Widely used hydration promoters primarily improve the early strength of steel slag supplementary cementitious materials (SCMs) but offer limited enhancement to later strength and fail to mitigate early hydration inhibition by steel slag (SS). This study introduces a novel organic hydration promoter, Triethanolamine-Gallate (TG), synthesized by modifying gallic acid with triethanolamine. TG imparted

This paper employs the discrete element method (DEM) to simulate the nanoindentation creep of calcium-silicate-hydrate (C-S-H), focusing on indentation deformation, particle interactions, and stress transmission paths. The Rate Process Theory (RPT), previously utilized in the creep modeling of cohesive soils and other granular materials, is proposed to simulate C-S-H creep. Due to the nanometer size

MgO-SiO2 cement was produced by combined calcination of MgCO3 and kaolin as raw materials, at a MgCO3/kaolin mass ratio of 75/25 and 800 ºC for 45 min. Separate calcination of MgCO3 and kaolin was also conducted under the same conditions. Raw materials were characterized based on their chemical composition, bulk density, particle size distribution, XRD, FTIR, and BET specific surface area, and the

The rapid advancement of renewable energy highlights the urgent need for safe, cost-effective, and scalable energy storage solutions, particularly for net-zero energy buildings. In this study, we introduce an innovative energy storage solution utilizing fly ash-cement composites (FCS) as multifunctional components. The FCS, incorporating fly ash as a mineral admixture, achieves a refined pore structure

This study investigated the passivation ability and chloride-induced corrosion behavior of galvanized steel in the pore solutions of belitic calcium sulfoaluminate (BCSA) cement. Pure zinc was used to simulate the galvanized coating, and ordinary Portland cement (OPC) solution was also tested for the comparison purpose. A comparable passivation behavior was observed for pure zinc in the OPC solution

This paper investigates the influence of the water absorption-release process of superabsorbent polymer (SAP) with varying amounts of extra-entrained water on the properties of the surrounding cement paste and the macroscopic cement paste. 1H low-field nuclear magnetic resonance (NMR) was used to analyze the water absorption-release process of SAP. The macroscopic properties, including the void system

Ultra-high-performance concrete (UHPC) is a promising material for constructing future deep underground spaces owing to its exceptional toughness and durability. Nevertheless, the potential impact of stray currents and high hydraulic pressure on the durability of UHPC in deep underground electric projects (such as subways and electric railways) remains elusive. Moreover, existing experimental setups

This paper investigates the bond performance of a hybrid lap-spliced connection of glass fiber reinforced polymer (GFRP) bars and stainless steel bars in concrete. To gain a comprehensive understanding, micro-level and macro-level mechanical studies are conducted. First, the microstructural characterization of GFRP bars is performed to comprehend the specific material features. Then, cantilever tests

Behavior of different PCEs (MPEG (methacrylate ester), HPEG (methallyl ether), EPEG (2-hydroxyethyl poly(ethylene glycol) vinyl ether) based PCE) in NaOH-/Na2SiO3-activated two-part slag binders was investigated. In both activator solutions their solubility follows the order MPEG> HPEG> EPEG according to “cloud point” method. GPC chromatograms confirmed that at RT all PCEs don't decompose in activator

As a primary by-product of the electric arc furnace (EAF) steelmaking process, the relatively low carbonation capacity of EAF slag limits its use as a carbon-sequestering construction material. To address this limitation, this study proposed a two-step chemical-physical modification approach. First, a gas-solid carbonation process was applied, where humidity, temperature, CO₂ concentration, and carbonation

Gaining insights into pedestrian flow patterns in public spaces can greatly benefit decision‐making processes related to infrastructure planning. Interestingly, even pedestrians are unfamiliar with one another, they often follow others, drawing on positive information and engaging in a spontaneous collective behavior of pedestrians. To model this collective behavior, this paper proposed a social force‐based

With the growing emphasis on reducing CO2 emissions, new hydraulic binders are gaining attention. Understanding the hydration products of these new binders is crucial. This study investigates mixed Al/Fe-CO3 AFm hydrates. This research proposes two methods to synthesize CO3-AFm phases with varying proportions of trivalent Al3+ and Fe3+ cations, followed by a thorough characterization of the samples

The performance of microcapsules in terms of "chloride response" and their electrochemical remediation mechanism is investigated. Electrochemical testing methods are used, i.e., kinetic potential polarization and electrochemical impedance testing. The variation rules of corrosion behavior of self-healing cementitious composites with different contents of microcapsules, both intact and pre-damaged,

