The permeability of rock mass is closely related to the stability and safety of underground structure, especially in underground water-sealed storage caverns. With regard to the estimation approaches in predicting the hydraulic conductivity of fractured granite in water-sealed storage caverns, there are some limitations of parameter selection leading to poor applicability. Focusing on the contribution

In this study, the X5 KCC in Shiquan Coal Mine was investigated by means of controlled source audio magnetotelluric exploration and borehole television. In this way, the subsection geological structure of the KCC was obtained. Next, the geological and electrical characteristics of each part were analyzed, and it is concluded that the development status of the mud part under coal seam floor is the key

As the energy consumption of residential building takes a large part in the building energy consumption, it is important to promote energy efficiency in residential building for green development. In order to evaluate the energy consumption of residential building more effectively, this paper proposes a combined prediction model based on random forest and BP neural network (RF-BPNN). To verify the

The total organic carbon content (TOC) is a core indicator for shale gas reservoir evaluations. Machine learning-based models can quickly and accurately predict TOC, which is of great significance for the production of shale gas. Based on conventional logs, the measured TOC values, and other data of 9 typical wells in the Jiaoshiba area of the Sichuan Basin, this paper performed a Bayesian linear regression

Strain rate is not only an important influence factor for deformation property but also an important parameter for analyzing the dynamic mechanical behavior of rock material. In this study, the dynamic compressive mechanical properties of saturated yellow sandstone at four strain rates and six freeze-thaw temperatures are investigated by using the SHPB test system. The coupling effect of strain rate

The evaluation and prediction of favorable coalbed methane (CBM) sweet spot play an important role in well location deployment and recovery prediction in CBM blocks. This work investigates the CBM geology and accumulation characteristics of No. () coal in the Carboniferous Taiyuan Formation in Yangjiapo block based on data from 14 CBM wells. The desorption index is proposed to be used to study the

This paper reports the dewatering scheme of a deep excavation in sandy pebble strata. The excavation is in high permeability strata and is close to the Yellow River, making the dewatering difficult during construction. At present, few researchers have specially studied the dewatering scheme of deep excavations in strong permeable strata near the water resource. Field pumping test was conducted before

Fracability evaluation is the basis of reservoir fracturing and fracturing zone optimization. The tight sandstone reservoir is characterized by low porosity and low permeability, which requires hydraulic fracturing to improve industrial productivity. In this study, a systematic model was proposed for the fracability evaluation of tight sandstone reservoirs. The rock mechanics tests and sonic tests

The shale gas productivity model based on shale gas nonlinear seepage mechanism is an effective way to reasonably predict productivity. The incomplete gas nonlinear effects considered in the current production prediction models can lead to inaccurate production prediction. Based on the conventional five-zone compound flow model, comprehensive gas nonlinearities were considered in the improved compound

The complex and heterogeneous pore structure and oil content of lacustrine shales introduce significant challenges in the exploration of shale petroleum systems. To further expand our geological understanding of lacustrine shales and provide guidance for hydrocarbon exploration, in this study, based on programmed and improved Rock-Eval pyrolysis, total organic content (TOC) measurements, scanning electron

To the accurate reconstruction of the hydrocarbon generation history in the Dongying Depression, Bohai Bay Basin, East China, core samples of the Eocene Shahejie Formation from 3 shale oil boreholes were analyzed using organic petrology and organic geochemistry methods. The shales are enriched in organic matter with good to excellent hydrocarbon generation potential. The maturity indicated by measured

Carbonate reservoirs in the South China Sea mostly contain natural fractures with various length scales and different intensities, which causes great challenges in efficient reservoir modeling and flow simulation. Existing efforts based on dual-porosity and dual-permeability models could not reflect the characteristics of production data in certain wells. To accurately and efficiently characterize

Diffusion radius is an important construction parameter, because it can significantly influence the grouting effectiveness. Theoretical models in predicting diffusion radius have been practiced, but there are still significant discrepancies between theoretical calculations and realistic results in the practical construction. One of the critical reasons for the misprediction is the time-dependent behavior

Thermal properties are important for featuring the water-heat transfer capacity of soil. They are also key to many processes in earth sciences, such as the land surface processes and ecological and geoenvironmental dynamics and their changes in permafrost regions. With loose and porous structures, the organic matter layer in soil strata substantially influences soil thermal conductivity. So far, thermal

The production of a low permeability reservoir decreases rapidly by depletion development, and it needs to supplement formation energy to obtain stable production. Common energy supplement methods include water injection and gas injection. Nitrogen injection is an economic and effective development method for specific reservoir types. In order to study the feasibility and reasonable injection parameters

