Stress-strain and fracture acoustic emission dataset of high-strength concrete for metro tunnel lining under different stress states.

The maintenance of metro tunnel support structures is crucial for ensuring the safe and efficient operation of urban rail transit. Under complex stress conditions (including tension, compression, shear, torsion), metro tunnel linings are susceptible to various forms of damage, such as cracking, spalling, segment misalignment, and water leakage. These issues pose substantial challenges to tunnel safety and service life.

Carbonation and Corrosion Durability Assessment of Reinforced Concrete Beam in Heavy-Haul Railways by Multi-Physics Coupling-Based Analytical Method.

The operation of heavy-haul railway trains with large loads results in significant cracking issues in reinforced concrete beams. Atmospheric carbon dioxide, oxygen, and moisture from the atmosphere penetrate into the beam interior through these cracks, accelerating the carbonation of the concrete and the corrosion of the steel bars. The rust-induced expansion of steel bars further exacerbates the cracking of the beam.

Numerical analysis of the effect of vegetation root reinforcement on the rainfall-induced instability of loess slopes.

Rainfall-induced instability of loess slopes presents significant threats to infrastructure and ecological systems. Vegetation serves as an effective measure to enhance slope stability through mechanical reinforcement by roots and hydrological regulation of soil moisture. The influence of vegetation root system characteristics, including root tensile strength and rooting depth, on the stability of loess slopes subjected to rainfall infiltration is investigated using a finite element model developed in COMSOL®, which couples seepage and mechanical behavior.

Study on the disaster mechanism and prevention technology of embankment slip-collapse after extreme rainfall in the loess area.

This study investigates railway embankment slip-collapse disasters triggered by July 2021 extreme rainfall in Zhengzhou, China, through field investigations, in-situ tests, laboratory tests, field monitoring, and numerical simulations. The research results indicate that: (1) Zhengzhou loess experiences accelerated strength degradation when moisture content exceeds plastic limit, with shear modulus, cohesion, and internal friction angle decreasing rapidly beyond this threshold. (2) Embankment slip-collapse, a geohazard characterized by shallow failures in slope surfaces, is primarily triggered by hydro-mechanical coupling under extreme rainfall, with deformation severity controlled by infiltration intensity.

Triple-chord trussed submerged floating tunnels: hybrid construction concept, feasibility and design.

Submerged floating tunnels (SFT) offer a promising solution for deep-water crossings and intercontinental transportation. However, current SFT designs struggle to meet the high structural performance demands associated with the harsh service environments while remaining economically viable, thus limiting their implementation in practice. Here, we propose a conceptual SFT design using a triple-chord trussed concrete-filled double-skin tubular (CFDST) hybrid structure, featuring CFDST chords and hollow steel tubular braces.

Orientation of Nonspherical Nanoparticles in Ordered Block Copolymer for Functional Materials.

In the fields of controllable catalysis, electromagnetic field manipulation, and nanoscience, mediated self-assembly has become a key method for controlling the orientation of nonspherical nanoparticles. The ordered structures formed by block copolymer self-assembly can provide an orientation matrix for nonspherical nanoparticles. Based on self-consistent field theory, this study investigates the orientation effects of monaxially symmetric cylindrical nanoparticles in the lamellar phases formed by block copolymers.

CFD-DEM simulation of the motion law of magnetic flocs during waste slurry disposal in shield tunnel.

The sustainable treatment and reuse of waste slurry in slurry shield construction have gained significant attention. This paper explores the application of magnetic flocculation technology for treating slurry. The CFD-DEM coupling method simulates the migration of magnetic flocs during centrifugation.

Performance Evaluation of Stabilized Soils with Selected Common Waste Materials of Rice Husk Ash, Steel Slag and Iron Tailing Powder.

Soil stabilization technology has been applied for a long time in the infrastructure construction field. Currently, the use of waste materials as stabilizer is growing in attention, because it promises to develop green and high-performance soil stabilization efficiency. In this work, three common waste materials, including rice husk ash (RHA), steel slag (SS) and iron tailing (IT) powder, were selected and synergistically utilized with cement to prepare stabilized soil.

A case study on risk assessment and novel anchoring technology for potential collapse of high and steep giant dangerous rock mass.