Understanding the degree of reinforcing bar corrosion in reinforced concrete (RC) structures is crucial for evaluating their residual performance. This study proposes a simulation system for estimating the distribution of corrosion along the rebar of a RC beam member based on surface crack widths. The system integrates the rigid body spring model (RBSM) with machine learning methods. The inputs are

The effect of silica fume (SF) on corrosion depth, mass loss and compressive strength of mortar specimens over time under carbonic acid water environment were studied in this study. In addition, the thermal gravimetric analysis (TG-DTG), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were used to analyze the product evolution and microstructure

The biodeterioration of cementitious materials within sewer networks remains a critical problem that compromises the structural integrity and lifespan of these infrastructures essential to water treatment. This study pioneers the use of micro-Raman spectroscopic mapping, coupled with chemometric tools, to investigate the impact of high H2S levels and bacterial activity on high-resistance cementitious

To mitigate the environmental hazards posed by discarded plastics, polyester fibers produced from such waste have been incorporated into building composites. However, the durability of polyester fibers in cementitious environments is compromised by high alkalinity, which may lead to resource wastage. In this study, polyester fibers were embedded in magnesium silicate hydrate to develop a novel, highly

Accurately predicting the bucket fill rate of excavators is a challenging task due to factors such as material flowability and the complex coupling interactions between the material and the bucket. To address this challenge, this paper proposes a bucket fill rate prediction method based on multi-sensor data fusion and deep learning. The ITCBAM model was developed by integrating a Convolutional Block

Construction scene understanding is the process of perceiving, analyzing, and interpreting three-dimensional dynamic scenes observed through sensor networks, which is usually real-time. The purpose is to understand the construction scene by analyzing the geometric and semantic features of the objects and their relationships. Construction scene understanding is a basic technology for construction automation

Wadangs (a type of eaves tile) are integral components of traditional Chinese buildings and often suffer damage over time, resulting in the loss of pattern information. Currently, AI-based image inpainting methods are applied in pattern restoration, but face challenges in capturing fine textures and maintain structural continuity. This paper proposes a coarse-to-fine image inpainting method based on

Accidents at construction sites are prevalent, posing a significant safety threat to workers. Helmets play a crucial role in protecting workers' heads during accidents, and helmet wearing monitoring is essential for ensuring workers' safety. However, it becomes challenging to detect whether workers are wearing helmets when their heads are obstructed or invisible. To enable continuous and accurate monitoring

Precise three‐dimensional (3D) instance segmentation of indoor scenes plays a critical role in civil engineering, including reverse engineering, size detection, and advanced structural analysis. However, existing methods often fall short in accurately segmenting complex indoor environments due to challenges of diverse material textures, irregular object shapes, and inadequate datasets. To address these

The accurate description of the internal structure of weak interlayers is a prerequisite for the safe construction of deep geotechnical engineering with complicated geological conditions. Geophysical tomography techniques are usually used to detect the mechanical properties and spatial distribution and of deep weak interlayers. However, the mechanical properties of weak interlayers cannot be measured

The collaborative development of underground public spaces (UPS) and urban rail transit (URT) in urban central areas is becoming increasingly common in China. However, the lack of a scientific assessment of collaborative development potential leads to some cities experiencing overdevelopment while others underestimate their development needs. This study addresses this gap by conducting a scientific

This study revisits the coupling effects of tunnel ceiling temperature distribution caused by plume escapes from metro carriage doors during a fire. The impact of fire heat release rates on the ceiling temperature distribution under various door-opening scenarios was analysed by utilising the superposition principle. The concept of virtual fire sources was proposed to model the ceiling temperature

Targeting to sustain the operational safety of tunnels, this paper presents a projection-based approach utilizing large vision model (LVM) inference for efficient and effective multi-class segmentation, including the identification of seepage, in 3D point clouds of tunnels. The proposed approach employs an unsupervised strategy based on point projection and label correction to process input point clouds

Land reclamation from the sea is increasingly common in coastal areas in China as its urban population continues to grow and the construction of subways in these areas becomes an effective way to alleviate transportation problems. Earth pressure balance shield (EPBS) tunneling in reclaimed lands often faces the problem of seawater erosion which can significantly affect the effectiveness of soil conditioning

Earth fissures pose a significant risk to the seismic safety of underground structures at earth fissure sites (USEFs), particularly for large-scale underground frame structures such as subway stations. To date, the failure mechanism of USEFs has only been analyzed qualitatively and requires further comprehensive investigation. Moreover, the existing failure prediction methods for USEFs are complicated

Asset management ensures the safety and longevity of structures through regular maintenance. Reality capture technologies are increasingly being used for asset inspections to obtain information by generating point cloud data, which is becoming more prevalent in tunnel asset management for precise documentation of tunnel geometry and condition. Integrating semantic information from point clouds is crucial

