Vertical Compressive Stress Research Articles

Monoclinic distortion in strain relaxed [111] PbTiO3 epitaxial films

Stabilization of monoclinic distortion in [111]-oriented strained and strain-relaxed PbTiO3 epitaxial films are investigated using a phenomenological model. Under the effect of biaxial strain due to SrTiO3, temperature stability of monoclinic structure induced by vertical compressive stress is investigated. Due to relaxation of substrate constraint in-plane misfit of the epitaxial system changes from isotropic to anisotropic. Strain relaxation mediated formation of monoclinic structure, polarization, volume and shear strain, and dielectric and piezoelectric constants are investigated and compared with experimental data in the literature. For anisotropically strained [111] epitaxial films mechanical boundary conditions that facilitate enhancement of physical constants are explored.

Experimental Study and Failure Criterion Analysis of Rubber Fibre Reinforced Concrete under Biaxial Compression-Compression

In order to examine the biaxial compression-compression properties of rubber fibre reinforced concrete (RFRC), an experimental study on RFRC under different lateral compressive stresses was carried out by considering different rubber replacement rates and polypropylene fibre contents. The failure modes and mechanical property parameters of different RFRC working conditions were obtained from the experiment to explore the effects of rubber replacement rate and polypropylene fibre content on the biaxial compression-compression properties of RFRC. The following conclusions were drawn. Under the influence of lateral compressive stress, the biaxial compression-compression failure mode gradually developed from a columnar pattern to a flaky pattern, suggesting that the incorporation of rubber and polypropylene fibres into the concrete resulted in a significant change in the development of cracks. For different rubber replacement rates and polypropylene fibre contents, the vertical compressive stress exhibited the same developing trend under the influence of lateral compressive stress. Specifically, the lateral compressive stress imposed the minimum effect on the vertical compressive stress when the rubber replacement rate and polypropylene fibre content were 20% and 0.4%, respectively, and imposed the maximum effect when the rubber replacement rate and polypropylene fibre content were 20% and 0%, respectively. With the increase of rubber replacement rate, the vertical peak stress was significantly reduced, which implies that an appropriate amount of polypropylene fibres can increase the vertical peak stress to a certain extent. Then, the biaxial compression-compression mechanism of RFRC was analysed from the microscopic level by using scanning electron microscope (SEM). Meanwhile, based on Kupfer’s biaxial compression-compression failure criterion and the octahedral stress space, a biaxial compression-compression failure criterion for RFRC was proposed, which was proven to have good applicability. The research results of this study provide important theoretical basis for the engineering application and development of RFRC.

Local vertical compressive stress in the crane runway beam web

In this paper, the authors analysed several variants of connections between a block rail (60 mm × 60 mm) and a crane runway beam (IKS 800-6). They compared local vertical compressive stress in the crane runway beam web, calculated using an analytical approach and numerical simulations. In the case of the continuous block rail rigidly fixed to the beam flange, satisfactory convergence was obtained. For the remaining types of connections the results based on the analytical method were different from the results of the numerical simulations. The difference resulted from the fact that the analytical method did not take into account the crane rail joint. Furthermore, the impact of the elastomeric bearing pad on the local stress value was taken into account in a simplified manner in the analytical method by increasing the effective length by approximately 30%. The local vertical compressive stress in the crane runway beam web was significantly affected by the connection between the rail and the crane runway beam, the crane rail joint type, the use of the elastomeric bearing pad, the length of the elastomeric bearing pad, and the crane rail wear.

Physical properties and tensile strength evolution of gypsum materials under different water content conditions

To investigate the physical properties and tensile strength evolution of gypsum materials under different water content conditions, three groups of gypsum standard samples were prepared, including natural, saturated and dehydrated gypsum samples. Electron microscopy, composition analysis, Brazilian splitting tests and numerical simulation analysis were carried out. The results are as follows. The larger the water content of the samples is, the higher the content of CaSO4·2H2O, the more flocculation structures on the surface, and the higher the longitudinal wave propagation speed. Saturation and dehydration change the composition of the sample and cause a change in its tensile strength and failure mode. The fitting effect of the modified Hoek-Brown criterion is obviously better than that of the modified Mohr-Coulomb criterion because it considers the influence of uniaxial compressive strength. The Balmer criterion introduces the index b and greatly improves its regression accuracy. The vertical compressive stress exhibits a concentrated distribution. At x = 0, the peak value of the vertical load appears at the two ends of contact between the specimen and the indenter and gradually decreases from both ends to the centre. The horizontal stress is mainly tensile stress, and the value at x = 0 is the theoretical tensile strength. It is uniformly distributed on the line directly affected by the vertical load and decreases to both ends of the specimen along the line. It is reduced to 0 at the left and right ends. The horizontal deformation arises from both sides of the disk tip and then spreads downwards in an arc during loading. The horizontal strain in the upper part of the disk is always larger than that in the lower part. The upper part reaches its tensile strength and then fails due to the continuous loading.

