photogrammetric method is proposed to measure soil deformation during triaxial testing under dynamic loading. With videos captured by multiple cameras from different view angles，dynamic images can be extracted. Together with the camera calibration results based on dynamic images and the multi-media photogrammetric method，volume and deformation of soil during triaxial testing can be measured under dynamic loading. With help of a six single lens reflex camera video capturing system，triaxial test was conducted on a steel cylinder and two silt specimens to validate the feasibility and full-field deformation measurement capability of the proposed method. Triaxial test on steel cylinder shows that the volume measurement can be made based on dynamic images at a high accuracy. The result from the triaxial test on silt specimens demonstrates that the proposed method is capable of continuous soil volume and full-field deformation measurement under dynamic loading. The proposed method overcomes the limitations associated with the conventional methods and extends the application of the multi-media photogrammetric method from static loading condition to dynamic loading condition. Continuous volume and full-field deformation measurement are beneficial for advanced characterization of soil behavior under dynamic loading.