To study the failure mechanism of deep roadway surrounding rock，a novel large-scale physical model test system with dynamic-static loading is developed. This test system consists of main frame，loading box，box moving platform，static loading system，dynamic loading system and roadway reaction device. Complex loading conditions of “high static loading + dynamic disturbance loading” can be realized. Based on the stress evolution process of deep roadway surrounding rock，the verification test is carried out. Test results show that the test system has advantages of compact frame structure，high box mobility and simple system operation. Synchronized and uniform step loading in the axial and lateral directions can be realized by the static loading system. It has the function of long-term load retention. Disturbance of cyclic loading-unloading according to the pre-set waveform can be carried out by the actuator of dynamic loading system. Single impact disturbance can be achieved by the axial drop-weight or lateral pendulum disturbance device. Roadway excavation can be simulated by the roadway reaction device. However，it is not convenient to observe the deformation and failure process of roadway surrounding rock. The further research will be carried out by manual excavation. The stress distribution law of roadway surrounding rock is consistent with the field investigation. Dynamic-static loading environment can be simulated，and large-scale physical similarity model test of deep roadway can be carried out by the test system. It has great significance for studying the dynamic-static load inducing rock burst mechanism，the deformation and failure law of roadway surrounding rock，the “stress relief-support reinforcement” synergetic control theory and the far-field energy attenuation mechanism.

In order to research the creep mechanical property of peridotite which was taken from the Anding Tunnel of the Yumo Line of the China-Laos Railway，creep test under different confining pressures and conventional compression test were carried out. The test results show that the ratio of the elastic modulus of saturated peridotite specimens to that of dry specimens is close to the softening coefficient peridotite. Meanwhile，the Poisson?s ratio of the saturated peridotite specimens is slightly larger than that of the dry specimens. The instantaneous strain produced after peridotite loading is mainly elastic strain，and peridotite has a creep initiation threshold. When the axial deviatoric stress is lower than the creep initiation threshold，the peridotite only has instantaneous strain without creep strain. Only if the axial deviatoric stress is larger than the creep initiation threshold，creep phenomenon occurs in peridotite. As the surrounding rock pressure increases，the creep initiation threshold and accelerated creep threshold of peridotite have a linear increasing trend. Based on the creep mechanical property of peridotite above，a creeping model of 7-element nonlinear viscoelastic-plastic was established to describe the creep behavior of peridotite. At the same time，the rationality of the model was verified by the creep test results. The results show that the established model can better reflect the creep mechanical behavior of this kind of rock.

Twenty-nine groups of cube specimens with a size of 70.7 mm were prepared to explore the mechanical properties of the multi-source coal-based filling body of solid wastes. The compressive strength of the filling specimens at different ages was obtained by using an uniaxial compression test system. The micromorphology and material composition of the raw materials were analyzed by XRD and SEM，and the cross-section micromorphology of the specimens at different ages was collected，to reveal the strength evolution law of the filling body. The effects of each component on the filling body strength at different ages(3，14，and 28 d) were studied based on the response surface method，and the acoustic-emission characteristics of the specimens in the whole failure process were monitored adopting an acoustic-emission test system. The results show that the influence of fly ash on the strength of the specimen is most significant，followed by gangue，desulfurization gypsum and 1∶1 mixture of gasification slag and bottom slag. Analysis by the response surface method presents that fly ash and gangue significantly affect the compressive strength of the filled specimens. The newly formed rod-shaped crystals and honeycomb cotton-flock cementitious materials gradually increase with age，which increases the strength of the filling body. The strength of the specimens at 3 d age is the maximum，and the increment of the strength of the specimens increases is largest at 3–14 d age followed by that at 14–28 d age. At the plastic-deformation stage，a few ring counts and small-amplitude energy release exist，and fine cracks appear on the specimen surface，which gradually evolve into through cracks. At the yield failure stage，the acoustic emission ring count increases sharply，and the energy accumulated in the specimen is released suddenly through the cracks on the specimen surface，resulted in the specimens to gradually crack and collapse. At the post-peak stage，the specimens still have a certain strength，and the acoustic emission event is still active，accompanied by energy release. The research results provide a basis for optimizing the filling-material ratio in the engineering site.