Stretchable conductive-ink-based wrinkled triboelectric nanogenerators for mechanical energy harvesting and self-powered signal sensing

The rapid development of flexible electronics and the corresponding fabrication technologies have increased the use of portable and wearable self-powered devices. In this work, a shape-adaptive flexible triboelectric nanogenerator (TENG) based on a conductive ink material is demonstrated. The conductive ink-based bottom electrode with wrinkled structure ensures that the TENG exhibits outstanding stretchability and output performance such that it can adapt to complex and varying environmental factors. An output voltage of 128 V and power density of 0.286 mW/cm2 were generated under contact mode with applied vertical compressive stress of 20 N. Furthermore, because of the intrinsic mechanical ductility of the wrinkled structure, the proposed TENG can maintain excellent output performance when deformed under a certain range of strains, and active motion monitoring and energy harvesting functions can also be stably achieved on the irregular surface. The device was combined with a wireless transmission system to form a wearable mechanical signal detection patch for real-time monitoring of human joint activity, which provides a new treatment option in the field of sports rehabilitation. These advantages demonstrate that the proposed cost-effective and portable TENG is a promising candidate for the development of a self-powered strain sensing device in future practical applications.

Mechanical properties of multi-recycled aggregate concrete under combined compression-shear loading

The mechanical properties and strength failure criteria of multi-recycled aggregate concrete (multi-RAC) under combined compression and shear loading states are investigated in this paper. The peak shear strength, peak shear displacement, and failure patterns are compared under different regeneration cycles and normal compressive stress ratios. The results reveal that both the peak shear strength and peak shear displacement increase with the increased normal stress ratio. The shear failure pattern with higher severity corresponds to more spalling powder and debris deposited on the shear fracture surface. When the regeneration cycles of coarse aggregate increase, the peak shear strength decreases and the descending trend become more evident with the higher vertical compressive stress ratio. Under the normal compressive stress, contact friction strength is the dominant component of peak shear strength among the cohesive strength, contact friction strength, and shear dilation strength. Based on different stress expressions, three compression-shear failure criterion models considering the regeneration cycles of coarse aggregate under planar stress state were established for RAC. The stress invariance failure criterion model and octahedral stress failure criterion model in quadratic parabolic functional form can provide high prediction accuracies.

Influence of the attenuation of subgrade elastic modulus caused by precipitation on ballasted track structure

• Developed numerical model of ballasted track-subgrade structure considering precipitation based on FEM/EMLT. • Quantitatively revealed the influence of the subgrade elastic modulus for ballasted track-subgrade structure. • Systematically presented latest materials to improve subgrade waterproofing and drainage performance. Precipitation will cause subgrade elastic modulus ( E s ) to decay as subgrade are composed of fine-grained soil with water sensitivity, resulting in adverse mechanical effects on the ballasted track structure. A numerical model of the ballasted track-subgrade structure was established using the KENTRACK program combining the finite element method (FEM) and elastic multi-layer theory (EMLT), taking into account the non-linearity of the ballast and sub-ballast. The reliability of the developed numerical model was verified macroscopically by a laboratory testing based on vertical compressive stress distribution at the top of subgrade. The mechanical response of the track-subgrade structure and the damage law of the subgrade based on permanent deformation were quantitatively analyzed due to the attenuation of E s . The latest materials for the selection to improve subgrade waterproofing and drainage performance were more systematically presented. The results show that the subgrade surface occurs the stress concentration phenomenon as E s becomes larger, and the subgrade elastic deformation is not sensitive to E s with increasing it to 80 MPa, which the impact mainly appears in the region surrounded by two-axle load and the two rails. In addition, E s decay due to precipitation under constant applied load conditions directly reduces the service life of the subgrade, and the relationship between the allowable number of load repetitions ( N a ) at the top of subgrade and E s can be expressed as a power function. The laying of wicking geotextiles at the top of subgrade, asphalt mixture/PP-modified gravel mixture waterproofing layer, etc. can be utilized to improve the elastic modulus of subgrade due to their excellent waterproofing and drainage performance.

