bluuebunny/crossref_metadata_2025_split huggingface dataset:
Design of composite foundation for high-rise buildings in complex red bed karst site
Authors: Wei ping PENG , Zhong yi WEN , Xi PENG , Wei LIU , Qinghua ZHANG 
Published: November 2020

Abstract
Ground collapse occurs frequently in deep foundation construction in the shallow overlying rock-karst area, constituting a major hidden danger to personal safety and engineering quality. This study reveals the structural characteristics of honeycomb heterogeneous anisotropic rock mass through the geological radar scanning and the foundation optimization design of a high-rise building (35 floors) in the red layer karst site. Meanwhile, the giant karst cave pipeline is filled and reinforced by karst grouting, and an artificial dam is constructed to block the groundwater transport channel. Based on the analysis results of the stability against the punching and cutting of the karst cave roof, the composite foundation of the plain concrete rigid pile with low-bearing capacity and high replacement rate is proposed. Regarding the extremely thin karst cave roof area, the steel pipe pile is used for underpinning and reinforcement, effectively avoiding the risk of local instability and construction collapse caused by the effective length of the pile and large stress at the pile end. After completing the building, it runs well. Meanwhile, the monitoring shows that the maximum settlement deformation of the high-rise building is only 9.63 mm.
Study on hysteretic deformation characteristics and energy dissipation of granite under cyclic loading
Authors: Han Chao , Li Dejian , Rao Yuanhao , Wang Jiwei 
Published: November 2020

Abstract
The cyclic load test of granite under different paths is conducted using the strain control method. The nonlinear hysteretic deformation behavior is analyzed, and the energy evolution law in the process is described in detail. Three specific discoveries were made. (1) The skeleton curve shape in the cyclic test is less affected by the increase in the upper load limit and shows good loading memory characteristics. (2) The hysteretic characteristics of the stress-strain curve characterize the energy dissipation process. Dissipated energy is divided into plastic hysteresis and damping energy consumption. Damping energy consumption accounts for a considerable proportion of the total energy consumption at all levels, and the changing trend of the two is positively correlated. The upper limit of the cyclic load can significantly change the plastic hysteretic energy. (3) The loading-unloading process is more prone to large hysteresis deformation, and the unloading-reloading process has an unloading threshold. When the unloading amount is less than the threshold, the unloading-reloading curve linearly coincides, and the energy is dissipated during the process. When the unloading amount is greater than the threshold, damping energy will be generated to increase energy dissipation, and the hysteresis characteristic will appear.
Study on the mechanism of dynamic slip-weakening for a rock material interface based on a vibration experiment
Authors: Zhang K , Liu Y R , Yang Q 
Published: November 2020

Abstract
Slip-friction of faults and joint fractures is of great significance in the study of rock mass structural engineering stability and earthquake generation mechanism. Laboratory friction experiment is a great method to determine the frictional strength of rock interfaces. A large number of low-velocity experiments has been conducted to explain the friction mechanism in the regime of direct shear mode. However, the friction mechanism in the regime of vibration mode has rarely been studied. To study the slip-friction mechanism of rock interface under the vibration mode, a dynamic friction experiment with two blocks on a vibrating platform was performed. The experiments were conducted with hard granite samples at a vibration frequency of 1–10Hz, vibration amplitude 0.5–5mm, and normal stress of 0.5–4.5MPa. The results demonstrate that slip- and frequency-weakening phenomena were noticed and the general quantitative relationship of the three characteristic friction parameters is μ
3 > μ
1 > μ
2. Moreover, the normal stress has a significant effect on the weakening degree of the friction coefficient, and the change in the surface roughness may correlate with the change in the weakening degree.
A proposed method for mathematical quantitative description of fractures from borehole wall images
Authors: Han Zengqiang , Wang Chuanying , Jiao Yuyong , Wang Chao , Wang Jinchao 
Published: November 2020

