Electromagnetic self-curing is an emerging internal heating technology that uses the electrical conductivity and magnetic susceptibility of steel reinforcement to generate heat, enabling uniform and efficient curing of concrete. This study presents a novel electromagnetic self-curing (ESC) strategy designed to address the challenge of insufficient early-age bond performance at the steel-concrete interface during winter construction. Controlled pull-out tests, microstructural characterization, and Multiphysics simulations with COMSOL were conducted to clarify the coupled heat transfer and interfacial bonding mechanisms under target temperatures of 40 degrees C, 50 degrees C, and 60 degrees C and a range of curing ages. The results show that ESC substantially increases the internal temperature of concrete and reduces thermal gradients, with a target temperature of 50 degrees C providing the highest heating efficiency and bond strength improvement. Under these conditions, one-day bond strength increased from approximately 2 MPa in standard curing to about 16 MPa. Microstructural analyses revealed that moderate temperatures accelerate hydration, produce denser interfacial transition zones, and improve pore structure, while excessive heating at 60 degrees C can lead to structural inhomogeneity. The combined experimental and numerical approach demonstrates that ESC is a low-energy and high-efficiency method for improving the early-age performance of reinforced concrete in cold climates, offering both theoretical and practical foundations for broader engineering application.

The cement industry is a major source of global CO₂ emissions, and limestone calcined clay cement (LC³) is a promising low-carbon alternative, but its large-scale application is limited by the dependence on high-cost commercial calcined clays. Coal gangue (CG) is a massive industrial solid waste with potential pozzolanic activity after thermal activation, yet its reaction behavior, synergistic mechanisms, and performance equivalence to commercial calcined clays in LC³ systems remain unclear, with a lack of quantitative assessment of its carbon emission reduction potential. To address these gaps, this study conducts a multi-scale investigation on thermally activated coal gangue (CCG)-based LC³ cement, combining experimental characterization including X-ray diffraction, thermogravimetric analysis, scanning electron microscopy, mercury intrusion porosimetry, isothermal calorimetry and life cycle assessment. The results show that the optimal mass ratio of CCG to limestone is 2:1, and the LC³ formulation with 20% CCG replacement achieves a 28-day compressive strength comparable to that of commercial calcined clay-based LC³ and ordinary Portland cement. A synergistic reaction mechanism involving sulfate, carbonate, and aluminosilicate is clarified: gypsum regulates early aluminate hydration, while limestone reacts with reactive aluminates derived from CCG to form stable carboaluminate phases, which refine the pore structure and densifying the microstructure. LCA results indicate that the optimal CCG-based LC³ formulation reduces the global warming potential by 24.4% compared to ordinary Portland cement. This study realizes the high-value utilization of CG and provides a low-cost, sustainable alternative to commercial calcined clays for LC³ technology, offering technical support for the decarbonization of the cement industry and the disposal of industrial solid waste.

Microencapsulated phase change materials (MPCMs) offer a promising way to enhance the thermal performance of cement-based materials; however, their incorporation often compromises mechanical properties and durability, limiting practical application. A mechanistic understanding of how MPCM particle size governs the coupled thermal, mechanical, and transport behavior of cementitious systems remains incomplete. In this paper, two organic MPCMs with identical core–shell chemistry but distinct particle sizes (mean diameters of 10.78 μm and 34.21 μm) were incorporated into mortar at dosages of 10 wt.% and 20 wt.% under w/b ratios of 0.35 and 0.45. The effects of MPCM particle size and content on hydration kinetics, rheology, strength development, pore transport behavior, and thermal conductivity were systematically investigated using isothermal calorimetry, flow spread testing, compressive strength measurements, capillary water absorption, thermal conductivity analysis, X-ray diffraction, and SEM–EDS characterization. Results show that MPCM incorporation delays early-age hydration and reduces peak hydration rates, with finer particles exerting a stronger inhibitory effect due to increased specific surface area and water adsorption. While all MPCM-modified mortars exhibit reduced compressive strength and increased capillary absorption, larger MPCM particles mitigate strength loss by limiting the total interfacial transition zone (ITZ) area and reducing ITZ connectivity. In contrast, smaller MPCM particles more effectively decrease thermal conductivity, achieving up to a 33% reduction, owing to enhanced interfacial thermal resistance. Microstructural observations confirm that MPCMs do not alter cement hydration products but influence performance through interfacial defects, porosity evolution, and particle-scale interactions. These findings demonstrate that MPCM particle size critically controls the trade-off between thermal regulation and structural integrity, providing quantitative guidance for designing PCM-modified concrete through optimizing particle-size.