Similar simulation test is an important research method for solving the safety problems of deeply buried caverns under high yield explosion. For a long time，however，the relevant researches have been difficult to carry out effectively due to the limitations of technical means and equipment. A three-dimensional simulation test system for ground impact effects in deeply buried caverns was developed by combining self-development and necessary borrowing，which solves the key technical problems of flexible and uniform long-time loading of high ground stress，fine adjustment of ground shock waveforms and the combined static and dynamic loading with high ground stress and ground shock. At 1∶50 to 1∶100 geometric and physical similarity，the device can realize the simulation of high ground stress loading，excavation disturbance process and explosive ground impact effect. With the equipment，the technical problems of limited prototype testing and lack of simulation means are solved. The test system was used to investigate the response mechanism of deep tunnels under combined dynamic and static loads. The results show that outside the safe burial depth boundary of the project designed according to the ultimate stress of the homogeneous rock mass，ground impact disturbance can still activate the movement of structural rock masses in the deeply buried rock mass，causing serious local damage to the construction. The test results show that the device operates stably and reliably，and can realistically reproduce the destruction process of deeply buried cavernous chambers under impact disturbance. It provides a reliable foundation platform for researches on the safety and protection of deeply buried caverns against large yield explosion impacts.

The precursor of acoustic emission(AE) can reveal the internal destructive rules of coal. Therefore，the discrimination model based on AE precursor has been a hot topic on the monitoring and prediction of coal failure. Based on DenseNet architecture combining with Group Convolution(GC) and Squeeze-and-Excitation module(SE) in attention mechanism，a lightweight three-dimensional(3D) convolution prediction model was proposed to integrate spatiotemporal information of AE signals. The coal samples from the No.3－1 coal seam of Hongqinghe mine，with high outburst-proneness，were used in the tests. AE signals were collected during the uniaxial compression of samples in different loading rates. Moreover，AE signals were preprocessed to generate spatial-temporal image sequences which were later used as model input to predict the destruction level of coal samples. Then，transfer learning was employed to predict the remaining failure time of coal samples. The results show that： in the validation samples for predicting the destruction level，all the networks(DenseNet，DenseNet+GC，DenseNet+SE and DenseNet+GC+SE) can obtain more than 99.08% prediction accuracy. The recall rate of high-risk samples prediction is higher than 99.50%，which indicates that 3D convolution can effectively capture spatial-temporal information of AE. The prediction probability of the DenseNet+GC+SE network is exhibited as unitary distribution，indicating the model can distinguish different destruction levels. Group Convolution and SE module can retain model accuracy while reduce the structure and time complexity，which improve DenseNet+GC+SE network efficiency greatly. The R2 between the predicted value and the true value of the remaining failure time is 99.85%，which further proves that DenseNet+GC+SE transfer model can effectively predict coal failure based on AE signals. The diversity of AE features is represented by GC，while the importance of AE features is evaluated by SE module.

The rock slopes in high-intensity areas are developed with cracks and distributed randomly. The deformation damage of the rock slopes will occur when they evolve into shattered rock mass after suffering multiple phases of strong earthquake. Therefore，it is significant to explore the shattering cumulative effect of multiple phases of strong earthquake on the stability of the step-like rock slopes. In this paper，the shattering cumulative effect of the step-like rock slope was mainly researched via analyzing the dynamic displacement response of the step-like rock slope model，which was performed by means of the large-scale shaking table model test. The residual deformation was represented by the baseline offset，the ultimate failure on the surface of the slope model was induced by the mutual effect of residual deformation and dynamic deformation caused by seismic excitation. The shattering cumulative effect was analyzed via the proposed residual deformation ratio，and the application of this analysis method was verified by Arias-Intensity magnification. The results show that the residual deformation ratio can analyze the shattering cumulative effect of the slope more clearly，which sufficiently considers the mutual effect of the continuous residual deformation and seismic dynamic. The deformation and failure of the step-like rock slope start from local regions，in which the interior fold line of the step platform and the top of the step-like slope are the areas prone to develop with incipient cracks. Based on the analysis of residual deformation and Arias-Intensity energy，the shattering cumulative process of the slope is concluded in three steps，including slow deformation，accelerated deformation and unstable failure. These two methods can be alternately adopted in analyzing，helping achieve a more precise prediction of the dynamic deformation of the slope and presenting a more credible reference for the design of earthquake fortification scheme for slopes.