Experimental Study on Interface Model of Asphalt Pavement under Vertical Load

Layered asphalt pavement makes the interlayer contact more complicated. In order to further understand the characteristics of interlayer interface of asphalt pavement under vehicle load, this paper analyzes the change rule of interlayer interface of asphalt pavement under a vertical load condition, based on the Goodman model. According to the characteristics of asphalt pavement, the experiment temperature, gradation, amount of viscosity-level oil, type of viscosity-level oil, and vertical compressive stress are taken as parameters, and the universal testing machine (UTM) and self-modified test fixture are used to carry out the direct interlayer shear test. Experimental results show that the vertical load has a significant effect on the characteristics of the interlayer interface. With an increase in the vertical load, the maximum bonding coefficient changes greatly. Additionally, when the vertical load is constant, the temperature and spreading amount of viscosity-level oil have a strong influence on the interlayer bonding state. With an increase in temperature, the maximum bonding coefficient decreases. The adhesion coefficient increases first and then decreases with increasing spreading amount. The best spreading amounts of oil between the upper and middle layers, the middle and lower layers, and the lower layer and cement-stabilized base layer under different vertical load conditions are recommended. This study offers important guidance for designing pavement structure.

Strengthening Shear Resistance of Beams without Web Reinforcements Using Vertical Prestressed Steel Bars

Ensuring the shear capacity of concrete structures is crucial. The vertical prestressed steel bar (VPSB) strengthening method is effective for improving the shear behaviour of concrete structures. Four concrete beams are investigated to reveal the effect of VPSBs on the shear capacity of concrete beams without web reinforcement. Test results indicate that the shear capacity of the test beam strengthened by VPSBs in the beam is significantly increased by more than 95%, and the failure mode of the test beam changes from diagonal tension failure to shear compression failure. Additionally, the results provide insights into the strengthening mechanism of VPSBs, i.e., the shear contribution of the VPSBs can be categorised into two stages. The vertical compressive stress provides shear contribution in the first stage and provides control in terms of crack development; meanwhile, in the second stage, the stirrup action by VPSBs contributes to shear.

Influence of Axle Load and Asphalt Layer Thickness on Dynamic Response of Asphalt Pavement

Based on the test data of vehicle load test on asphalt pavement, the significance of dynamic response index of different asphalt pavement to axle load change of single and double rear axle trucks is analyzed. The changes of horizontal strain at the bottom of asphalt layer, vertical compressive stress at the top of subgrade, and vertical displacement of transition layer and bottom compressive stress before and after laying of middle and upper layers are revealed. The test results show that reducing the thickness of asphalt layer or increasing the vehicle axle load can lead to the more unfavorable stress-strain distribution in asphalt pavement under driving load. The influence of the fluctuation of truck axle load or asphalt layer thickness on the stress-strain distribution in asphalt pavement varies with the type of pavement structure, pavement response index, vehicle driving speed, vehicle type, and the horizon of the measuring point. The transverse strain at the bottom of the asphalt layer is more affected by the axle load and the thickness of the asphalt layer than the longitudinal strain at the bottom of the asphalt layer. The measured value of the dynamic response index of the semirigid asphalt pavement is more affected by the axle load than that of the inverted asphalt pavement. However, the measured value of the dynamic response index of the semi-rigid asphalt pavement is less affected by the thickness of the asphalt layer when the thickness of the asphalt layer changes within a certain range. The tensile strain part of the longitudinal strain at the bottom of the asphalt layer and the compressive strain part of the transverse strain at the bottom of the asphalt layer are greatly affected by the thickness of the asphalt layer. The sensitivity of fatigue life of asphalt pavement of inverted structure to driving speed and axle load is less than that of semirigid structure. The research results can provide reference for the analysis of the asphalt pavement disease mechanism and provide guidance for asphalt pavement structural design and service life analysis.

