In order to study the hydro-mechanical coupled shear rheological mechanisms of rock joints，a hydro-mechanical coupled shear rheological testing system for rock joints was independently developed. The test system is equipped with a specially designed shear box device，which can ensure that the maximum water pressure of 5 MPa can be provided in the process of shear test. The wrapping of the rubber sleeve around the specimen under the action of the confining pressure，and the combination of active and passive loadings are adopted to meet the tight fit between the circular indenter and the cubic rock sample to ensure that there is no leakage during shear test. Shear displacement can be produced in both directions simultaneously. Shear rheological test of joints can be carried out under servo control of constant normal stress(CNL) and constant normal displacement(CNV). Dynamic permeability of rock joints under different shear conditions can be conducted. Furthermore，hydro-mechanical coupled shear rheological test of structural planes under different hydraulic gradients and water pressures can be carried out. The accuracy and reliability of the system are verified by various tests of granite with different joint faces under different boundary conditions of hydraulic gradient and hydraulic pressure. The testing system provides a support for the study of hydro-mechanical coupled shear creep properties of rock joint，and has a certain guiding role in enriching and improving the theoretical study of rheological properties of rock joints.

In order to grasp the law of overlying strata movement and water-conducting fracture development in three-soft coal seam mining under thick loose layers. Taking Chenghe mining area as the background，using the similarity simulation experiment，comprehensively using the research method of the total station monitoring，high-definition borehole TV monitoring，3DEC software and SPSS professional statistical analysis software，and introducing the mining damage theory，the overburden migration law，fracture development and evolution，and distribution characteristics of water-conducting fracture zone were studied under this condition. The results show that the Overburden migration presents asymmetry，the subsidence extreme value of rock strata in different layers always deviates to the side of open-off cut，and the movement range of the loose layer is larger than that of the top layer of the bedrock，showing a“hyperbolic-like”shape as a whole. According to the theoretical formula，the fracture angle of the bedrock is relatively small，ranging from 56° to 58°. The height of the caving zone and the caving-mining ratio are 13.75 m and 3.06 respectively，and the height of the water-conducting fracture zone and the fracture-mining ratio are 75 m and 16.67 respectively. The number of fractures gradually increases from the surface to the bottom and suddenly increases in the water-conducting fracture zone. The development of fissures is controlled by the mining stress field in the 33° east by north direction. The evolution of the water-conducting fracture zone presents five stages which are“slow development，gradual increase，large and sudden increase，periodic small increase and stable development”. Through 3DEC simulation，it is concluded that the height of water-conducting fracture zone has an exponential function relationship with the thickness of loose layer，a linear relationship with mining height，and a logarithmic function relationship with buried depth and inclined length of working face. Using SPSS professional statistical analysis software，the empirical formula for predicting the height of the water-conducting fractured zone is fitted based on the multiple nonlinear regression theory. By comparing the calculation results，the rationality of the regression empirical equation in predicting the height of the water-conducting fracture zone is verified. Because the K5 sandstone aquifer has a large unit water inflow and is close to the coal seam. In order to avoid the mining of the coal seam from being affected by the overburden K5 sandstone aquifer. According to the obtained prediction empirical formula，the maximum mining height of the coal seam should not surpass 3.8 m. This research has important reference value for water-conservation mining in coal mine under similar geological conditions.

In order to study the evolution law of water inrush disasters in fault fracture zones，an experimental research on creep-erosion coupling mechanical characteristics of fault fracture rock masses was conducted in this paper. A novel test method，for infecting water around the inner of the seepage cylinder and loading in the axial direction，was invented and innovated，by which the core issue of radial migration of fine rock particles from the surrounding to the center under the action of seepage was broken through. A series of fluid-structure coupling tests of fault fracture rocks under multi-factor conditions were carried out，and the deformation and seepage characteristics of fault fracture rocks during variable-mass water inrush were obtained. The test results show that the variable-mass water inrush process can be divided into three stages，i.e.，the initial stage，the erosion period and the creep period. Among them，the erosion period is the key that determines the germination of variable-mass water inrush disasters，and during the creep period，the large deformation will induce the instability disaster of surrounding rocks. More significant creep effects can be observed in the samples with larger axial stress，larger bore diameter，lower water pressure and lower cementing strength. More obvious erosion effects can be observed in the samples with larger water pressure，larger inner diameter，smaller axial stress and smaller cementing strength. Among influencing factors，the axial stress and the cementing strength are the main controlling factors for the creep behavior of fault rocks，while the axial stress，the water pressure，the cementing strength and the bore diameter all have a great effect on the erosion behavior.

