bluuebunny/crossref_metadata_2025_split huggingface dataset:
Interpretation method for laser-scanning point clouds of segmental tunnel linings based on hybrid analysis
Authors: Zhang Y , Liu X , Karlovšek J 
Published: May 2024

Abstract
Owing to its convenience and precision, laser scanning has been applied in inspecting segmental tunnel linings. The point clouds generated by laser scanning provide valuable geometric information regarding the lining profile. Numerous studies have identified defects including cracks, leaks, and concrete spalling from these point clouds. However, they primarily relied on computer vision and neglected the mechanical information inherent in point clouds. This paper proposes a method for interpreting laser-scanning point clouds related to segmental tunnel linings based on analytical back analysis, known as hybrid analysis. The objective involves interpreting the mechanical behavior of segmental tunnel linings derived from point clouds. Through hybrid analysis, the deformation of the segmental tunnel linings was broken down into deflection and rigid-body motion. This process revealed the contribution of joints to the overall deformation of the linings. The strain of the segmental tunnel linings can be further quantified using the elastic theory of an arch slender. To validate the hybrid analysis, results were compared with experimental monitoring results. Further, potential application scenarios for the proposed method were explored. This method holds promise in engineering practice because it requires limited knowledge of the external loads, rendering it suitable for in-operation tunnels buried in uncertain strata.
Study on the shear characteristics of the cemented soil-concrete interface after artificial freeze-thaw under vibration loading
Authors: Zhou J , Ban C , Liu C , Zhou H 
Published: May 2024

Abstract
Underground construction has reduced underground space. Consequently, engineering construction is being done near existing structures. The artificial ground freezing (AGF) method is effective in such projects, and cement is often used to reduce frost heave and thaw settlement. A cemented soil-concrete interface is formed around underground structures. The interface serves as the primary medium for interaction between the two materials. Therefore, the shear characteristics of the cemented soil–concrete interface after artificial freeze–thaw cycles under the influence of the surrounding vibration load in underground engineering must be understood. This study conducted large-scale interface shear tests of a cemented soil–concrete interface with vibration loading. The effects of curing time and artificial freeze–thaw cycles on interface shear characteristics were studied. Furthermore, unconfined compressive tests of the cemented soil under artificial freeze–thaw conditions were conducted. The shear strength of the interface increased with curing time. The shear strength of the interface and the unconfined compressive strength of the cemented soil increased rapidly in the early stage of curing and gradually slowed after seven days. Artificial freeze–thaw reduced the shear strength of the interface with vibration loading. The results enrich ongoing research on the shear characteristics of cemented soil-concrete interfaces.
Forward solution of shield tunneling pose based on the Newton–Raphson method
Authors: Han Yuzhen , Wang Xuyang , Nie Xiaofan , He Jizhong , Zhang Lianwei 
Published: May 2024

Abstract
To achieve precise control of the shield tunneling pose, obtaining a real-time shield pose state during the excavation process is necessary to achieve closed-loop feedback control of the shield pose. This study proposes a forward solution method to address the high cost and low efficiency of direct measurement methods, such as using lasers and gyroscopes, for measuring shield pose. This method relies on the real-time measurement of the strokes of hydraulic thrust cylinders during shield tunneling. Based on the inverse kinematics of the shield machine, the Newton–Raphson method was used to calculate the shield tunneling pose. Accordingly, a forward solution algorithm for shield pose was developed using MATLAB, and the effectiveness of the proposed method was verified through an example analysis. The results demonstrated the high computational efficiency of the method, proving its potential application in real-time control systems for shield tunneling poses.
Prediction of ground surface settlements by analytical and finite element methods
Authors: Wang Y H , Lam C C , Lok M H 
Published: May 2024

Abstract
The soil surrounding the excavation of shallow tunnels may experience destructive deformation near the tunnels. Particularly in densely populated areas where land resources are scarce, ground subsidence caused by tunnel excavation, which in turn affects surrounding structures, deserves more attention. Over the past few decades, various research methods for predicting the maximum vertical ground surface settlement have been proposed. In this study, an empirical estimation method, an analytical technique for evaluating ground movements, and a numerical simulation method using Plaxis 2D, a finite element model software, were selected as prediction approaches for ground surface settlements. Subsidence measurements were obtained from a metro tunnel excavated using an earth pressure balance shield tunnel boring machine and constructed in a dense sandy gravel layer. Comparison of the monitored deformations with the estimation results calculated by different prediction approaches showed that the maximum vertical settlement of the ground surface evaluated by the analytical technique and finite element model agreed well with the actual measured values. This suggests that these two prediction methods have the potential for conserving nearby structures during the construction of underground infrastructures.
Complex variable solution for ground deformation responses considering the grouting pressure of shallow shield
Authors: Huang Siyuan , Zhong Xiaochun 
Published: May 2024