The rapid expansion of China’s immersed tunnel construction has resulted in substantial consumption of reinforced concrete and construction energy, thereby generating considerable greenhouse gas (GHG) emissions during the construction stage. Unlike conventional tunnels, immersed tunnels require large cross-sectional dimensions, complicated geological conditions (e.g., varying seabed burial depth and settlement grade requirements), and unique structural parameters, leading to distinct emission characteristics that are currently insufficiently understood. To address this gap, this study aims to quantify construction-stage GHG emissions of immersed-tube segments, identify key influencing factors linking construction parameters and material input with GHG emissions, and develop simplified predictive models for design-stage estimation. A total of 51 immersed-tube segments from three representative cross-sea tunnel projects in China were examined. Under a unified system boundary and functional unit (covering material production and processing, material transportation, and on-site construction energy consumption), the life-cycle assessment (LCA) framework was applied to quantify the construction-stage emissions of each immersed-tube segment. The construction-stage GHG emissions of a single segment range from 1.56 × 104 to 2.71 × 104 t CO2 eq (mean ≈ 2.40 × 104 t CO2 eq). Correlation and partial correlation analyses demonstrated that the total mass of construction materials exhibits the strongest correlation with GHG emissions, followed by the element volume, concrete cross-sectional area, settlement grade, and burial depth. The results further indicate that material intensity is the dominant determinant of GHG emissions for immersed tubes, while the effects of seabed and settlement conditions mainly operate through structural scale and material demand. Finally, two linear regression models were developed, and the model based on total material mass provides the most accurate prediction of construction-stage emissions. The immersed-tube volume can be used to estimate approximate GHG emissions at the design stage, whereas the total material mass serves as a better predictor when detailed material input data are available. This study is based on segment-level data from three Chinese projects and focuses on the construction stage; therefore, transferability requires further validation. Material intensity is the dominant determinant, and the total-material-mass model is the most accurate predictor.

The accumulation of coal gangue (CG) poses severe environmental hazards, largely due to its low valorization rate. This study investigates the enhancement of mechanical properties of low-carbon cementitious composites incorporating microwave-activated CG under microwave curing. The CG was activated using various microwave heating regimes, and the resulting pozzolanic activity was assessed through both direct and indirect methods. Cementitious composites with microwave-activated CG were subjected to different microwave curing regimes. Their mechanical properties, hydration products, and pore structures were analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR). The results show that microwave activation at 800 °C for 20 min provides the highest pozzolanic activity of CG, with the pozzolanic activity index reaching 70.91

Coal gangue (CG), as a major solid waste byproduct of the coal industry, has attracted widespread attention due to its potential in construction materials. This review systematically evaluates the activation mechanisms and engineering performance of CG, exploring the impact of various activation methods such as thermal, mechanical, chemical, microwave, and synergistic activation on its hydration potential. The findings suggest that activated CG can significantly enhance the cementitious performance of cement-based materials, reduce cement consumption, and contribute to sustainable construction practices. Thermal activation enhances CG reactivity by removing combustible components and transforming mineral phases, while mechanical activation increases the specific surface area through fine milling. Chemical activation, using alkaline or acidic activators, promotes the formation of hydration products by depolymerizing silica-aluminate networks, and microwave activation rapidly enhances reactivity by converting electromagnetic energy into thermal energy. When used as a supplementary cementitious material, activated CG improves durability, but may also affect workability and mechanical properties. When used as an aggregate, CG’s high water absorption and low elastic modulus can lead to increased shrinkage and reduced freeze-thaw resistance, requiring strict control of the substitution ratio. Future research should focus on optimizing activation methods to enhance CG’s reactivity and performance, while addressing challenges related to its high water absorption and variable mineral composition. Additionally, a life cycle assessment of CG utilization in construction materials should be conducted to comprehensively evaluate its environmental impact.