The pore ratio is an important parameter affecting the stability and safety of tailings reservoirs; however, the relationship between the pore ratio and physical properties of tailings sand has not been researched in-depth. In this paper, using the tailings from a tungsten mine in southern Shaanxi as a case study, the correlation between the minimum void ratio and related parameters is analyzed, based

To study the rock mechanical behaviors and damage process mechanism of granite samples under triaxial stress, conventional triaxial compression tests were carried out on an RMT-150B rock mechanics testing machine and acoustic emission detector. The test results show that the strength of the granite sample has a good linear relationship with the confining pressure, the cohesion force of the granite

The eastern Tianshan metallogenic belt is an important molybdenum resource base in Xinjiang and is characterized by large-scale porphyry Mo deposits formed during the Triassic. The Tieling Cu-Mo porphyry deposit, which is situated in the western part of the eastern Tianshan metallogenic belt, was recently recognized as being related to Carboniferous granite porphyry. Three stages of hydrothermal mineralization

This paper investigates the loading behavior and soil-structure interaction associated with a floating stone column under rigid foundation by using the discrete element method (DEM). The aggregates and soft soil are simulated by particles with different sizes. The rigid foundation is simulated by two loading plates at the same position with the same velocity. The stress distributions and microscopic

The effectiveness of the use of waste fly ash (FA) and cement (OPC) in the stabilization of subgrade soils and the reasons likely to influence the degree of stabilization were investigated. Incorporating waste fly ash (FA) and cement (OPC) as additives leads to significant environmental and economic contributions to soil stabilization. This study involves laboratory tests to obtain the Atterberg limit

Marine corrosion and freeze-thaw environment will bring serious damage to marine concrete structures, leading to affect the safety and service life of structures. With the help of artificial climate and environment simulation laboratory, the variation of the compression strength and elastic modulus of concrete with the number of freeze-thaw cycles and corrosion time under the corrosion and freeze-thaw

In recent years, greenhouse gases have increased in the atmosphere, and climate change concerns have triggered global efforts to find solutions for CO2 capture, separation, transport, and storage. Geological sequestration in the depleted unconventional reservoir is an effective measure to reduce the atmosphere’s CO2 content. The exact evaluation of the CO2 storage capacity can verify the feasibility

Dust is one of the main pollutants in coal mines, which seriously affects the physical and mental health of workers, as well as the safe production in underground mines. Dual-radial swirl shielding ventilation is a new ventilation method for a fully mechanized excavation face and can effectively reduce the dust concentration in the underground. The dust control effect of dual-radial swirl shielding

The Park-Paulino-Roesler (PPR) cohesive zone model (CZM) for coal was established for analyzing mixed-mode I/II fractures using semicircular specimens under punch-through shear (PTS) and three-point bending (SCB) tests. In these methods, the main parameters of the fracture were obtained through SCB tests and PTS tests. And according to the experimental results, the coal specimens show obvious characteristics

Conventional heavy oil has abundant reserves and low recovery efficiency in offshore oilfields. Autogenous heat technology uses 2-3 kinds of inorganic salt solution to produce inert gas and release a lot of heat under the action of a catalyst. It is applied to improve heavy oil recovery of the offshore oilfield. This paper applies experimental schemes such as viscosity reduction rate evaluation, heat

Due to the limitation of geological conditions and route alignment, tunnel engineering will inevitably pass through special sections such as shallow buried section, broken rock layer, and loss and weak rock stratum. Tunnel construction in these special sections will easily lead to tunnel collapse, landslide of portal slope, excessive deformation of supporting structure, and even deformation and damage

With the reduction and depletion of shallow energy, the mining depth of coal around the world is increasing year by year, and the mining depth of some coal mines in China has reached kilometers. The main roadway near the goaf with the deep high static stress is very easy to be damaged after being disturbed by the mine earthquake. Taking the main roadway in the no. 1 mining area of Gaojiapu coal mine

This paper focuses on the stability of the high-level radioactive waste (HLW) in the proposed clay rock in Tamusu area of China. The in-situ stress as well as the variational characteristics of ambient temperature caused by nuclide decay during HLW storage should be noticeable. A series of thermal property tests and thermo-mechanical coupled strength (T-M) tests of rock samples in the target formation

The Permian tight clastic reservoir and Ordovician carbonate reservoir were developed in the central-southern Ordos Basin. This study investigated the fluid inclusion petrography, diagenetic fluid characteristics, formation process of natural gas reservoir, source rock characteristics, and reservoir accumulation characteristics of these Paleozoic strata by petrographic observations, scanning electron

In the study of sequence stratigraphy in continental rift basins, the use of seismic data to track different levels of sequence stratigraphic boundaries laterally is the key to the division of sequence stratigraphic units at all levels and the establishment of an isochronous sequence stratigraphic framework. Traditional seismic interpretation and the establishment of a 3D sequence stratigraphic structure