Sudden instability of hard brittle rock often brings disastrous consequences，so it is very meaningful to study the precursor information of sudden instability of hard brittle rock. In this paper，the true triaxial loading tests of red sandstone samples under different intermediate principal stress conditions are carried out. The thermal infrared thermal imaging evolution and temperature characteristics during rock fracture are studied adopting infrared thermal imaging technology，and the crack propagation source，crack propagation trend，acoustic emission characteristics and fracture evolution mechanism of rock under true triaxial loading are analyzed by using the acoustic emission and high-speed video technology. A non-contact pre-warning index of rock fracture based on thermal infrared is proposed，which can give early warning of rock failure before the abnormal temperature change caused by rock fracture. The results show that there are four kinds of precursory information before rock fracture，which are thermal infrared temperature precursory，acoustic emission precursory，thermal image anomaly precursory and rock macro crack precursory. The occurrence times of the thermal infrared temperature precursor and the acoustic emission precursor are relatively early，which can give priority to the early warning of rock failure. The occurrence times of the thermal image anomaly precursor and the macro crack precursor are relatively late， close to the specimen failure. Thermal image anomaly can indicate the potential fracture area of rock. In this paper，the thermoacoustic precursory information chain of hard brittle rock is established from the internal，external，temporal and spatial aspects of rock. The related research can provide a useful reference for the analysis and prevention of sudden rock failure.

After construction，shaft freezing walls will experience a long thawing process，creep deformation will occur under long-term loads. The creep behavior of frozen rocks during the thawing process is the key issue to control the long-term stability of the frozen walls. Based on the freezing engineering of the return air shaft in Xinzhuang Coal Mine，Gansu，this paper analyzes the creep mechanical characteristics of the frozen Cretaceous sandstone during the thawing process. At the same time，nuclear magnetic resonance technology is used to test the change of the pore water content during the thawing process to analyze the relationship between the unfrozen water and the sandstone strength. Based on the fractional order theory，a nonlinear creep constitutive equation is established. The results show that the pore water in rocks mainly presents three forms such as free water，capillary water and adsorbed water，mainly exists in the forms of free water at room temperature and adsorbed water at low temperature. During the thawing process of frozen sandstone，the long-term strength，gradually decreasing with increasing temperature，is about 45%–51% of the conventional triaxial compressive strength，and changes suddenly at – 4 ℃. It is also found that the long-term strength of the frozen sandstone is closely related to the unfrozen water content，showing an exponential function. The creep failure of the frozen sandstone is mainly due to the coupling of stress field，chemical potential field and seepage field，and the stress field plays a leading role. According to the creep deformation characteristics of the frozen sandstone during the thawing process，and introducing a fractional order function，a corresponding nonlinear creep equation is established based on the fractional order theory. The research results can provide theoretical and technical support for evaluating the instability and damage of frozen walls induced by the thawing.

The support reaction force of tunnels increases with time in viscoelastic-plastic rock mass，which makes the stress state of yielding surrounding rock in plastic zones move inward from the yield surface. Therefore，it is necessary to make clear the stress path of the surrounding rock when investigating the long-term mechanical characteristics of the interaction between rock and tunnel support. Considering the effect of the stress path，based on the generalized Kelvin model and Mohr Coulomb strength criterion，a simplified method for analyzing the viscoelastic-plastic stress，strain and displacement of the surrounding rock and the interaction between the support and the surrounding rock is proposed. In this paper，different kinds of“yield-resist combination”support technologies of high geostress soft rock tunnels are summarized into three categories as“yield before resist”， “yield while resist”and “control-yield-resist”. The influences of three kinds of support measures on the stress path of the surrounding rock are analyzed respectively. The deformation of the viscoelastic-plastic surrounding rock and the support reaction under different support measures are further studied. The results show that the calculated surrounding rock displacement is much larger if the stress path is taken into account. Under the condition of the same displacement release and the same stiffness of the lining support，the deformation rate of the surrounding rock at the initial stage is very large by adopting the measure of “yield before resist”，and the increasing support reaction force at the second stage is also the largest after applying the permanent support. It is most appropriate to adopt the “control-yield-resist”support measure under the condition of high geostress and serious deformation(for example，the initial stress exceeds 20 MPa). The prestress long bolt is employed to support the surrounding rock immediately after the tunnel excavation, which can not only control the deformation rate and improve the stability of the surrounding rock in the first stage，but also greatly reduce the additional support force and improve the stability of the lining structure during the second stage. Under the condition of low geostress and slight deformation(for example，the initial stress is less than 10 MPa)，the “yield before resist”measure can effectively control the deformation of the surrounding rock，and the “control-yield-resist” measure is not necessary. The “yield while resist”measure is applicable to the cases between the above two extreme conditions(e.g.，the initial ground stress is between 10 and 20 MPa). In addition，the deformation rate of the surrounding rock with a small viscosity coefficient is very large after excavation，for example，when the viscosity = 2×109 and 1×1010 Pa·d，the initial rock deformation rates are 17.6 and 3.5 cm/d respectively with the “control-yield-resist”measure. Therefore，for the surrounding rock with a small viscosity，large support reaction force must be applied immediately after excavation to control the deformation rate.