The utilization of precast reinforced concrete frames is widespread in the construction industry. However, among all components of the frame structure, the joint is considered the most vulnerable and critical during horizontal seismic activity. This study aims to investigate the seismic performance of the joints of an I-shaped assembled monolithic column, a T-shaped assembled monolithic column and a T-shaped fully precast assembly column. This investigation studies the failure mode, crack pattern, strain curve, load-displacement curves, characteristic point and ductility, load-bearing and deformation capacity, strength and stiffness degradation, and energy dissipation capacity of the joints. The findings reveal that the I-shaped column frame joint experiences shear failure, while the T-shaped column frame joint fails at the ends of the beams. Stiffness degradation of column frame joints with the same cross-section is found to be similar. The assembled monolithic beam-column joint displays significant vertical interface cracking after prefabrication and casting, with a gradual decrease observed in the skeleton curve. In contrast, the T-shaped fully precast assembly column frame joint shows weak plastic deformation capacity at the beam hinges, leading to significant angle slip during bending failure and a severe pinching phenomenon in the hysteresis curve. Furthermore, the T-shaped column flange, compared to the Ishaped column section, increases the joint height and substantially enhances its shear bearing capacity, albeit at the expense of weakened bending bearing deformation capacity. This study develops an assembly connection method suitable for the special-shaped precast column-frame structural system.

Lithium slag (LS), an industrial by-product of lithium extraction, has potential as a supplementary cementitious material (SCM) to reduce carbon emissions. However, its use as a cement substitute lowers early strength, and the relationship between microstructure and mechanical properties, particularly under microwave curing, is not well understood. This study compares the reactivity of acid-extracted lithium slag (A-LS) and alkali-extracted lithium slag (K-LS) as SCM and investigates the effect of microwave curing on LS hydration in cement-based materials. COMSOL Multiphysics (R) finite element simulations were used to optimize the microwave curing process and examine its impact on material properties and microstructure. Hydration was analyzed using thermogravimetric analysis (TG/DTG) and X-ray diffraction (XRD), while microstructure and pore structure were characterized using scanning electron microscopy (SEM) and mercury intrusion porosimetry (MIP). The results show that, under standard curing, K-LS achieved 53.5 MPa at 28 days, a 20 % increase over A-LS, due to its pozzolanic reactivity and pore-filling effects. Microwave curing accelerated hydration, with K-LS samples reaching 34.5 MPa early strength (a 55 % increase) and 60.8 MPa late strength (a 50 % increase), approaching pure cement strength. Finite element analysis revealed that 300 W microwave power ensures uniform heating and optimal curing, while higher power causes uneven electromagnetic distribution, local overheating, and potential material damage. Microstructural analysis confirmed that microwave curing promotes dense C-S-H gel formation, reduces porosity, and significantly improves material performance. This study demonstrates that LS, combined with microwave curing, not only enables efficient resource use and reduces environmental impact but also enhances cement-based material performance, providing key support for low-carbon construction.

Manufactured sand (MS) is increasingly utilized in construction for its strong mechanical properties and low environmental impact. However, optimizing the mixtures of manufactured sand concrete (MSC) is complex due to the variability in MS properties and the need to balance multiple objectives, such as uniaxial compressive strength (UCS), CO2 emissions, and cost. This study proposes a multi-objective optimization (MOO) method based on machine learning (ML) and the non-dominated sorting genetic algorithm II (NSGA-II) to optimize MSC mixtures. The results indicate that the extremely randomized trees (ERT) model exhibits the best predictive performance for UCS, with an R value of 0.988 on the test set. The SHapley Additive exPlanations (SHAP) analysis identifies that the UCS is most sensitive to water-binder ratio (W/B), curing age and the maximum diameter of coarse aggregates. The developed MOO model effectively identifies the Pareto front, balancing cost, UCS, and CO2 emissions for MSC mixtures. By offering a systematic approach to optimizing MSC design, this framework enables cost-effective and sustainable concrete production, supporting the development of environmentally friendly construction practices.