Abstract
Fractures from borehole wall images are different from those from surface outcrop in trace pattern, distribution pattern, parameters description and so on. Focus on the geometric parameters of fractures from borehole images, a method for mathematical quantitative description of these fractures is proposed. The fracture from borehole images is described into a point in spatial coordinate system, and this point is defined Fracture Feature Point. The key parameters including dip direction, dip angle and position depth of fractures from borehole wall images are converted into coordinates of fractures feature points. The related calculation equations are deduced in local coordinate system and spatial coordinate system. Furtherly, the space distribution regularities of the fractures based on the distribution characteristics of fracture feature points are summarized. Typical application in multiple boreholes of this description method is studied and an analysis method for any two fractures’ connectivity is established based on Fracture Feature Point. The results of an engineering example research show that the method is effective in fractures connectivity analysis. The mathematical quantitative description method of fractures from borehole wall images will provide new ideas of the research on deep rock mass structure.
Strain Response of Tunnel Anchor Using Rayleigh Scattering-based Optical Fiber Sensing Technology in the Field Test
Authors: Shuai Wang , Yihu Zhang , Wei Hu 
Published: November 2020

Abstract
Tunnel anchor is a relatively new type of anchor for suspension bridges. Loading tests on a scale model in site are generally considered to be the most direct way to evaluate the bearing capacity of the tunnel anchor system. The response of the anchor body has received minimal attention and involves only a few or no measuring points, because the anchor plug does not undergo elastoplastic failure in a model test. This article intends to explore the relationship between the strain response of the anchor and the state of the surrounding rock. Optical fiber strain sensing technology based on adjustable wavelength optical time domain reflectometry (i.e., TW–COTDR) was applied to the scale model test of Baotaping Bridge tunnel anchor. The strain distribution and evolution of the entire anchor body were determined by optical measurements during overload. In the elastic and plastic stages of the anchor system, the strain around the anchor body linearly decreased from back to front, except for the top arch and the bottom plate at the end. The anchor strain–load curve was nonlinear, similar to the displacement–load curve, but unrelated to concrete damage, which signaled that plasticity began to appear in the anchor system. Therefore, the strain response of the anchor body can be used as an alternative to determine bearing capacity of the anchor system, especially when the displacement is too small to observe.
Deformation response and anchorage control of excavation unloading of high and steep rock slope
Authors: Dong Zhihong , Ding Xiuli , Huang Shuling , Wu Yongjin , Wu Aiqing 
Published: November 2020

Abstract
The stability and anchorage control of high and steep slopes in Southwest China are challenging problems in engineering construction. Considering the unloading stability of high and steep rock slopes, field monitoring and numerical analysis methods are used for feedback analysis to study the deformation, stress response, anchorage support scheme, and anchorage stress characteristics during the unloading process of slope excavation. The research shows that the displacement of rock mass of the high slope gradually increases and the local deformation exceeds 200 mm. The unloading relaxation area resulting from slope excavation is 25 m deep. The safety of the slope can be guaranteed after the joint reinforcement of deep anchor cable.
In-situ stress measurement technology and field application based on micro-optical imaging measurement method
Authors: Wang Yiteng , Wang Chuanying , Han Zengqiang , Wang Chao , Hao Haiyang 
Published: November 2020