To investigate the prestress state of prestressed anchor cables in service，a new prestress test model was established. This model is based on tangential stiffness theory and considering the structural transfer effect of external anchor segment under working condition，and verified by static and dynamic loading tests. By simplifying the rough contact interface between the anchor and anchor base plate of the external head segment as an anchorage-contact model，and based on Hertz contact theory and GW statistical contact model，this test model transforms the measurement of cable?s prestress into the identification of the tangential contact stiffness of the contact surface，then obtains the quantitative tangential stiffness of the external anchor segment and the calculating formula of anchor cable prestress，from the measured tangential load and displacement. The static and dynamic loading tests indicat that，the average relative error between the experimental and theoretical values of tangential stiffness and prestress is 7.41%，while this error is within 10% by measuring through elastic wave. These results support the correctness of the anchorage-contact model at external anchor head segment，and the feasibility of the tangential stiffness test method. This test method provides a new effective and nondestructive measurement for the prestress of anchor cables in service.

Determining arrival time of microseismic P-wave is one of the key steps in microseismic data processing. In order to accurately determine arrival times of microseismic P-wave，according to the characteristics of different noise pollution degrees in different channels and periods of microseismic signal，the signal-to-noise index(SNI) superimposed by normalized signal-to-noise ratio(SNR)，the apparent degree of the signal(ADS) and the apparent degree of the jump point(ADJ) is used instead of SNR to quantify the quality of microseismic signal. Taking SNI as the judgment condition，the high-quality signal input is selected to improve the microseismic arrival accuracy. The method determining arrival times of microseismic P-wave(QONSL method) was designed based on quality optimization and normalized STA/LTA method. To test the feasibility and effectiveness of this method，the test data and microseismic monitoring data of Wulong Mine in Fuxin were processed respectively. The processing results of the test data show that when quantifying the quality of microseismic signal，the SNI is more accurate than the SNR，and the larger the SNI is，the closer the picking result is to the accurate time. The data processing results of Wulong Mine in Fuxin show that the QONSL method can quickly target the channel with higher signal quality and pick up the arrival times of microseismic P-wave through SNI. According to the arrival time picking results of 120 microseismic signals，the error with the accurate arrivals is kept within 5 ms，and the arrival error of 86 microseismic events is controlled within 2 ms. Compared with the STA/LTA algorithm，the overall picking accuracy of QONSL algorithm is improved by 72%，and the fluctuation of the global error range is reduced by 75%. The QONSL method is less affected by noise and has higher picking efficiency and accuracy，which can provide a reference for the hydraulic fracturing of the coal seam，the real-time monitoring of mine dynamic disaster，and the subsequent automatic high-precision positioning calculation of microseismic.

In order to study the crack evolution characteristics of cemented tailings backfill under uniaxial compression. The electronic universal testing machine，acoustic emission(AE)，scanning electron microscope (SEM) and DIC technology were used to conduct damage tests on cemented backfill under uniaxial loading. The multi-scale evolution process of cemented backfill from micro-crack initiation，expansion and coalescence to macro-crack generation was investigated. The results show that：(1) The damage mode of the specimen during uniaxial compression is ductile damage，and the crack penetration is in the form of shear penetration. (2) The micro-cracks and pores in the cemented filling body are scattered and randomly distributed. The internal morphology is mostly in the form of blocks，clusters and sheet networks. The internal structure is compact and has good integrity. (3) Crack expansion of samples present as tension crack at the beginning of loading and later as shear crack. The two act together to produce macroscopic primary and secondary cracks. Eventually，the connection between cracks leads to the destruction of the specimen. (4) The strain variation at different monitoring points at the same moment is related to their position in the specimen space. The closer to the lower end of the specimen，the greater the strain and the greater the strain change. The existence of a critical damage region for the specimen makes the difference between elastic and plastic strains and strain increase obvious.