Grouting technology is a common reinforcement method for fractured rock mass. Grouting effect on rock mass is mainly reflected in the influence on mechanical properties of structural planes，and different grouting materials have different reinforcement effects and mechanisms. Taking red sandstone as the research object，the structural plane is made by splitting method，and the cement and the epoxy resin are selected for grouting materials. The direct shear tests under different normal pressures are carried out. The shear test results are compared with those of non grouting structural planes，and the shear mechanical properties are analyzed. The 3D scanner is used to scan the structural planes before and after shearing. Based on the calculation formula of the effective shearing angle and the root mean square slope Z2，the roughness of the structural planes before and after shearing is evaluated by using the analysis software，and the influence of grouting on the three-dimensional morphological characteristics of the structural planes is analyzed. The test results show that grouting can increase the cohesion between the structural planes，and change the three-dimensional morphology of the structural planes，so as to increase the shear strength. It is also shown that the mechanical properties of different grouting materials are different. Epoxy grouting material has a prominent effect on structural plane reinforcement，while cement grouting material has a significant effect at low normal stress level.

As a natural non-homogeneous material with self-bearing capacity，the failure process of rock masses has significant uncertainties. To establish a damage criterion that can be used to evaluate the failure of rock materials，the relationship between the critical damage and the plastic deformation was established by combining the strength criterion and statistical damage mechanics theory，and the plasticity index g was introduced into the damage evolution equation to derive two types of rock damage failure criteria. Triaxial compression tests on 17 sets of samples from two types of rocks were carried out to verify the reasonability and accuracy of the developed criteria. At the same time，based on the damage failure criteria established in the paper，a reference standard for the classification of the damage class of non-homogeneous materials was established，and the calculation method for the critical value of each damage class was given to explore the damage failure behavior of rock materials under different surrounding pressures. The results show that the test results are all within the 99% confidence band of the theoretical prediction values by the damage failure criterion established in the paper，indicating that the prediction accuracy is high. The larger the material plasticity index γ，the worse the homogeneity，and the smaller the rock compression and the tension ratio. The larger the critical damage Dcr，the better the damage resistance of the material，and the less sensitive the structural damage is to minor damage. With increasing the surrounding pressure，the damage rate of the rock material decreases rapidly，showing that the surrounding pressure has a suppressive effect on the damage of the material. The progressive failure process of rock materials can be divided into four damage levels including basically intact，minor breakage，moderate damage and severe damage，and the boundary values between the damage levels are directly related to the homogeneity of the materials. The above research results can quantitatively assess the damage state and damage limit of rock materials under different surrounding pressure environments，and give important theoretical guidance for the analysis of engineering rock damage failure.

There are seldom inverse researches of 21 elastic matrix coefficients of anisotropic rock mass at home and abroad. In this paper，the Walkaway VSP observation system for fine exploration of mine rock mass is designed by using the rock mass in-situ testing technology of “three-dimensional three component data acquisition of VSP excited by shear wave vibrator”. By using the formulas for calculating the slowness and polarization vectors of qP and qS waves based on the solution of Christoffel equation in anisotropic media，and taking the wave field parameters(slowness and polarization vectors) of qP and qS waves collected in situ as input conditions，the 21 coefficients of the elastic matrix of rock mass under the condition of complete anisotropy are obtained based on the combination of vertical and horizontal waves. Using the elastic matrix coefficients，the “three zones” anisotropy of the overlying rock is identified as HTI medium attribute，and the anisotropy parameters and engineering mechanical parameters of rock masses at different depths are calculated. The relationships between the “three zones” of overburden with the anisotropy parameters and the engineering mechanical parameters are analyzed. The results of this study make the forward calculation of rock mechanics and exploration seismology no longer depend on the assumption of the type of anisotropy of the target medium，and open up a new direction for the study of rock engineering mechanical properties.