Dangerous rock masses in mountainous areas seriously threaten the construction and operation of engineering with potential disaster hazards, especially the unpredictability and sudden occurrence of rockfall, which poses a huge challenge. This paper presents a systematic risk assessment and disposal of high and steep giant dangerous rock masses, which can pose a serious threat to railway operation. Using comprehensive methods such as on-site investigation, limit equilibrium method, and simulation analysis of rockfall trajectory, the possibility and potential harm of collapse and rockfall of giant dangerous rock masses are analyzed and corresponding remediation measures are proposed.

Evolutionary analysis of slope direction deformation in the Gaojiawan landslide based on time-series InSAR and Kalman filtering.

The existing landslide monitoring methods are unable to accurately reflect the true deformation of the landslide body, and the use of a single SAR satellite, affected by its revisit cycle, still suffers from the limitation of insufficient temporal resolution for landslide monitoring. Therefore, this paper proposes a method for the dynamic reconstruction and evolutionary characteristic analysis of the Gaojiawan landslide's along-slope deformation based on ascending and descending orbit time-series InSAR observations using Kalman filtering. Initially, the method employs a gridded selection approach during the InSAR time-series processing, filtering coherent points based on the standard deviation of residual phases, thereby ensuring the density and quality of the extracted coherent points.

Experimental study on the bearing capacity and effective anchorage lengths of inclined steel grouting pipes in loess embankment slope.

Splitting grouting is widely used to reinforce unfavorable soil stratum. Inclined steel grouting pipe is a type of structure which can achieve splitting grouting in soil stratum. It has been successfully utilized in argillaceous sandstone stratum, but its application in loess stratum has rarely been studied directly.

Cationic Amphiphilic Comb-Shaped Polymer Emulsifier for Fabricating Avermectin Nanoemulsion with Exceptional Leaf Behaviors and Multidimensional Controlled Release.

The development of intelligent multifunctional nanopesticides featuring enhanced foliage affinity and hierarchical target release is increasingly pivotal in modern agriculture. In this study, a novel cationic amphiphilic comb-shaped polymer, termed PEI-TA, was prepared via a one-step Michael addition between low-molecular-weight biodegradable polyethylenimine (PEI) and tetradecyl acrylate (TA), followed by neutralization with acetic acid. Using the emulsifier PEI-TA, a positively charged avermectin (AVM) nanoemulsion was prepared via a phase inversion emulsification process.

Robust structural superlubricity under gigapascal pressures.

Structural superlubricity (SSL) is a state of contact with no wear and ultralow friction. SSL has been characterized at contact with van der Waals (vdW) layered materials, while its stability under extreme loading conditions has not been assessed. By designing both self-mated and non-self-mated vdW contacts with materials chosen for their high strengths, we report outstanding robustness of SSL under very high pressures in experiments.

Predicting soil thermal properties in freeze-thaw cycles using EFAttNet: A comparative analysis.

This study investigates the thermal conductivity (λ) and volumetric heat capacity (C) of sandy soil samples under a variety of conditions, including freeze-thaw cycles at temperatures both above and below zero and differing moisture levels. To estimate these thermal properties, a novel predictive model, EFAttNet, was developed, which utilizes custom-designed embedding and attention-based fusion networks. When compared to traditional de Vries empirical models and other baseline algorithms, EFAttNet demonstrated superior accuracy.

Shaking table test on damage mechanism of bedrock and overburden layer slope based on the time-frequency analysis method.

To systematically analyze the damage caused by bedrock and overburden layer slope under seismic action, a set of large-scale shaking table test was designed and completed. Interpolation of the acceleration amplification coefficient, Hilbert-Huang transform and transfer function was adopted. The damage mechanisms of the bedrock and overburden layer slopes under seismic action are systematically summarized in terms of slope displacement, acceleration field, vibration amplitude, energy, vibration frequency, and damage level.

Study on monitoring broken rails of heavy haul railway based on ultrasonic guided wave.

Real-time monitoring of broken rails in heavy haul railways is crucial for ensuring the safe operation of railway lines. U78CrV steel is a common material used for heavy haul line rails in China. In this study, the semi-analytical finite element (SAFE) method is employed to calculate the dispersion curves and modal shapes of ultrasonic guided waves in U78CrV heavy steel rails.

Experimental Research on Fatigue Behavior of Reinforced UHPC-NC Composite Beams under Cyclic Loading.