To propose a new surrounding rock pressure calculation method for super-large-span highway tunnels，based on the construction mechanics theory of adjacent tunnels，this paper studied the influence between the surrounding rock pressures of each pilot tunnel excavated in sequence，and analyzed the interaction mechanism of each pilot tunnel excavated in sequence. By selecting 5 typical highway tunnels with four lanes in a single hole at three different regions，the monitoring data of surrounding rock pressure of 18 cross-sections of grade III，IV and V rock mass constructed by upper-lower bench method and upper-bench CD method were obtained，and it was found that the surrounding rock pressure of the rear pilot tunnel was generally affected by the excavation of the first pilot tunnel，and the pilot tunnel influence coefficient was proposed to quantitatively analyze the influence of the first pilot tunnel excavation on the surrounding rock pressure of the rear pilot tunnel. Then，the variation rate of the surrounding rock pressure in the current tunnel code was modified，and finally a calculation method of the surrounding rock pressure of the super-large-span tunnel considering the sequential excavation was proposed. The results show that：(1) The parallel(left and right) tunnels have a significant impact on the peripheral stress，while the overlapping(upper and lower) tunnels have limited impact on the peripheral stress. The combined impact of the left and right parallel pilot tunnel excavation on the surrounding rock pressure should be considered；(2) The influence coefficient of the pilot tunnel is mainly greater than 1，and the average values of Grade IV and V surrounding rock are 1.12 and 1.28 respectively；(3) Based on the current tunnel standard，the revised variation rate of the surrounding rock pressure was proposed，which is = 0.017(S－1)；(4) Compared with the calculation method of the surrounding rock pressure in the current tunnel standard，the Grade-IV and Grade-V surrounding rock pressures calculated by the proposed method in this paper are reduced by 14.6% and 2.4% respectively，which are closer to the measured values.

Infiltration effect exists in the process of low permeability porous media infiltration grouting，resulting in uneven spatial distribution of slurry particle concentration and viscosity，which seriously affects the grouting effect. Through one-dimensional visual grouting test，the occurrence conditions and influencing factors of percolation effect were studied，and the spatial distribution expression of the viscosity attenuation rate considering the influence of the water-cement ratio was obtained，and a theoretical formula of Bingham fluid column seepage grouting considering the spatial attenuation of viscosity was derived. Based on computer programming technology and relying on Comsol Multiphysics platform，the two-dimensional numerical simulation program of the theoretical formula was obtained by the secondary development. On this basis，the simulation analysis and model test under different grouting pressures and water-cement ratios were carried out to verify the correctness of the theoretical mechanism. The results show that the concentration and viscosity of grout particles decrease obviously along the seepage path when the seepage effect occurs，and the diffusion radius and permeability pressure obtained by adopting the Bingham fluid column seepage grouting diffusion formula considering the spatial attenuation effect of viscosity are closer to the measured values. Therefore，the spatial attenuation of viscosity caused by percolation effect cannot be ignored，and the new theoretical formula can better reflect the diffusion law of Bingham fluid when percolation effect occurs in low permeability strata. The research results can provide theoretical and technical support for grouting design and construction of low permeability strata.

In order to study the dynamic response characteristics of road-metro tunnels and surrounding soil under train vibration loads，based on the time domain and frequency domain analysis，the dynamic response characteristics of tunnel segments and internal structures，as well as the attenuation characteristics of vibration wave in the stratum are studied by using the method of model test combined with numerical simulation. The results show that in the full frequency domain under train loads，the dynamic response of tunnel segments increases with the frequency，while the dynamic response of the upper lane of the internal structure first increases(0–140 Hz) and then decreases(140–200 Hz). As for the attenuation amplitude of dynamic response at different positions，the upper lane is the largest，its average attenuation amplitude of response is 20.05 dB，and the attenuation amplitude of the peak acceleration in the corresponding time domain is 72.6%. In addition，the dynamic response of the tunnel structure will increase because of the moving effect of the train vibration load. Specifically，the peak acceleration at the track bed increases by about 105%，the side wall of the internal structure increases by 41.9%，the connection between the side wall and the upper lane increases by 47.3%，and the center of the upper lane increases by 22.3%. In the process of single train vibration load，the displacement of the tunnel structure meets its maximum at the arch bottom，with a peak value of 3.85 mm.