To address the inefficiencies in asphalt pavement modeling and the challenges of integrating design with structural calculations, an automated framework that connects Building Information Modeling (BIM) to the Finite Element Method (FEM) was proposed for evaluating asphalt pavement design solutions and verifying structural optimization. This framework enables precise interaction between BIM and FEM

Precise point positioning is crucial for implementing robotic spot welding. Traditional 2D drawings of structural components lack depth information, making them insufficient for guiding robotic welding. This paper introduces an automated robotic welding framework for spot welding based on 2D drawings and structured light cameras. To enhance the efficiency of point positioning, a new algorithm was also

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For the recycling and reuse of construction waste and scrap tires based on the strategy of limiting carbon emissions in response to warming, a study was performed on the performance of recycled coarse aggregate concrete (RCAC) by replacing natural sand with different volume contents of recycled tire rubber granules (RTRGs) and microencapsulated phase change materials (mPCMs). The results show that

Energy serves as the fundamental driver of material failure, and accurately describing the mechanical properties and energy evolution laws of loaded anchored body is crucial for the stability control of surrounding rock in bolt-supported roadways. Based on uniaxial compression tests of rock samples and utilizing the embedded Fish programming language in FLAC3D, numerical models of loaded sandstone

Slab buckling rockburst is a common form of rockburst under high ground stress conditions, posing a serious threat to engineering safety. Based on the catastrophe model of slab buckling rockburst of surrounding rock, the expressions of control variables of a single rock slab and combined rock slab under quasi-static effect in catastrophe theory are obtained. The tendency of rockburst in the deep-buried

Low-carbon, low-cost, and durable water pipelines are urgently needed for sustainable cities. In this study, low carbon, cost-effective, leakproof Engineered Cementitious Composites (ECC) pipes were developed benefiting from the proposed ECC pipe design model and material innovation. The proposed model has been experimentally validated on ECC beam and ECC pipe. The developed desert sand Engineered

Embedding rebars in 3D printed engineered cementitious composites (3DP-ECC) promises to improve the structural toughness and loading capacity, while a robust bond between them is critical for digital construction with reinforcements. This paper presents a series of pull-out tests on the bond behaviour between rebars and 3DP-ECC to investigate the effects of variable rebar arrangement direction, diameter

Engineered cementitious composites (ECC), known for their strain-hardening behavior and multi-cracking characteristics, were ideal materials for energy dissipation. An energy dissipation wall (EDW) constructed from ECC materials and assembled into reinforced concrete (RC) frame structures formed a novel type of prefabricated ECC-EDW-RC frame structure. In this study, ECC-EDW-RC frame specimens were

Ultra-high-performance concrete (UHPC) is renowned for its exceptional strength and durability, but the undesirable high material cost due to the considerable expense of reinforcing steel fiber hinders its wide application. The incorporation of more sustainable and light synthetic fibers presents a promising avenue for lowering the price and weight of UHPC while affecting the rheological and hardened

Lighting on/off control is the most crucial method of interior lighting control, with numerous automated and intelligent on/off control strategies being researched and developed. Currently, these strategies are primarily aimed at energy savings rather than creating a satisfactory optical environment. This paper introduces a novel on/off control method based on the subset sum model, primarily aimed

To address the escalating thermal risks and suboptimal cooling capacity distribution of centralized refrigeration systems in large-width faces, this study developed a specialized “high-efficiency air cooler for working faces” and introduced an innovative cooperative cooling strategy integrating air coolers, dust suppression water, and emulsion (A-D-E system). Numerical simulations and field measurements

Tunnel fires have become a huge threat to human life and property, and the large amount of smoke and thermal produced by the fire is the principal cause of human casualties. The water mist system is considered a highly promising fire extinguishing technology. However, the research on the water mist system which could simultaneously extinguish fire and block smoke is rare. The objective of this study

The Bingham model is generally used to describe the flow of cement-based materials, and its parameters, such as yield stress and plastic viscosity, are measured using a rheometer. However, the rheological measurement does not provide the unique Bingham parameters for a single material when rheometers take different rheological geometries or measuring protocols. This study constructs a model that can

The application of titanium dioxide (TiO2) coating in cement-based materials faces challenges regarding its durability. This study presented the concept of ‘induced bonding’ for enhancing coating adhesion. By modifying TiO2 with CaO, nucleation sites were constructed on its surface, inducing the growth of hydration products and connecting the catalytic materials to the substrate. As a result, a novel