Through investigation and analysis of production conditions of rock burst mines in China，it is found that complex geological conditions and isolated working faces are the areas with high occurrence frequency of rock burst，although rock burst often occurs in shallow buried，near horizontal，thin coal seam and non-structural areas as well. Almost all coal seams in rock burst mines have a burst liability，which indicates that burst liability is the internal cause of rock burst，therefore accurate evaluation of the bursting liability is the basis of coal bump risk assessment. This paper systematically summarizes the research progress of qualitative analysis and quantitative evaluation of coal burst liability，discusses the scientificity of the existing evaluation methods of coal burst liability and the corresponding theoretical and technical problems，and puts forward a comprehensive evaluation index which includes the strength，stress and energy evolution and dynamic failure time. The research results of qualitative analysis show that the content，distribution and primary defects of different mineral components in coal rock materials affect the macro deformation and failure behavior，and then determine the impact propensity. The characteristics of acoustic，thermal，electrical and magnetic signals released by coal and rock mass with different impact tendencies are significantly different，and water，temperature，specimen size and loading mode directly affect the test results of coal rock impact tendency. The progresses of five types of evaluation indexes of the bursting liability including strength index，time index，stiffness index，deformation index and energy index are summarized，and their scientificity and defects are discussed. Based on the linear relationship between the stress state and the elastic strain energy accumulation，the elastic energy accumulation at the peak strength is calculated，the comprehensive evaluation index considering the strength，stress and energy evolution and dynamic failure time is established，and the corresponding classification critical value is proposed.

When simulating the failure of brittle rock，existing studies based on the flat joint model neither consider the nonlinear characteristics of stress-strain curve caused by inherent microcracks，nor take the crack initiation stress，an important indicator of damage evaluation，as the calibration benchmark for micro parameters. Therefore，this study used uniaxial compressive strength，elastic modulus，Poisson's ratio，stress-strain curve characteristics，crack initiation stress，Brazilian splitting tensile strength，Coulomb friction angle and cohesive force as the benchmark to calibrate the micro parameters of the flat joint model for simulating granite failure. The trend relationships between the macro mechanical behaviors and micro parameters were analyzed. The calibrated parameters were used to establish an accurate flat joint model sample，which was compared with a conventional flat joint model sample that does not consider inherent microcracks. Numerical tests of fractured rock compression were carried out. Based on the strain field obtained by the digital image correlation method of the indoor test，the initiation，quantity and distribution characteristics of tensile/shear microcracks were analyzed to verify the calibration process of the flat joint model proposed in this paper. The results show that inherent microcracks influence the characteristics of the stress-strain curve at the macro level，and have a great impact on the crack initiation mode at the tip of the prefabricated flaw and the propagation and distribution law of tensile-shear microcracks at the meso level.

Deep rock tunnels are often in complicated true triaxial stress state and the mechanical behavior of the surrounding rock is significantly different from that in shallow tunnels，resulting in that the commonly applied strength criteria and tunnel design methods obtained from shallow tunnels cannot meet the requirement of the refined rock stability analysis for deep tunnels. The three-dimensional(3D) space effect near tunnel faces is often simplified or ignored in design and operation of a shallow tunnel，but its influence on rock stability and construction safety of deep tunnels must be paid enough attention to. The 3D geological model and tunnel numerical calculation model were established according to a typical deep rock tunnel in western China. Based on the GZZ strength criterion，the 3D finite element numerical simulation of the excavation process of tunnels with different buried depths was carried out to study the 3D and non-linear space effects of the deep tunnel face，and thus to reveal the complicated stress path and the time-dependent evolution mechanism of non-linear extrusion deformation during the deep tunnel excavation. The research results show that：(1) the input parameters of GZZ strength criterion such as rock mass GSI can be quickly，automatically and accurately obtained with the help of digital acquisition technologies such as on-site 3D photography，laser scanning and 3D reconstruction，which helps to realize the 3D positive analysis of the surrounding rock stability；(2) the extrusion deformation of the excavation face of a deep-buried tunnel，more significant than that of a shallow-buried tunnel，is mainly plastic and shows a parabolic nonlinear relationship with the buried depth，while the plastic yield state of the excavation face precedes the surrounding rock；(3) there is a significant 3D space effect in the range of 3 - 4 m before and after the tunnel face，and all the three principal stresses undergo tremendous changes accompanied by an obvious rotation of the principal stress axis，which are mainly caused by the sharp increase of the shear stress at the tunnel face；(4) the stress level I1 at the core of the tunnel face is much lower than that of the surrounding rock，but the instability of the tunnel face caused by excavation unloading is more serious than that of the surrounding rock caused by loading；and (5) the distortion of the steel arch and the non-uniform longitudinal deformation of the surrounding rock in deep-buried tunnels are mainly related to s3 and s2，and the effect of s2 increases significantly when the buried depth exceeds a certain depth.