Loess cave dwellings are the most typical style of regional architecture in northwest China; now, there are still tens of millions of people living in them. The northwest is an earthquake-prone area, and cave dwellings have suffered a lot of damage in previous moderate and strong earthquakes, so their earthquake resistance has attracted people’s attention. At present, the seismic analysis of aboveground

Coal mining enterprises have a variety of water sources, complex drainage structures, long production chain, and many links, which lead to uncoordinated water utilization and low water efficiency. Taking a large coal mining area of China as an example, a dynamic model was established to evaluate the water utilization efficiency based on the Life Cycle Sustainability Assessment (LCSA) theory. In the

Production stimulation techniques such as the combination of hydraulic fracturing and lateral drilling have made exploiting unconventional formations economically feasible. Advancements in production aspects are not always in lockstep with our ability to predict and model the extent of a fracturing job. Shale is a clastic sedimentary rock composed of a complex mineralogy of clay, quartz, calcite, and

In this study, physical experiments, clay mineral determination, and pH testing were performed to examine the basic properties of soil samples from a soil material yard selected for dam construction at Hua’ao Lake, Qian’an County, Jilin Province, China. The results show that the soil in the study area is cohesive, the mineral content of illite in the illite/montmorillonite mixed layer is approximately

With low porosity and low permeability, shale reservoirs cannot be mined economically without large-scale hydraulic fracturing operation. However, abundant fracturing fluid will enter the reservoirs during the process of fracture. Nevertheless, there have not been specific research findings on the imbibition law of Fuling shale gas reservoir in China. In this study, an imbibition experiment was carried

Montmorillonite is the main mineral source for the swelling and shrinking of expansive soils. The macroscopic phenomena of soil are affected by the action of deep-level nanosized minerals. In order to illustrate the nanoscale mechanism from the molecular level, a combination of Monte Carlo and molecular dynamics was used to explore the swelling and shrinking characteristics of montmorillonite. The

In order to study the mechanical properties of granite at the micro- and nanoscale, the load-displacement curve, residual indentation information, and component information of the quartz, feldspar, and mica in granite were obtained using a nanoindentation test, a scanning electron microscope (SEM), and X-ray diffraction (XRD). The elastic modulus and the hardness of each component of the granite were

Through field observation and theoretical study, we found that the Hanxing mining area has a typical ternary structure in coal mining under high water pressure of the aquifer. This ternary structure is the Ordovician limestone aquifer-aquiclude including thin limestones-coal seam. Although the aquiclude is considerably thick, there is still a great risk of water burst during mining under water pressure

A novel numerical experimental method is developed herein to study frost-heaving cracking in fractured rock masses by reproducing the physical experimental frost-heaving process. The failure mode of a preexisting closed and water-saturated single-flaw in a rock mass during the frost-heaving process is affected by the inclination angle, flaw width, crack length, and cooling rate. Additionally, a regression

This study is aimed at better understanding the deformation and failure mechanism of surrounding rock during excavation unloading of a high-stress rock mass and determining the reasonable reinforcement time for the surrounding rock. To fulfill this aim, true triaxial tests were carried out on different loading and unloading paths during the unilateral unloading of a high-stress rock mass. The variational

The influence of low temperature on longitudinal wave velocity, uniaxial compression strength, tensile strength, peak strain, secant modulus, and acoustic emission characteristics of yellow sandstones was studied. The results show that the secant modulus increases with decreasing temperature when the axial strain is less than 0.6%, and a contrary influence performs for the subsequent stage due to the

In recent years, the studies on fine-grained sedimentation mainly focus on the rock type, sedimentary environment, sedimentation, and sequence stratigraphy, while those on the relationship between sedimentary environment and lithofacies development are rare. However, a clear understanding on the relationship is of great significance to the muddy shale oil and gas exploration. This paper studied the

The durability of the concrete structure under the coupling effect of underwater corrosion particles has always been one of the hot issues at home and abroad. Aiming at the damage problem of the underground concrete structure in a marine and offshore chloride corrosion environment, based on the pile foundation engineering of the Coastal Industrial Park, the corrosion resistance test of pile foundation

To describe the fracture width is crucial for the flow conductivity evaluation, which influences the exploitation efficiency of unconventional oil and gas resources. Commonly, as the proppants fill in the fracture, the deformation will happen under the closure pressure to resist the fracture width change. Therefore, it is significant to develop the theoretical model to predict the variation. In this

In order to grasp the characteristics and mechanism of saline soil deformation under the coupling action of cooling and dynamic load, three types of subgrade fillings from the Qarhan-Golmud Highway in Qinghai-Tibet Plateau were selected as experimental soil samples for the experimental study. Firstly, the freezing temperature experiment was carried out on SS (sandy silt) and HS (high-sulfate silty