Abstract
During shield tunneling in shallow strata, ground deformation is highly sensitive to grouting pressure response. Excessive grouting pressure can cause ground uplift, and an excessively low grouting pressure can cause excessive ground settlement, affecting the surrounding environment. Current studies seldom analyze the influence of shield excavation on ground deformation when the grouting pressure is considered. To ensure micro-disturbance of the surrounding environment during shield tunneling, this study presents a complex variable analysis method for analyzing the influence of grouting pressure on surface settlement. This solution maps the semi-infinite strata outside the segment into circular domains by introducing a complex function conformal mapping method. The nonuniform convergence deformation pattern BC-4 was introduced as the boundary condition for the displacement around the tunnel. The Laurent series expansion of the analytical function considering the grouting pressure in the circular domain was substituted into each boundary condition to solve the analytical function. Subsequently, the accuracy of the analytical method was verified by combining it with a finite element numerical method. Finally, the influence of grouting pressure on ground deformation under different working conditions was analyzed through parameterization. This analytical method can provide a theoretical basis for controlling grouting pressure parameters in shield tunnels.
Study on the escaping condition of backfill grouting based on two-phases flow for shield tunnelling during whole section rock
Authors: Zhu C , Ji B H , Li F D , Zhong X C , Jian Y Z , Gao W , Wu R H 
Published: May 2024

Abstract
During the process of full section surrounding rock shield tunneling, the occurrence of synchronous grout escaping can seriously affect the assembly quality of the detached shield tail segment ring. The segment is prone to quality accidents such as floating, misalignment of the tunnel pipes, and even cracking, and even a large number of rock fractures in the shield tail gap mix with water flow towards the excavation face and pressure chamber, leading to frequent fissure water gushing out of the screw conveyor. Taking the shield tunnelling section of Nanjing Metro Line 6 as the engineering background, this paper uses the finite element software Ansys Fluent to establish the two-phases flow shield tail escaping grout model, and analyzes the influence laws of the grout properties, grouting pressure difference, grouting escaping thickness and other factors in the process of grout escaping behind the shield tail wall based on Bingham fluid. The results show that the amount of synchronized grout escaping increases linearly with the increase of grouting pressure difference and grouting escaping thickness, and decreases with the increase of grout shear yield stress. The paper also discusses the three-dimensional curved surface of grout escaping volume, grouting pressure difference and grouting fluid properties behind shield tunnel tail in a full section surrounding rock shield project of Nanjing Line 6, and gives the measures to prevent grout escaping when the allowable grout escaping volume is not more than 1m3: when the grouting escaping thickness is 20mm, the grouting pressure difference should be controlled within 0.20∼0.25MPa, and the shear yield stress of the grouting fluid should be controlled within 300∼350Pa.
Optimization of blasting construction and vibration control technology of multi arch tunnels without central partition walls
Authors: Zhou Y , Xu J , Li P 
Published: May 2024

AbstractThe construction technology for multi arch tunnels without central partition walls is a new design method for multi arch tunnels. The construction technology of multi arch tunnels without central guide tunnels eliminates side and central guide tunnels, which not only accelerates construction progress but also ensures construction quality and safety. The excavation and support of the rear tunnel of a double-arch tunnel without a central partition are crucial to ensuring the overall stability of the tunnel structure. A combination of manual mechanical excavation and blasting excavation in some areas was used in the excavation and construction of the rear tunnel of the Chenjiachong Tunnel on the Chuyao Expressway in Yunnan in addition to damping materials and measures in the lining of the front tunnel, ensuring the safe excavation of the rear tunnel and the prevention of the lining of the front tunnel from cracking because of earthquakes, The on-site vibration monitoring results of the tunnel indicate that this technology has achieved good results. Overall, the optimized construction technology without a central partition greatly shortens the construction period and improves economic benefits. The construction method is simple and feasible and can be flexibly selected according to the surrounding rock conditions. This study can provide a reference for the construction of other highway tunnels in mountainous areas.
Analysis of tunnel collapse disasters during operation and exploration of disaster damage mechanisms
Authors: Lei B , Ding W , Huang X , Zhang Q 
Published: May 2024

Abstract
Highway tunnel collapse during the operation period is a serious threat to the stability of tunnel operation. Thus, it is important to investigate the disaster-causing mechanism to prevent the occurrence of disasters. In this paper, based on 155 cases of domestic and foreign highway tunnel collapses during operation, we statistically analyze the causes of the collapses and the year of occurrence, and we explore the disaster-causing mechanism of tunnel collapses through numerical simulation. Tunnel collapses in operation period are affected by geological factors, lining factors, and accidental factors. The primary causes of tunnel collapses are determined to be the post-lining cavity, lining crack expansion, and fire. A single factor cannot lead to tunnel collapse, and the probability of collapse increases under the coupling of multiple factors. Through a numerical simulation method, the evolution mechanism of tunnel collapse caused by the post-lining cavity is analyzed, which lays the foundation for establishing the tunnel collapse prediction model and qualitative risk assessment system of highway tunnel collapse.
Application of super large and deep diameter assembly shafts in soft soil layers
Authors: Long Y , Zhibing X , Xian L , Juntao N , Sebastian R 
Published: May 2024