The strength and hardness of frozen rock are several times higher than those of rock at room temperature，which leads to high excavation cost and low excavation efficiency of frozen rock layers. A new idea of employing microwave irradiation as an assisted method in excavation of frozen rock strata was proposed，which does not depend on whether the rock contains absorbing minerals and can be applied in a wide range of strata. In this paper，the quartz sandstone，which does not contain absorbing minerals，was used to explore the law of thermal melting and softening behaviors of frozen rocks under microwave irradiation. The underlying damage mechanisms were discussed and summarized based on the observation of the mesopore structure of samples before and after microwave irradiation. The results show that：(1) thawing of frozen sandstone has three stages under microwave irradiation，including rapid melting of pore ice，intense vaporization of melt water and sample drying，(2) microwave irradiation has a significant softening effect on frozen sandstone，and the strength of frozen sandstone after microwave irradiation decreases to one-fifth of that before the irradiation，and (3) the softening of saturated frozen sandstone under microwave irradiation is primarily caused by vaporization expansion effect and thermal expansion effect. The vaporization expansion effect causes the propagation of intergranular cracks，while the thermal expansion effect may induce trans-granular cracking. This study provides theoretical and experimental support for microwave-assisted breakage of frozen rock.

Pore structure is an important factor in rock mass quality evaluation，reservoir classification and seepage characteristics research. Continuous quantitative analysis of pore structure in whole well section is still a difficult problem. Based on the feature that the optical image of the hole wall continuously records the structural information of rock mass in the whole well section，a method for accurate identification and quantitative analysis of rock pore structure is proposed. Firstly，according to the difference of different structure information in the optical image of the hole wall，the effective identifications of drilling fluid，dark gray shading of rock and pore structure are realized by reasonably adjusting the R，B and G components of the image and converting the color space. Then，the best threshold binarization and morphological operation are carried out on the optical image of the hole wall，and the accurate recognition of the rock pore structure is completed. On the basis of accurate identification of the pore structure，combined with the depth and orientation information attached in the optical image of the hole wall，a calculation method of the surface porosity and the linear porosity is proposed. Combined with specific cases，the pore structure distribution analysis and particle size statistics along the depth and orientation of boreholes are completed. The research shows that based on the rock structure information in the optical image of the hole wall，the automatic identification and statistical analysis of the pore structure can be realized，which provides a new idea and method for the continuous research of rock pore structure in the whole well section.

Under the action of cyclic blasting dynamic loads，it is necessary to determine a reasonable anti-outburst thickness for the hazards of water inrush on the side walls of karst foundation pits. First，according to the mechanical characteristics of water inrush from the sidewalls of the foundation pit，a mechanical model of the truncated cone is established to prevent the instability and damage of the outburst layers. Using the cusp catastrophe theory and energy discrimination method，the anti-outburst layer potential function and the bifurcation point set equation are obtained, and the expression of the anti-outburst thickness of karst foundation pits is deduced. Furthermore，in the blasting excavation，the blasting cumulative damage model is introduced from the perspective of rock fatigue damage，and the cumulative damage value of cyclic blasting is obtained. At the same time，the elastic modulus of the anti-outburst layer is revised to form a calculation method for the anti-outburst thickness of karst foundation pits considering the number of cyclic blasting. Finally，based on the Suoyuwan South Station of Dalian Metro Line 5，the outburst prevention thickness is calculated，the parameter sensitivity analysis of the main influencing factors is carried out，and the concrete outburst prevention construction measures are put forward. The research results show that the anti-outburst thickness of karst foundation pits under different blasting times can be obtained by introducing the blasting cumulative fatigue damage variable. The anti-outburst thickness increases with decreasing the rock elastic modulus E，the Poisson¢s ratio m，the pressure diffusion angle θ and the steel support axial force F1，but is positively correlated with the karst water pressure F3，the karst zone radius R2 and the number of blasting n. In the sensitivity analysis of various influencing factors，the karst zone radius R2 and the karst water pressure F3 have the most significant influence on the thickness of anti- outburst，and the sensitivity factors are 0.869 and 0.722 respectively. This method and conclusion have good reference value for the design and safe construction of rock foundation pits under blasting excavation in karst areas.