Lightweight wood structural systems represent a sustainable building approach, characterized by a high prefabrication and favorable energy efficiency. Within such systems, wood shear walls serve as the primary lateral force-resisting components, providing essential resistance against seismic and wind loads. This study proposes an innovative composite joint that combines nail fasteners with silicone strips, offering a new strategy for enhancing the structural performance of wood shear walls. Using an integrated experimental and numerical simulation approach, the mechanical behavior of the novel joint and the lightweight wood shear walls incorporating such connections was systematically investigated. First, monotonic loading tests were conducted on 140 specimens of three joint types: conventional nailed joints, nail-silicone strip composite joints, and pure silicone strip joints. The mechanical performance of each type was compared and analyzed. Subsequently, monotonic and quasi-static tests were carried out on wood shear walls with conventional nailed joints and those with the nail-silicone strip composite joints, comparing their bearing, deformation, and energy dissipation capability. The results confirmed the superior mechanical performance of walls with the composite joints. Finally, a finite element model of wood shear walls was developed, and a parameter analysis was performed on shear walls with different types of nail-silicone strip composite joints. The findings demonstrate that the proposed composite joint and the corresponding wood shear walls exhibit excellent mechanical performance, highlighting the advantages of the new joint in terms of load resistance and providing a theoretical basis for their engineering applications.

Cementitious binders, characterized by their porosity and high content of portlandite, are capable of reacting with CO2 to produce carbonate compounds that possess binding properties. This study explores the carbonation curing process in cement-based materials, where CO2 reacts with cement to form CaCO3, using molecular dynamics and density functional theory simulations. The focus is on analyzing the effects of pore size, humidity, and temperature on CO2 diffusion, adsorption, and reaction efficiency. Results show that larger pores (e.g., 24 & Aring;) enhance CO2 consumption, with ratios of 0.334 and 0.381 under dry and humid conditions, while smaller pores (e.g., 8 & Aring;) limit CO2 entry. Additionally, water molecules under humid conditions significantly hinder CO2 diffusion, with the self-diffusion coefficient decreasing by approximately 30 % compared to dry conditions. However, larger pores alleviate this hindrance, providing an additional diffusion pathway for CO2. Although increasing the temperature (up to 700 K) enhances CO2 diffusion, it reduces the adsorption rate, leading to a significant decrease in the CO2 consumption ratio. The study also develops a linear regression model between CO2 consumption ratio and the square root of time, further revealing the kinetic characteristics of CO2 consumption during the carbonation curing process. The reaction between CO2 and Ca(OH)2 is thermodynamically spontaneous under both dry and humid conditions, with the Gibbs free energy being lower in the humid environment, indicating that water molecules stabilize the reaction products and enhance the carbonation reaction at low temperatures. These findings provide important theoretical support for optimizing the carbonation curing process, contributing to the improvement of concrete performance and the reduction of the carbon footprint in the cement industry.

The cement industry is one of the major sources of global carbon dioxide (CO2) emissions, and sustainable solutions are urgently needed to reduce its environmental impact. This study focuses on the synergistic effects of thermally activated coal gangue powder (ACGP) and limestone powder (LSP) in enhancing the mechanical properties and microstructure of composite cementitious materials. Experimental techniques such as thermogravimetric analysis (TGA), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), hydration heat tests and scanning electron microscopy (SEM) were used to systematically study the thermal activation mechanism of ACGP and its effects on cementitious properties. The results show that ACGP achieves optimal pozzolanic activity when calcined at 700 degrees C for 1 h. Using a mix proportion of 70 % cement, 20 % ACGP and 10 % LSP, the limestone calcined coal gangue based cementitious materials achieved a 28-day compressive strength of 44.14 MPa, which is 19.8 % higher than the group without LSP and comparable to ordinary Portland cement (OPC). Compared to OPC, this mixture reduces CO2 emissions by 18.5 % and production costs by 13 %, while also outperforming limestone calcined clay cement (LC3). These findings demonstrate that the limestone calcined coal gangue based cementitious materials is an environmentally friendly and cost-effective alternative to traditional cement, providing essential technical support for sustainable construction practices.