Numerical analysis of dynamic behavior of Bi-block precast asphalt trackbed for High-Speed railway

In this paper, asphalt trackbed, including the dry-wet hybrid rubberized asphalt mixture (D-WHRAM) trackbed and dry-mixed rubberized epoxy asphalt mixture (DREAM) trackbed, has been proposed. The dynamic response and the design parameters of the proposed trackbed were evaluated by numerical analysis. A three-dimensional finite element model of the bi-block precast asphalt trackbed was developed using the ABAQUS software. The thickness and width of the prepared asphalt mixture cuboid (PAMC) were set as 25 – 40 cm and 85 – 100 cm, respectively. Then, the effects of thickness and width on the structure performance were analyzed according to the dynamic response, including vertical dynamic compressive stress, deformation, acceleration collected from the top of the PAMC, the tensile strain collected from the bottom of the PAMC, and the evolution mechanism of the vertical dynamic compressive stress within the whole subgrade. The results showed that the suitably designed parameters of PAMC for two types of asphalt trackbed were 35 cm in thickness and 100 cm in width. Although the material compositions of the two types of the asphalt trackbed are remarkable, the maximum values of compressive stress on the top of PAMCs were about the same. However, the DREAM trackbed shows a larger dynamic deformation than the D-WHRAM trackbed due to the greater crumb rubber content.

Закономерности формирования напряженного состояния горных пород в кровле выработанного пространства при его развитии

Formation of the stress-and-strain state of the rock mass in the roof of mined coal seam depends on the development of the mined-out space. It is believed that the coal seam is located deep enough and it can be assumed that the effect of the daylight surface on its condition can be neglected. In this case, the solution is based on the analytical approach using methods of the complex variable theory and it is reduced to the construction of a single permission analytical function. The paper reviews the evolution of the deformation processes in development of the mined-out space in presence of a hard-to-collapse elastic roof, which is capable of sinking smoothly over time, without sudden caving on the landings on the floor. A particular attention is paid to the phase when the roof and the floor touch each other, i.e. the roof caving, starting from the first touching and up to its complete caving. In this case, two sections of the hanging roof are formed, that are gradually reducing in length as the dimensions of the mined-out space increase. The area of roof caving is progressively increasing, and the vertical compressive stresses at the boundary are gradually rising, tending to reach the initial vertical pressure at the depth of the formation before the start of its mining. Tension zones relative to the horizontal and vertical stresses are identified, that are attributed to the areas of roof hang-up, which may determine the location of zones with higher methane and formation water permeability, both in the rocks between the seams and in the coal seam.

Investigation of conventional and asphaltic underlayment track behaviors subjected to freight train load: Mechanistic approach

The load characteristics in terms of the carrying capacity and the train operation speed limit Indonesia's conventional track capability. In this study, the behaviors of Indonesia's conventional tracks and the proposed asphaltic underlayment tracks under cyclic loading conditions of the low-speed Babaranjang (long-chain coal) freight trains have been evaluated using the finite element package Abaqus/CAE considering linear elastic behavior of materials. The numerical modeling was applied on three different layer thicknesses of sub-ballast in Indonesia's conventional tracks and three different layer thicknesses of asphalt in asphaltic underlayment tracks to investigate the vertical compressive stress, horizontal-vertical-maximum strain, and deformation behaviors. According to the numerical simulation, the measurements indicate that the asphaltic underlayment tracks are superior to Indonesia's conventional tracks. Furthermore, a 15 cm of asphalt layer in the asphaltic underlayment tracks demonstrates promising performance in the future of Indonesia's railway systems. The asphaltic underlayment tracks are expected to serve the heavier and higher speed Babaranjang freight trains with longer service life and lower life cycle cost than Indonesia's conventional tracks.

Dike Propagation During Global Contraction: Making Sense of Conflicting Stress Histories on Mercury

Thrust fault-related landforms, smooth plains units, and impact craters and basins have all been observed on the surface of Mercury. While tectonic landforms point to a long-lived history of global cooling and contraction, smooth plains units have been inferred to represent more punctuated periods of effusive volcanism. The timings of these processes are inferred through impact cratering records to have overlapped, yet the stress regimes implied by the processes are contradictory. Effusive volcanism on Mercury is believed to have produced flood basalts through dikes, the propagation of which is dependent on being able to open and fill vertical tensile cracks when horizontal stresses are small. On the contrary, thrust faults propagate when at least one horizontal stress is very large relative to the vertical compressive stress. We made sense of conflicting stress regimes through modeling with frictional faulting theory and Earth analogue work. Frictional faulting theory equations predict that the minimum and maximum principal stresses have a predictable relationship when thrust faulting is observed. The Griffith Criterion and Kirsch equations similarly predict a relationship between these stresses when tensile fractures are observed. Together, both sets of equations limit the range of stresses possible when dikes and thrusts are observed and permitted us to calculate deviatoric stresses for regions of Earth and Mercury. Deviatoric stress was applied to test a physical model for dike propagation distance in the horizontally compressive stress regime of the Columbia River Flood Basalt Province, an Earth analogue for Borealis Planitia, the northern smooth plains, of Mercury. By confirming that dike propagation distances from sources observed in the province can be generated with the physical model, we confidently apply the model to confirm that dikes on Mercury can propagate in a horizontally compressive stress regime and calculate the depth to the source for the plains materials. Results imply that dikes could travel from ∼89 km depth to bring material from deep within the lithosphere to the surface, and that Mercury’s lithosphere is mechanically layered, with only the uppermost layer being weak.