Ultra-high-performance concrete (UHPC), a new cement-based material that offers high mechanical strength and good durability, has been widely applied in construction and rehabilitation projects in recent years. An optimum bending system is achieved by positioning the UHPC layer at the bottom tensile zone of the composite beam and placing the normal-strength concrete (NC) layer at the upper compression zone, which is described as the UHPC-NC composite beam. The fatigue behavior of reinforced UHPC-NC composite beams was described in this study, with an emphasis on the effects of UHPC layer thickness and fatigue load level on the fatigue life of the beam, deformation of the interface between UHPC and NC layers, as well as the bending stiffness of the beam.

Effect of Sulfate Attack on the Expansion Behavior of Cement-Treated Aggregates.

The expansion induced by sulfate attack on cement-treated aggregates (SACA) is a well-known problem that can be solved. It causes obvious heaves in road bases and railway subgrades. In this paper, the effects of the sodium sulfate content, cement content, degree of compaction, sulfate types, attack types, aluminum ion supply, concentration of curing sulfate solution, and temperature on the expansion behavior induced by SACA were investigated over 60 days in the laboratory.

Quasi-3D slope stability analysis of waste dump based on double wedge failure.

The double wedges sliding along the weak layer of the foundation can be observed on the slope of the waste dump and the sliding body is divided into the active wedge and passive wedge by the weak foundation and the failure surfaces of the waste dump. Because the conventional limit equilibrium slice method cannot reflect the polygonal slip surface of the slope of the waste dump with weak foundation, this study proposed a double wedge calculation method for the slope of the waste dump with weak foundation. The limit equilibrium analysis is performed on double wedges by considering the direction and values of the interaction force between double wedges to obtain the safety factor of the slope of the waste dump.

Application of environmental protection investment benefit model of coal enterprises in environmental protection construction of smart city.

The purpose is to strengthen the construction and application of smart environmental protection cities and establish the benefits model of enterprise environmental protection investment (EPI). This paper introduces its related concepts based on EPI and financial performance theory. It analyzes the current situation and existing problems of EPI, environmental information disclosure level (EADI), and financial performance of the coal industry and enterprises.

Combined CNN and RNN Neural Networks for GPR Detection of Railway Subgrade Diseases.

Vehicle-mounted ground-penetrating radar (GPR) has been used to non-destructively inspect and evaluate railway subgrade conditions. However, existing GPR data processing and interpretation methods mostly rely on time-consuming manual interpretation, and limited studies have applied machine learning methods. GPR data are complex, high-dimensional, and redundant, in particular with non-negligible noises, for which traditional machine learning methods are not effective when applied to GPR data processing and interpretation.

A long term resilient modulus rate dependent model for coarse fine mixtures geomaterials under freezing and thawing cyclic.

The cyclic loading frequency (f) effects on the resilient modulus (M) of freezing-thawing coarse-fine mixtures geomaterials (FTCFG) have always been a research hotspot. A series of long-term cyclic triaxial tests were conducted on FTCFG having different fines content (FC) under different number of freeze-thaw cycles (N) to investigate the effect of f and deviator stress amplitude (q) on the M of FTCFG. The freezing-thawing cyclic was found to improve the M of FTCFG.

A Nonlinear Constitutive Model for Remoulded Fine-Grained Materials Used under the Qinghai-Tibet Railway Line.

Using undrained triaxial shear tests, this study investigates the mechanical properties of fine-grained materials (silty clay and sand) which are extensively used for China's Qinghai-Tibet Railway (QTR) under different confining pressures () and freezing temperatures (). The results show that a reduction in causes an increase in the shear strength and elastic modulus of all the materials tested in the present study. In addition, the freezing of the silty clay has no significant effect on the type of soil behaviour (strain-hardening), whereas the freezing of the sand changes its strain-hardening behaviour to strain-softening.

Classification of the loosening zones and estimation of the loosening pressures of tunnels in layered jointed rock strata.

Due to the complexity of tunnels, accurate prediction of their loosening pressures in layered jointed rock strata is a very difficult engineering task. To recognize loosening patterns and estimate loosening pressures, numerical tests were employed in areas where tunnels were excavated in layered jointed rock strata. A total of 12 influential factors, including joints, tunnel depth, and strata, were considered in each of the numerical models.