The Lower Silurian Longmaxi Formation in the southern Sichuan Basin is composed of a series of dark carbonaceous shales deposited in a hydrostatic shelf reduction environment. In this study, the ratio of uranium to thorium (U/Th), the total organic carbon (TOC), and the biological silicon content (SiBio) were selected as the characteristic parameters to precisely analyze the sedimentary environment

The shear behavior of saturated loess was examined by performing a series of ring shear tests with different shearing rates. The effects of shearing rates on the shear behavior of saturated loess with different normal stress are presented and discussed. The results showed that peak shear strength and steady-state shear strength were greater when the shearing rate was low and vice versa. Compared with

To investigate the creep mechanical characteristics of rocks in different saturated states after freeze-thaw cycles, samples with different saturations (30%, 50%, 70%, 90%, and 100%) were selected for nuclear magnetic resonance (NMR), scanning electron microscopy (SEM), and uniaxial compression creep tests. The internal microscopic damage of the rock sample and mechanical characteristics under long-term

In this research, neural network models were used to predict the action of sloshing phenomena in a tank containing fluid under harmonic excitation. A new methodology is proposed in this analysis to test and simulate fluid sloshing behavior in the tank. The sloshing behavior was first modeled using the smooth particle hydrodynamics (SPH) method. The backpropagation of the error algorithm was then used

Shallow landslides are among the natural threats causing death and damage. They are mostly triggered by rainfall in mountainous areas where precipitation used to be abundant. The amount of rainfall inducing this natural threat differs from one site to another based on the geographical characteristics of that area. In addition to the rainfall depth, the determination of soil water content in a specific

Determining the pore structure characteristics and influencing factors of continental shale reservoir in the oil generation stage is of great significance for evaluating the shale oil reservoir space and analyzing shale oil enrichment mechanism. In this paper, shale from the first member of the Upper Cretaceous Qingshankou Formation (K2qn1) in the Songliao Basin was selected. X-ray diffraction (XRD)

Controlling settlement and earth pressure behind retaining wall in soft soil area are ongoing practical problems for the construction and operation of highway, which are mainly caused by the poor nature of soft soil. To reduce the pushing force on retaining wall and subgrade settlement, the authors propose the use of lightweight foamed concrete as subgrade filler behind the buttressed earth-retaining

Based on the dynamic expressions of permeability and porosity of the coal seam derived in the paper, a multiphysical field coupling numerical model of gas migration under the interaction of stress field and seepage field was established. The gas drainage project #3 Coal Seam operated by Sima Coal Industry Co., Ltd., was selected as the study object. Taking different drainage time periods in various

A development of overlying strata fractures and an unknown distribution of the two zones, which results from a strong shock tendency roof short-distance coal seam group mining, are the main problems faced by Xiashijie Coal Mine. Consequently, an experiment has been conducted; here are the steps: designing an underlying strata development law and the two-zone distribution physical similarity simulation

The ageing disintegration, the damage, and failure mechanism of water-saturated soft rock are of significance to hazard prevention for deep mining. In this paper, indoor experiments, including disintegration behaviour tests in water, uniaxial compression failure tests of rock samples with different water contents, and variations in the microstructure of mudstone under saturated water contents, were

Finding ways to accelerate the effective development of tight sandstone gas reservoirs holds great strategic importance in regard to the improvement of consumption pattern of world energy. The pores and throats of the tight sandstone gas reservoir are small with abundant interstitial materials. Moreover, the mechanism of gas flow is highly complex. This paper is based on the research of a typical tight

In oilfield development, the pore pressure difference between adjacent areas leads to cracks and slipping in the weak structural surface layer, which triggers the shear failure of the casing. The formation slip involves a large range of formation, and its amount is not proportional to the size of the slipping rock mass, which conventional physical models cannot simulate. In this study, based on the

This paper presents a stochastic analysis method for linear elastic fracture mechanics using the Monte Carlo simulations (MCs) and the scaled boundary finite element method (SBFEM) based on proper orthogonal decomposition (POD) and radial basis functions (RBF). The semianalytical solutions obtained by the SBFEM enable us to capture the stress intensity factors (SIFs) easily and accurately. The adoption

A concrete admixture with water retention and superhydrophobic properties was developed according to the high tensile strength, fissure resistance, and antiseepage requirements of concrete linings. Capillary water absorption, early-age anticracking, cube compressive strength, and splitting tensile tests were employed to study the effects of the new concrete admixture on the basic performance of concrete

Adsorbed gas and free gas both exist in shale reservoirs simultaneously due to the unique nanoscale pore structure, resulting in the complex flow mechanism of gas in the reservoir during the development process. The dynamic performance analysis of shale reservoirs has mostly been conducted by the numerical simulation and theoretical model, while the physical simulation method for relevant research