Effect of Geo-Grid Depth in Roads Cross-Section on Reducing Pavement Rutting

Pavement structures cover vast areas of urban cities and non-urban roads and play a key role in daily commuting functionality and economic development; therefore, they must be conserved against any distress. The rutting problem, being a major distress to the pavement structure, must be solved and dealt with in order to preserve its value. One way of solving this dilemma is by using geo-grids within the pavement structure. A geo-grid is a synthetic material usually made from polymers with different thicknesses and stiffnesses. This paper investigates the effects of geo-grids on reducing the rutting occurrence through adding a layer of geo-grid with certain properties at different levels of the pavement structure. We also investigate, the result of the added geo-grid material to the developed vertical stresses within the pavement cross-section. This investigation is conducted by constructing a 3-D finite elements-based (FE) model of a pavement cross-section using ANSYS software; student version R1 2021. The FE-based model is validated by comparing its numerical predictions with the experimental results acquired from an accelerated large-scale paved model. The results show that the deeper the geo-grid is positioned, the more significant the rutting resistance is observed due to the stiffness of the geo-grid bearing the tensile force until a certain depth. Moreover, noticeable stress reduction is seen in the developed vertical compressive stresses below the loading area resisted by the geo-grid.

Mechanical Performance of Confined Autoclaved Fly-Ash-Brick Masonry Walls under Cyclic Loading

In order to solve the limitations of masonry structures, such as poor seismic performance, complicated construction techniques, and energy wastage of wall materials, a new type of confined autoclaved fly-ash-brick wall was proposed and its mechanical performance was analyzed. An axial compression test of autoclaved fly-ash-brick short columns was carried out to analyze the failure mode and obtain the constitutive parameters of the brick. Meanwhile, a low-cyclic loading test of an assembly using an autoclaved fly-ash-brick wall was carried out to prove the correctness of the numerical model. Under multiple influencing parameters, the seismic performance of the assembly of autoclaved fly-ash-brick walls was analyzed by a numerical-simulation method. The results show that (1) the seismic performance of the assembled autoclaved fly-ash-brick walls is better than that of cast-in-place masonry walls; (2) low-strength mortar leads to premature cracking, which is unfavorable to earthquake resistance of the walls; and (3) the bearing capacity of the wall is increased and then decreased with the increase of the vertical compressive stress, so the number of layers of brick masonry structural should be limited. In addition, some construction measures were proposed to improve the mechanical performance of assembled autoclaved fly-ash-brick walls.

Dynamic performance and seismic damage analysis of an ancient masonry pagoda

ABSTRACT To study the dynamic characteristics and seismic damage of the Bayun Pagoda,the dynamic characteristics are determined via an in-situ dynamic test, and the flexibility curvature method is used to identify the damage. Moreover, the numerical calculation results of the dynamic characteristics are compared with the test results. The mechanical parameters of the materials are determined in the consistency of the dynamic characteristics, and a plastic damage model is also introduced. From the vertical compressive stress the initial damage is defined, and the seismic damage is analyzed by inputting El-Centro, Taft, and Lanzhou artificial wave. As results, the first-order natural frequencies are close to each other in the horizontal East-West and North-South directions, and the initial damage rates of the 6th, 8th, 10th floors are higher. The distributions of the principal tensile stress excited by different seismic are similarbut the distributions of seismic damage are slightly different; the area with serious seismic damage is in the middle and bottom floors, and the damage accumulation of the first floor is more obvious than those of the other floors. Moreover, the outer edge of each floor, the pagoda eaves, and the periphery of the archway are found to be easily damaged.