Abstract
Considering the background of the Shanghai Jing’an Smart Garage Project, first, we introduced the world’s largest vertical shaft boring machine, which was suitable for vertical shaft excavation of diameter 12∼23 m. Then, we expounded the design points and key technologies of super large and deep diameter assembly shafts in soft soil layers. Finally, we verified the applicability of the vertical shaft boring technology in soft soil layers in Shanghai through on-site measurement results. It was observed that this technology had a minimal impact on the surrounding environment, indicating its potential for widespread applications in the coming years.
Calculation model of depth under quantification of surface morphology of dry shrinkage cracks in red clay
Authors: Ren Jiazhan , Yao Ying-jie , Dong Hui , Jing Ye 
Published: May 2024

Abstract
Cracks commonly form in clay owing to water loss, negatively affecting strength and hydraulic properties of soil, leading to rock and soil damage including landslides and dam instability. Understanding the changing patterns of the shrinkage crack depth is crucial for exploring slope infiltration patterns and determining key factors for slope stability. This study suggests a relationship between the surface and depth variations during cracking, and investigates the influence of the surface roughness on shrinkage cracks in saturated red clay. Regression analysis and machine learning algorithms were used to establish a depth prediction model. (1) Based on the surface morphology of shrinkage cracks, they are categorized into three types: linear, curved, and inflectional (linear and curved are the main types). (2) The surface roughness and development rate of surface cracks were positively correlated. (3) Based on the geometric parameters of the crack surface, a prediction model (error within 15%) for crack depth was established using multivariate nonlinear regression, providing a reference for the initial assessment of crack depth. These results provide a better understanding of the development patterns of shrinkage cracks, whose influence on slope stability is critical for mitigating the risks associated with slope instability and other soil failures.
Parameter sensitivity analysis of peak impact force for an actual flow-like landslide against a single rigid barrier
Authors: Zhang W J , Hong X Y , Zhang W , Wang X , Chen S X 
Published: May 2024

Abstract
Strength parameters are key factors that influence the sliding process of landslides and further affect the impact force on structures. Many scholars have previously studied the influence of strength parameters on slope stability; however, the influence of strength parameters on the impact force of flow-like landslides has not been analyzed till date. Therefore, in this study, the smoothed particle hydrodynamics (SPH) method was used to simulate the flow process of landslides and estimate the impact force on the rigid barrier by adjusting the strength parameters of landslides. The proposed SPH model was validated by a model test of dry sand impacting rigid barriers. The Gaoloucun landslide was selected as the study case and simulated to study the influence of parameters on the impact force. Finally, a multiple linear regression analysis was conducted to explore the sensitivity of impact force to input parameters and obtain the standardized regression coefficient, which was compared to find the dominant strength parameter. According to the results, among two strength parameters, the internal friction angle has more influence on the peak impact force than the cohesion.
A slope management method by monitoring soil volumetric water content and its validation through numerical analysis
Authors: Yoshida S , Xiong X , Muramatsu R , Fukada S , Matsumoto T 
Published: May 2024

Abstract
Landslides induced by heavy rainfall have become increasingly common in recent years. As the groundwater level rises, the safety factor of slopes tends to decrease. However, traditional monitoring methods, such as employing water-level (pressure) gauges in boreholes, require significant effort. Thus, this study proposes a slope management approach based on monitoring the volumetric water content of the ground surface. The monitored slope, approximately 20 m in height and 30 m in length, consists of topsoil mixed with grass roots and sand with a slight silt admixture, as revealed by two borehole investigations. Soil moisture meters were strategically installed at three locations along the slope (upper, middle, and lower sections) to gauge the volumetric water content. Observations indicated a sensitive increase in ground water content following rainfall. Furthermore, a three-dimensional Finite Element Method (FEM) analysis was employed to explore the correlation between rainfall (intensity and duration) and groundwater content. The FEM analysis also examined the impact of rainfall-induced changes in slope water content on the overall slope safety factor, utilizing 3D point cloud data to model the monitored slope. Qualitative agreement was observed between the monitoring and analysis results, highlighting a decrease in slope safety factor as slope water content increased. These findings underscore the potential of conveniently assessing slope safety factors based on the water content of a slope’s ground surface.
Landslide Susceptibility Mapping Using Machine Learning: A Case Study of Oregon
Authors: Wu Bin , Shi Zhenming , Peng Ming 
Published: May 2024