Abstract
In-situ stress is natural stress existing in rock masses. As an important basic parameter, accurate in-situ stress is highly beneficial to the theoretical research and engineering application of rock mechanics. In-situ tests in boreholes are the most direct and effective way to obtain in-situ stress. However, the high temperature and high water pressure testing environment in boreholes limits the application scope of measurement sensors. In this study, a micro-optical imaging measurement method is proposed. On the basis of this method, an aperture measurement device is developed, and a complete set of in-situ stress measurement technology is formed. Laboratory and field application tests are carried out. The results of the temperature and pressure test in a laboratory show that the in-situ stress test technology improves service temperature and pressure and offers an extensive application range. The field test on a shallow borehole in an iron mine roadway and a deep borehole in a shale gas exploration well reveals the deformation of the test boreholes in the process of stress relief. This result proves the feasibility of the in-situ stress measurement technology. On the basis of the theory of elasticity, in-situ stress is calculated with reference to the in-situ diameter deformation of the boreholes and the mechanical parameters of the rock core. A number of in-situ stress tests are carried out under different borehole depths, and the testing times are recorded. Results show that the application of wireline coring drilling technology speeds up the test process. Hence, it can boost the operability of the in-situ stress test. In sum, the in-situ stress measurement technology based on the micro-optical imaging measurement method is feasible and operable and may thus improve the application depth of the in-situ stress measurement method based on the stress relief method.
Disaster characteristics and cause analysis of railroad slope in complicated and dangerous mountainous areas
Authors: Liu Hongyu , Ma Xianjie , Li Jian , Li Jiaming , Li Wei , Hou Lijie 
Published: November 2020

Abstract
With the vigorous development of China’s railroad industry, increased railroad construction has extended to complex and dangerous mountainous areas. During the construction and operation of railroads in this area, various geological disasters are inevitable, bringing significant difficulties to railroad construction and significant threats to personal safety. This study focuses on the typical railroad passing through dense and dangerous mountainous areas as the research object. Through on-site investigations, the characteristics of slope disasters along the railroad were analyzed following the laws of disaster distribution and characteristics of disaster development. The study analyzes the causes of slope disasters by investigating internal and external factors. The research results show that the geological disasters along the railroad can be divided into landslides and collapses, of which there are 8 landslide disasters and 15 collapse catastrophes. Landslides are characterized as creeping and fretting stages according to their development characteristics. Collapses can be divided into four types of dangerous rock masses according to the scale of disaster distribution. Many factors influence the development of landslide geological disasters, and the development of geological disasters is the result of the combined action of multiple influencing factors. By analyzing the slope disaster along the railroad, this study provides an effective reference basis for constructing complex mountain railroads in the future.
DFOS-based association rules analysis on the multi-fields information of Majiagou landslide
Authors: Zhang Lei , Shi Bin , Zheng Xing , Sun Yi-Jie 
Published: November 2020

Abstract
The multi-fields information of landslide can be obtained using distributed optical fiber sensing (DFOS) technology. Nevertheless, it is still a quite complicated work to analyze massive amounts of multi-fields information, and to evaluate the slope stability under multifields coupling effect. This paper introduced a data mining method named association rules analysis, and designed a DFOS-based monitoring system to record the multi-field information, including strain field, deformation field, seepage field, temperature field and environmental parameters, respectively. Taking Majiagou landslide as an example, the association rules analysis of the multi-field monitoring information revealed the reservoir water level is the domain factor that influences the deformation of Majiagou landslide. The correlation analysis method can explore the internal relationship among different fields of a landslide and provide scientific basis for slope stability evaluation and landslide early-warning.
Borehole parameter optimization for supercritical carbon dioxide phase-transition fracturing
Authors: Cheng W J 
Published: November 2020

Abstract
In recent years, supercritical carbon dioxide phase-transition fracturing (SCDPTF) has extensively been used in rock engineering as an environmentally friendly rock breaking technology. It is important to improve the energy efficiency and rock breaking effect by examining the SCDPTF borehole parameters. In this study, SCDPTF was first analyzed by numerical simulations. Based on the numerical simulation results, field tests were subsequently performed to determine the optimal borehole parameters. The results indicate that the rock mass around the borehole under the carbon dioxide phase-transition fracturing load can be divided into a crushing zone, a cracking zone, and a vibration zone. The radius of the crushing zone was ~0.297 m and that of the cracking zone was ~1.399 m, respectively. The optimal minimum burden line was 1.8 m, and the optimal borehole spacing was 2.5 m, respectively. The abovementioned results could provide effective guidance for the parameter design of SCDPTF.
Study on dynamic response of rock foundation pit blasting excavation to adjacent buildings
Authors: Jiang Teng-fei , Jiang An-nan , Li Xing-sheng 
Published: November 2020