In the Architecture Engineering & Construction (AEC) industry, how design behaviors impact design quality remains unclear. This paper proposes an approach that firstly unveils and quantitatively describes the relationship between design behaviors and design quality based on Building Information Modeling (BIM). Real-time collection and log mining are integrated to collect raw data related to design

Field transport productivity analysis is crucial for scheduling large-scale earth–rock works. Although camera surveillance facilitates the monitoring of transportation activities, disjoint views from sparse cameras result in discontinuous monitoring. To address this issue, a single-camera tracking with cascade R-CNN is used for target detection, and an improved TransReID for appearance feature extraction

Highway interchanges have traditionally been designed through a time-consuming manual process. To enhance efficiency and effectiveness, this paper develops an objective-directed automatic and intelligent interchange design method using graph conditional variational autoencoder. Based on interchange graph representation and augmentation techniques, data are collected from diverse interchanges types

Buried object detection using ground penetrating radar (GPR) benefits from deep neural networks but still faces the problem of condition- and question-limited outputs. This paper presents an approach to conduct “one-for-all” (OFA) tasks in GPR data processing. In the approach, a generative pre-trained transformer (GPT) generates the prompts based on input GPR data and an open-ended question. The question

This paper presents a powertrain integrated with an energy regeneration system designed to decrease energy consumption and emissions in hybrid hydraulic excavators. The feature of this powertrain is its integration of a hydrostatic transmission (HST), which optimizes torque and speed between the pump and power sources. Additionally, the energy regeneration system includes two distinct methods: employing

Autonomous material transportation robots offer an efficient solution for moving goods at construction sites, delivering tools, building materials, and supplies to precise locations. The integration of these robots with various types of carts commonly used on construction sites could significantly ease operational requirements, reducing the cost of robotic adoption to a level more feasible for construction

Hybrid metamaterial employing the local resonance and porous material will effectively promote vibration and wave attenuation. This study specifically investigated the vibration attenuation capabilities of metamaterial made of expanded polystyrene (EPS) foamed cementitious (EFC) material and local rubber-mass resonators. Four variations of EFC, differing in density, and three types of local resonators

Recent studies have demonstrated the effectiveness of Fibre Reinforced Polymer (FRP) and steel bars as longitudinal reinforcement for Geopolymer Concrete (GPC) beams. However, research on the combined performance of these materials in hybrid FRP/steel-reinforced GPC (HRGPC) beams remain limited. This study addresses this gap using finite element (FE) analysis with ABAQUS software and theoretical modeling

The urban heat island (UHI) effect significantly impacts urban environments, driving the need for innovative cooling strategies. Reflective cementitious composites, with their potential to reduce solar heat absorption, offer a promising approach to mitigating UHI effects. This review explores factors influencing the reflectance of cementitious composites, including aggregate types, supplementary cementitious

This study focuses on the composite cementitious materials containing recycled brick powder (RBP) with different Portland cement contents. The effect of RBP on the hydration mechanism of cement-based materials is studied by constructing RBP-cement composite cementitious materials. The hydration products of the composite cementitious materials are analyzed. The hydration thermodynamic model of the composite

Prefabricated steel structures with bolted-angle connections are effective in resisting progressive collapse due to their high load-bearing and rotational capacities. This study investigates the tensile properties of these connections under ambient and high-temperature (500 °C and 800 °C) steady-state tests. A total of 30 tensile tests with various parameters, such as angle thickness, gauge length

In the process of rock breaking by a TBM (Tunnel boring machine), the particle size distribution of rock chips is affected by both rock lithology and TBM operational parameters, showing typical variability and inhomogeneity. Multifractal theory can describe the variability and inhomogeneity of the particle size distribution of rock chips more comprehensively. Therefore, this study attempts to quantitatively

A novel C-type flocculation reagent was developed to address the high water content of sludge and the environmental pollution caused by wastewater discharge during mechanical dewatering in the Zhanjiang Bay undersea tunnel. Microscopic parameters, such as particle size and zeta potential, were analyzed to elucidate the flocculation and dewatering mechanisms of the C-type reagent. The applicability

A 3D numerical model of distributed fault is established in this paper. Considering both strike-slip and dip-slip, the stress evolution and spatial–temporal migration characteristics of surrounding rock at different creep-slip times and depths are analyzed during creep-slip. The failure approach index (FAI) was employed to assess the failure degree. The results show that the shearing and squeezing

To evaluate and optimize the screening characterization of double-deck vibrating screen of slurry TBM tunnelling, a three-dimensional (3D) coupled model of vibrating screen was established based on an integrated CFD-DEM-FEM method in this paper. The transport characteristics of particles and the fluidity of slurry were revealed, and the kinetic response of the screen surfaces was comprehensively analyzed