A set of dehydration tests of weakly expansive soils experienced different drying and wetting cycles were carried out by using the improved true triaxial apparatus for unsaturated soil to investigate the influence of drying and wetting cycle and volume change on soil water characteristic curve of expansive soil，and the water content and void ratio after each stage of dehydration were measured. The results show that with the increase of drying and wetting cycle，the pore ratio increases after saturation and decreases after dehumidification. The water content and void ratio of expansive soils after drying and wetting decrease with an increase in suction. Under the increasing of matric suction，the curves of the water content and the degree saturation with suction appear cross phenomenon，and the void ratio and suction curves appear cross-convergence phenomenon. With the increase of drying and wetting cycle，the volumetric moisture content and degree of saturation of expansive soils after dehydration decrease，which reflects the coupling effect of soil water characteristics and volume change of expansive soils after drying and wetting cycles. Based on Fredlund-Xing model，a SWCC equation expressed by the water content considering the influence of drying and wetting cycle is constructed，and the volume change equation of expansive soils considering the influence of drying and wetting cycles is established. Finally，the SWCC equation expressed in degree of saturation considering the effects of drying and wetting cycles and volume change is obtained. These three models can well describe the change rules of the water content，the void ratio and the degree of saturation of expansive soils after different drying and wetting cycles.

In order to explore the strength and deformation differences of the interface between saline soil and concrete in different areas，using self-made sodium sulphate saline soil and concrete samples，a series of monotonic direct shear tests were carried out under different salt contents，initial dry densities and normal stresses. The effects of different factors on the interfacial shear strength were studied，and the variation laws of the interfacial shear strength parameters and dilatancy under different salt contents were analyzed. The results show that the deterioration of the interfacial shear strength is caused by the salt content. If the pore solution of saline soil is in unsaturated state，the deterioration is weakened with the increase of the salt content. Otherwise，the degradation effect is increased. The enhancement effect of the initial dry density on the interfacial shear strength is inhibited by saline soil. The average failure shear stresses of the interface with salt contents of 1% to 4% under different vertical stresses are respectively 0.71，0.75，0.86 and 0.77 times that of plain soil，and the salt erosion reduction coefficient of the interface varies in the range of 0.68–0.88. As the salt content increases，the interfacial cohesion is enhanced，and the same trend as the shear strength is shown in the internal friction angle. In addition，the interface cohesion is more significantly affected by the salt content. Under the condition of a lower normal stress and a higher salt content，dilatancy is appeared in the interface，and shear shrinkage is shown in other cases. The shear shrinkage increases with the normal stress，and the minimum value is obtained when the salt content is 3%. The interfacial dilatancy angle increases significantly with the increase of the salt content in the range of 0% to 3% of the salt content. Besides，the increase of the interfacial dilatancy angle is restrained by a higher normal stress and the effect of the salt content on the dilatancy angle is weakened under the same condition.