Abstract
Focusing on safety problems of the blasting excavation of foundation pits near existing buildings, this study takes the Jinggangshan Road Station of Qingdao Metro Line 1 as the engineering background and establishes a three-dimensional numerical model of a foundation pit blasting excavation based on the dynamic response characteristics of buildings using the FLAC3D finite difference software. Moreover, the present study examines the dynamic response law of foundation pit blasting excavations under blasting vibrations and analyzes blasting vibration velocities at different measuring points near buildings. Results show that the blasting vibration velocity of key measuring points is consistent with the numerical simulation results. This finding demonstrates that the numerical model is reasonable; the influence of blasting vibrations on buildings presents different trends with varying heights, mainly concentrated in the lower part of the blasting side; the vibration velocity of the measuring points of buildings varies with different horizontal distances; and the impact of the monitoring points near the blasting side is far greater than that of the measuring points far from the blasting side. Velocity decreases as the distance between the detonation centers increases. The results have certain reference value and guiding significance in the selection of reasonable blasting parameters and the effective improvement of the safety threshold of foundation pit blasting vibrations.
Experimental Research on In-situ Monitoring of Coalbed Methane Extraction Pipes in a Coal Mine Working Face
Authors: Sang Haomin , Wang Zhiqiang 
Published: November 2020

Abstract
To study the stress and deformation characteristics of the coalbed methane (CBM) extraction pipe and to overcome the obstruction of the CBM extraction channel, an in-situ monitoring test of the extraction pipe was performed based on a coal mine working face in the Huainan mining area. According to the data of CBM overrun and field situation, the in-situ stress and deformation test of the CBM extraction pipes was designed and implemented, and the actual stress variation and deformation of the extraction pipe in the borehole was measured, which revealed the mechanical properties of the CBM extraction pipe as the working face advanced. The results show that the stress value of each measuring point increased as the working face advanced, and there was obvious stress concentration at the depth of 50 m. When the working face was ~35 m away from the test hole, there was a major increase in the stress growth rate. This work has guiding significance for the reasonable selection of CBM extraction pipes and optimization of extraction schemes in deep coal mines.
Factors affecting the deformation of the surrounding rock of tunnel based on rough set theory
Authors: Hou Shoujiang 
Published: November 2020

Abstract
The deformation of surrounding rock is a common hazard in tunnel engineering, and it can negatively affect the quality and safety of a project. Therefore, the analysis of factors affecting the deformation of tunnels surrounding rock has essential engineering significance. This work selected two subjective factors affecting the deformation of the surrounding rock of a tunnel, namely, the excavation method and the excavation footage, and four objective factors (i.e., the tunnel burial depth, the degree of weathering, the groundwater conditions, and the uniaxial compressive strength of rocks) as the factors affecting the deformation of tunnel surrounding rock. Data on the factors influencing deformation of 25 typical deformation sections of the Tianqiao Mountain Tunnel under construction were collected to establish the condition attributes in the decision table. The actual deformation level was used as the decision attribute in the decision table. Rough set theory was used to perform a completely objective analysis of these six factors. Results of the analysis show that the groundwater conditions are the most influential factor in surrounding rock deformation with a weight of 0.3333, and the degree of weathering is a redundant factor. This study can be used as a guide for reducing or avoiding the deformation of the surrounding rock of a tunnel.
Case study: Analysis of the correlation between casing deformation and fracture zone in Changning Block, Sichuan
Authors: Zhaowei Chen , Hu Cao , Xiaojin Zhou , Qiyong Gou , Haozhe Zhang 
Published: November 2020