Tectono-magmatogenering structures in zones of increased geodynamic instability as priority objects for exploration of hydrogen fields

Based on comparison of the migration activity of hydrocarbons, helium and hydrogen, the paper substantiates the types of cap rocks for hydrogen accumulations (pools), which most of all contributes to its partial shieldingat steady feed. Such cap rocks are represented by predominantly smectite clay, pure (without inclusions) salt at depths over 1—2 km, non-fractured quartz sandstone at depths over 4 km, effusive and hypabissal intrusive rocks, as well as basement rocks undisturbed by metamorphic decomposition processes. Endogenous hydrogen isconsidered as the main factor of dissipative structures formation. Occurrence of hydrogen, hydrocarbon and ore macro accumulations is a kind of energy, information-geochemical fluctuations, which are intermediate states of dissipative structures subordinated to the planetary heat and mass transfer processes caused by the deep Earth degassing. In this context, the nature of geodynamic instability (activation of vertical movements, shifts, tensile and compressive stresses) can be considered as a growing sequence of dissipative processes associated with the energy percolation role of endogenous hydrogen. In the hierarchy of ring structures (RS) (from minor depressions to large structures of dozens kilometres in diameter) special attention should be paid to Sribne RS within the Dnieper-Donets Basin and Kaluga RS within the SW part of the Voronezh anteclisepericline. These ring structuresare genetically related to explosion or volcanic calderas, and characterized by ancient origin (Proterozoic) and long-term development, including neo- and actuotectonic stages. Intensity of hydrogen degassing in the Sribne RSis confirmed by micro- and nano-inclusions in the black-shale domanicoid rocks of the productive horizons in the form of particles of native metals(including oxyphile elements Al, Zn, W and others), natural alloys and intermetallids, which are tracers of ascending flows of deep reduced fluids. It is reasonable to assume the occurrence of a large hydrogen or helium-hydrogen field (group of fields) within the Sribne RS in the Lower Visean, Lower Bashkirian and Lower Permian aged rocks, which are shielded by the Lower Permian salt deposits.

In-Plane Behaviour of Masonry Walls: Numerical Analysis and Design Formulations.

This paper presents the results of several numerical analyses aimed at investigating the in-plane resistance of masonry walls by means of two modelling approaches: a finite element model (FEM) and a discrete macro-element model (DMEM). Non-linear analyses are developed, in both cases, by changing the mechanical properties of masonry (compressive and tensile strengths, fracture energy in compression and tension, shear strength) and the value of the vertical compression stress applied on the walls. The reliability of both numerical models is firstly checked by means of comparisons with experimental tests available in the literature. The analyses show that the numerical results provided by the two modelling approaches are in good agreement, in terms of both failure loads and modes, while some differences are observed in their load-displacement curves, especially in the non-linear field. Finally, the numerical in-plane resistances are compared with the theoretical formulations provided by the Italian building code for both flexural and shear failure modes and an amendment for the shape factor ‘b’ introduced in the code formulation for squat walls is proposed.

An investigation on the deterioration of physical and mechanical properties of granite after cyclic thermal shock

As one of the main thermal storage medium of hot dry rock geothermal resources, granite is often subject to frequent thermal shock during the geothermal exploitation. Grasping the response regularity of granite to thermal shock is of great significance to the construction and long-term reliability evaluation of enhanced geothermal system (EGS). This paper investigated the physical and mechanical properties of granite after 0∼20 thermal shocks, and discussed its internal deterioration mechanism. Combined with ANSYS numerical simulation analysis, the mechanical formation mechanism of thermal cracks that lead to the deterioration of physical and mechanical properties of granite was analyzed. The results show that the first thermal shock tends to cause the severest deterioration to both physical and mechanical properties of granite. But when the number of thermal shocks exceeds 10, the deterioration slows down. The increase in contact thermal resistance between mineral particles after cyclic thermal shock results in a decrease in the thermal conductivity of granite. The enhancement of local stress concentration effect and the increase of local bearing capacity difference of granite after cyclic thermal shock result in the decrease of peak strength and the enhancement of ductility characteristics of granite. Due to the existence of thermal cracks, the granite after cyclic thermal shock has one more path to release the energy stored during the loading process than the natural granite. Therefore, the maximum counts at the beginning of crack propagation and the entire crack propagation stage are smaller than that of the natural granite. During the thermal shock, the huge instantaneous temperature difference between the interior and exterior of granite leads to the formation of thermal stress, which increases rapidly and then disappears gradually. As a result, the interior of granite mainly bears the effect of the vertical compressive thermal stress up to 7.59 MPa, while the exterior of granite mainly bears the effect of vertical tensile thermal stress up to 9.18 MPa. The propagation of some pre-existing micro cracks with proper orientation in the interior of granite and the initiation and propagation of secondary thermal cracks on granite surface are identified as two main causes to the deterioration of the physical and mechanical properties of granite after cyclic thermal shock.