The offshore and seabed silty clays are typical chloride saline soils since they are soaked in seawater. This paper aims at characterizing the frost heave mechanism of chloride silty clay. A series of open-system one-dimensional frost heave tests were conducted on chloride silty clay to investigate the frost heave and water-salt migration during freezing. The Nuclear Magnetic Resonance(NMR) relaxometry tests were performed to obtain the pore-size distribution of specimens at a specific time of interest during freezing. The internal relationship between microstructure change and frost heave was discussed. The results of open-system one-dimensional frost heave tests indicated that the propagations of freezing front，water-salt migration and frost heave were dependent on the salt content. The freezing front quickly developed，moved at a high rate and then gradually stabilized. The location of the freezing front at the thermal equilibrium was farther away from the cold end in a lower-salt content specimen. The water potential gradient was higher in lower-salt content specimen，driving more water-salt migration. The frost heave decreased with increasing the salt content and the solution intake induced frost heave dominated in the total frost heave. At the end of freezing process，the frost heave ratio increased and then decreased with increasing the salt content. It was found out that a threshold(i.e.，1% salt content) existed，at which the minimal frost heave ratio could be identified. The NMR results indicated that mesopores account for the main part of specimen voids and mesopores transformed into macro- and micropores during freezing. The lower the salt content，the greater the transformation ratio of the pore volume. For that more amount of water-ice phase change can be identified in low-salt content specimen，leading to more significant microstructure change. Consequently，the specimen with lower salt content experienced a larger amount of frost heave.

Unbound permeable aggregate base(UPAB) materials are increasingly used in foundation layers of porous or permeable pavements due to their desired drainage performance. The compaction quality of such layers directly affects critical in-service performance including post-construction settlement and durability. This paper conducted both conventional impact and newly-developed vibratory plate compaction tests on such UPAB materials Seven different UPAB gradations were designed by using the gravel-to-sand ratio(G/S) concept to represent different types of packing structures. The effects of gradation，compaction method and corresponding energy level on macroscopic compaction characteristics and particle breakage were studied. The optimal combination of vibratory parameters was identified. The normalized curves of achieved dry density versus degree of saturation were proposed and verified preliminarily. Such normalized curves are insensitive to variations in gradation，compaction method and energy level for similar aggregate types. The high-precision X-ray CT(XCT) scanning technology was employed to comparatively study meso-scale characteristics of particle movement，internal pore structure and connectivity of UPAB specimens with different gradations and vibratory parameters. It was found that the G/S concept-based gradation design method can effectively differentiate UPAB packing structures. There appeared to exist an optimal G/S range in terms of desired achieved dry density，particle breakage，and pore structure. The achieved dry density versus time curves of UPAB specimens obtained from vibratory compaction tests exhibited three distinct stages. The optimal vibratory frequency was found to range from 25 to 27 Hz，whereas there existed the most effective combination of vibratory force and duration time that yields the greatest dry density. The XCT results further substantiated macro-scale compaction characteristics. The curves of normalized achieved dry density versus degree of saturation could be useful for improved evaluation and control of field compaction quality of such UPAB layers in engineering practice.

The inverse analysis method for obtaining shear stress-strain response in soil based on acceleration array records has been applied in model tests and strong earthquake observations，but there are few studies on calculation of the corresponding shear modulus and damping ratio. A set of dynamic centrifugal model tests are used to discuss the characteristics and influencing factors of dynamic modulus，maximum modulus and damping ratio with the inverse analysis method based on acceleration array records，and its reliability is evaluated in combination with the classic formula. The results show that the dynamic modulus and the damping ratio are concentrated in the shear strain range of 0.01%—1%，and the data scatter is small. The variation trends of the dynamic modulus and the damping ratio with the shear strain，buried depth and void ratio are consistent with the general consensus，which reflects the rationality of the integral method and shear beam distribution function. The dynamic modulus and damping ratio data under different buried depths and loadings all obey the Hardin hyperbolic model well，and the correlation coefficients are larger than 0.98 and 0.97，respectively. The maximum modulus is negatively correlated with the void ratio and grows linearly with the buried depth，which proves the compacting effect of the vibration loads on the soil. Compared with the soil element test results，the shear modulus obtained in the model test is slightly lower while the damping ratio is slightly higher，which are related to the stress boundaries and loading methods of the element tests. The inverse analysis reliability of the shear stress-strain constitutive relation，shear modulus and damping ratio in dynamic centrifuge model tests is estimated qualitatively and quantitatively. The research work and conclusions provide important suggestions and useful references for the development of data analysis methods in dynamic centrifuge test and the insight of soil dynamic constitutive relation.