Abstract
Casing deformation is an engineering problem that restricts the efficient development of shale gas in the Sichuan Basin. This paper analyzed the correlation between 67 casing deformation points and 256 fracture zones in the N201 wellfield, and conducted a statistical analysis of the distribution of the orientation of fracture zones, which may have/have not caused casing deformation. The Mohr–Coulomb criterion was used to analyze the stress state and the slip risk of these fracture zones. The results show indicate the following. (1) Fracture zone is the main factor leading to casing deformation. (2) Fracture zones with 60°–90° and 110°–120° orientations are likely to cause casing deformation, whereas fracture zones with 50°–70° orientation are relatively less likely to cause casing deformation. (3) The analysis of stress state shows that the orientations of high-risk fractures range from 74°–100° and 130°–160°, the orientations of medium-risk fractures range from 64°–74°, 100°–130°, and 160°–170 °, and the orientations of low-risk fractures are in the range of 0°–64° and 170°–180°. The theoretical results are basically consistent with the field statistical results. These results provide an explanation for the field statistical results in theory. This work not only demonstrates that a fracture zone is the major geological factor that causes casing deformation, but also provides a feasible method for us to predict the casing deformation in the future.
Landslide Susceptibility Prediction Based on the Information Value-Logistic Regression Model and Geographic Information System
Authors: Huang Faming , Ye Zhou , Zhou Chuangbing , Yao Chi , Hu Qichao , Jiang Shui-Hua 
Published: November 2020

Abstract
The landslide susceptibility prediction (LSP) is generally implemented using certain types of single models; however, certain drawbacks exist in the single models; e.g., it is difficult to clearly reflect the weights of landslide-related environmental factors if only the information value (IV) model is adopted. To overcome these limitations, this study proposes an IV-logistic regression (IV-LR) model for LSP. The landslides that occurred in the southern part of Chongyi County, China, are used as study cases. Nine environmental factors—elevation, slope, plane curvature, profile curvature, relief amplitude, distance to river, lithology, normalized difference vegetable index, and normalized difference built-up index—are adopted based on remote sensing and geographic information system. Certain landslide grid units and the same number of non-landslide grid units are used as the output variables of these models. The IV, LR, and IV-LR models are used to implement the LSP in the southern part of Chongyi County. The predicted landslides susceptibility in Chongyi County mostly occurred in areas with low elevations, close distance to rivers, carbonate lithology, low vegetation coverage rate, and densely populated areas. The results show that the prediction rate of the IV-LR model (80.4%) is higher than that of the LR model (76.8%), followed by the IV model (72.8%); they further demonstrate that the IV-LR model has its unique superiority and rationality compared with the IV and LR models.
Regional-scale detection of unrecorded landslides in mountainous terrains by using interferometric stacking technique
Authors: Chen Lichuan , Liu Pengfei , Liao Weiming , Zhang Kui , He Fei , Zeng Liang 
Published: November 2020

Abstract
Landslide hazard investigation by using a standard geological survey in a mountainous terrain can result in low accuracy and poor update rate. These deficiencies could lead to unrecorded landslides, which could be catastrophic. Synthetic aperture radar interferometry (InSAR), which can detect subtle ground surface movements in large areas, is considered as a promising solution for detecting unrecorded landslides in mountainous terrains. To evaluate its feasibility, this study conducted analysis work and associated field survey in Fengjie County. The county is characterized by a mountainous terrain and is located in a notoriously landslide-prone area in the Three Gorges reservoir in China. A total of 30 SAR images captured by the Sentinel-1A satellite in 2018 were processed to obtain the ground surface movements of the county. InSAR results identified 276 anomalous regions that were not recorded in the local inventory map. Of these regions, 18 were verified as unrecorded landslides on the basis of the field survey. The observable deformation of the landslides recorded in the local inventory map was also detected by InSAR. This work, which is not supposed to diminish the importance of standard geological surveys, could improve the accuracy and update rate of local inventory maps.