Abstract
Landslide susceptibility assessment, a crucial component of disaster prevention and mitigation, has traditionally relied on geological datasets and commonly used evaluation metrics. However, these metrics, often applied to 2D susceptibility maps, may not capture the full complexity of the issue. In this study, we incorporated spatial distribution data, including a historical landslide inventory, and integrated morphological, geological, hydrological, and land-use features. This approach enabled the construction of predictive models using eight distinct algorithms. The evaluation of classifier performance scores unveiled the superior performance of gradient tree boosting. In contrast, logistic regression struggled to handle the nonlinear aspects of landslide susceptibility analysis. A finding in our research was the consistent disparity in predictive susceptibility maps, even when similar performance scores were achieved across different algorithms. This underscores the necessity of combining evaluation metrics with spatial mapping in landslide susceptibility model assessment. We also highlighted the critical role of digital elevation models in constructing effective models when feature data was limited. Conversely, when abundant information was available, the integration of multi-source data significantly enhanced the precision of landslide susceptibility mapping. Overall, this study provides valuable insights for spatial prioritization in landslide field investigations and enhances our understanding of landslide risk assessment.
Influence of frequency characteristics of seismic ground motion on the fragility of an RC frame structure
Authors: Fei Yang , Chen Longwei , Lei Jinhui 
Published: May 2024

Abstract
Ground-motion frequency characteristics have a significant impact on structural damage. A quantitative description of the impact of ground-motion spectral features on structures is an urgent topic that requires solutions. In this study, the ratio of peak displacement to peak acceleration (R
d2a
) is used as a representative index of the ground-motion spectral characteristics. The seismic records collected from the Kik-net strong-motion array in Japan are grouped according to their R
d2a
values. By adopting the incremental dynamic analysis method, the seismic fragility curves of a six-story RC frame structure loaded by inputting seismic records with different R
d2a
values are calculated using the OpenSees platform. The influence of R
d2a
values on the structural fragility is analyzed. Ground-motion records of liquefied sites are collected, and the peak ratios of seismic records at the liquefied sites are analyzed to reveal the differences in the fragility of the six-story RC structures at liquefied and non-liquefied sites. The results of this study are expected to serve as a reference for the evaluation of structural fragility and to understand the effect of ground-motion frequency characteristics on the fragility of RC frame structures.
Influence of clay content on repeated liquefaction resistance of sand using element test
Authors: Zhong Y , Ni X , Zhang S 
Published: May 2024

Abstract
Soil liquefaction is a major concern because of its potential to cause building collapse, roadbed settlement, and sand eruptions. Field investigations have shown that clayey sand, when liquefied during mainshock, may undergo multiple liquefaction events during the subsequent aftershocks. Although previous research has primarily focused on the initial liquefaction event in clayey sand, research on the mechanism responsible for repeated liquefaction is limited. Consequently, a series of cyclic triaxial experiments are conducted on sand with varying clay contents, and these samples are subjected to various earthquake sequences. The primary objective of this study is to evaluate the cyclic behavior of sandy soil with clay content and analyze its repeated liquefaction resistance under different load sequences. A comprehensive assessment is conducted to understand the evolution of the repeated liquefaction resistance. The test results indicate that clayey sand exhibits the lowest liquefaction resistance during the second liquefaction event. Repeated liquefaction is dominated by stress-induced anisotropy at earlier events and relative density at the final events.
Evaluation of large axial strain of granular sand in post-liquefaction stage using DEM simulation
Authors: Ma Junnan , Ni Xueqian , Zhang Feng 
Published: May 2024

Abstract
Field investigations in recent studies have revealed that significant damage to foundations often occurs in the post-liquefaction stage, during which sand undergoes substantial deformation. As a result, numerous researchers have dedicated considerable effort to studying the evolution of the axial strain at this stage. However, the accurate measurement of the exact value of this strain is challenging mainly owing to the limitations of the triaxial apparatus. In this study, the numerical method of discrete element method (DEM) is used to simulate undrained cyclic triaxial loading tests according to a large number of loading cycles. The mechanical behaviour of granular sand under different cell pressures was reproduced using the DEM method, wherein the liquefaction resistance increased with the cell pressure. The post-liquefaction axial strain exhibited a similar pattern of variation among the calculated cases at different cell pressures. The value of the double amplitude of the axial strain stabilised at a maximum value after a certain loading cycle. The microscopic characteristics derived from the DEM calculations, including the contact number and force chain network, were analysed to provide reasonable explanations. The sand fabric was re-established after a large number of loading cycles and controlled by cyclic loading, which helped stabilise the accumulated axial strain.