The urban ground collapse that often occurs is mainly soil cave collapse，and the contents of clay particles in the bedrock overburden have an important influence on the stability of soil caves. Clay particles mainly containing kaolinite are selected and mixed with coarse silt particles to form a remolded soil cap layer with different percentages of clay particles. The relationship between the contents of clay particles and the permeability coefficient of the soil layer is obtained through experiments. According to the permeability coefficient，the experimental soil layers are divided into two basic layer structures，namely，water-permeable and water-blocking cover layers. The stability of spherical soil holes with different radii in these two types of soil caps is studied through indoor model tests. The results show that stable soil caves cannot be formed in sandy soil caps without clay particles，and that the permeable soil caps cannot form large soil caves and the small soil caves have poor stability. It is also revealed that the water-blocking soil cap layers can form large soil caves close to the critical roof thickness，that the stability of the soil caves increases with increasing the clay particle content and that the soil cave with a clay particle content about 30% has the best stability. Based on the test results and engineering phenomena，the common ground collapses of the overburden are divided into two types including dish-shaped collapse and cylindrical collapse，and their damage mechanisms and hazards are explained.

In order to solve the problem that the intermediate principal stress is not considered in the traditional foundation bearing capacity formula，the Mohr-Coulomb yield criterion describing the limit equilibrium state of foundation soils is replaced with the double shear unified strength theory considering the action of the intermediate principal stress. Using mathematical derivation and computer programming methods，the parameter substitution method and theoretical derivation methods(including explicit and implicit theory derivation methods) for calculating the foundation bearing capacity are proposed. Firstly，the expression of the double shear yield function expressed by the shear strength parameter is derived by assuming compression being positive. Then，the applicable condition and substitution steps of the parameter substitution method are put forward，and the unified internal friction angle and unified cohesion under plane strain condition are derived. The applicable conditions of the theoretical derivation methods are also proposed，and the calculation steps of the implicit theory derivation method are encapsulated into F-C functions using MATLAB software. Finally，the parameter substitution method and theoretical derivation method are used to calculate the foundation bearing capacity of a typical shallow strip foundation. The results show that the foundation bearing capacity calculated by the parameter substitution method is consistent with that by the theoretical derivation method，and the foundation bearing capacity increases with increasing the influence coefficient of the intermediate principal stress. To sum up，both the parameter substitution method and the theoretical derivation method are applicable for the calculation of the foundation bearing capacity，the contribution of the intermediate principal stress to the foundation bearing capacity cannot be ignored，and the foundation bearing capacity calculated based on the twin shear unified strength theory is more reasonable.

In order to investigate the vertical vibration characteristics of large-diameter pipe piles embedded in bidirectional inhomogeneous soils，a mechanical model for longitudinal vibration of large-diameter pipe piles in radial inhomogeneous layered soils is established by considering the lateral inertia effect of large-diameter pipe piles and construction disturbance，based on the Rayleigh-Love rod model and Novak¢s plane-strain theory. The complex stiffness expression at the interface between the soil and the large-diameter pipe pile is obtained recursively by means of the Laplace transform and complex stiffness transfer techniques. Then the analytical solution for the dynamic impedance of large-diameter pipe piles is derived by using the completely coupling condition between pile and soil and the transitivity of the impedance function，and compared with the previous solutions to verify the validity and precision. Furthermore，parametric analyses are performed to investigate the effects of the parameters of pile and soil on the dynamic impedance of a large-diameter pipe pile. The results show that the Rayleigh-Love rod model and the relevant analytical solution are more appropriate to analyze the longitudinal vibration characteristics of large-diameter pipe piles than Euler-Bernoulli rod model which underestimates the amplitude and resonance frequency of the dynamic impedance. Keeping the inner(outer) diameter constant，the larger(smaller) the outer(inner) diameter，the higher the amplitude and resonance frequency of the dynamic impedance at the pile head. The softer(harder) the longitudinal interlayer of the surrounding soil，the larger the peak difference of the dynamic impedance curves. The greater the degree of softening(hardening) of the surrounding soil，the larger(smaller) the amplitude and resonance frequency of the dynamic impedance at the pile head. The disturbance range has a significant effect on the oscillation amplitude while little influence on the resonance frequency.