The use of recycled coarse aggregates (RCA) in concrete production offers significant environmental and economic benefits. However, the high water absorption and low mechanical strength of RCA, caused by residual mortar and internal cracks, severely limit its application. This study employed microbial-induced calcium carbonate precipitation (MICP) technology to improve RCA performance, systematically investigating the effects of key parameters such as bacterial strains, bacterial concentration, modification duration, and urea addition sequence. This study employed microbial-induced calcium carbonate precipitation (MICP) technology to enhance the performance of RCA. The investigation systematically examined the effects of key parameters, including bacterial strains (Bacillus subtilis, urease mixed bacteria, and Bacillus pasteurii), bacterial concentrations (0, 2.4 × 107 cells/mL, 9.3 × 107 cells/mL, 2.49 × 108 cells/mL, and 2.36 × 109 cells/mL), modification durations (0 d, 3 d, 7 d and 14 d), and urea addition sequences (urea added to the calcium source, urea added to the culture medium, and added to the bacterial solution followed by 2 h of incubation). The impact of MICP treatment on RCA’s water absorption, apparent density and resistance to ultrasonic impact was analyzed. Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD) were used to characterize the microstructure and composition of calcium carbonate deposits, revealing the mechanisms by which MICP enhances RCA performance. The results showed that optimized MICP treatment reduced RCA water absorption by 32.5%, with the optimal conditions being a bacterial concentration of 2.4 × 107 cells/mL, a modification duration of 7 days, and a two-hour urea resting period. It is primarily due to calcium carbonate filling pores and sealing cracks, which significantly improves the structural integrity of RCA. This study demonstrates that MICP is an effective and sustainable method for RCA modification, providing theoretical support and practical insights for the recycling of construction waste and the promotion of green building materials.

Understanding the deterioration mechanisms of Fiber-Reinforced Geopolymer Mortars(FRGC) under aggressive environments is essential for developing sustainable alternatives to Portland cement. Although fibers can enhance the performance of geopolymer Composites, there is limited research on the types of fibers and their optimal proportions. Additionally, studies on the durability of FRGC under the coupled effects of chloride salt solution corrosion and wet-dry cycling are still relatively scarce. This study systematically adjusts the type and proportion of fibers to determine the optimal mix design, while analyzing the effects on both the macroscopic strength and micro-structure of the material under chloride salt solution corrosion and wet-dry cycling. A coupled diffusion model based on COMSOL was established to verify the accuracy and practicality of the results. Experimental results show that when the total fiber content is 2 %, a 1:1 ratio of Polyethylene (PE) fibers to steel fibers significantly reduces the brittleness of the material while improving its strength. Analysis of the corrosion caused by different concentrations of sodium chloride solutions, coupled with wet-dry cycling tests, reveals that the formation of Sodium Aluminosilicate Hydrate (N-A-S-H) and Calcium Silicate Hydrate (C-S-H) gels leads to densification of the matrix, resulting in enhanced initial compressive and bending strength. However, after prolonged exposure, the precipitation and dissolution of calcium chloride phases induce internal expansion and micro-cracking, ultimately destroying the strain-hardening characteristics of the material. This study clarifies the dynamic evolution of FRGC under coupled chemical and physical stresses, providing a knowledge base for the design of corrosion-resistant cement-based composites in marine and saline environments.

The ultimate bearing capacity of reinforced concrete beams after exposure to fire is investigated in this study through the utilization of numerical simulation, regression fitting, and machine learning techniques to examine the thermal and mechanical properties of such beams under high temperatures. In this study, a series of fire and static load tests are conducted on seven reinforced concrete T-beams. Based on the experimental observations and considering the effects of high-temperature concrete spalling and steel/concrete bond degradation, a numerical model is developed to simulate the temperature distribution and structural behavior of reinforced concrete T-beams. The accuracy of the numerical model is validated by comparing the cross-sectional temperature profiles and ultimate bearing capacities after fire exposure with experimental results. A dataset comprising 500 samples is established, with variables including fire exposure time, depth of concrete spalling, spalling area ratio, and loading conditions. Regression fitting and machine learning techniques were employed to establish predictive formulas and models for estimating the ultimate bearing capacity of reinforced concrete T-beams after fire exposure. The accuracy of both methods is found to be within 10%.

This study aims to apply microwave-activated coal gangue (MCG) to develop limestone calcined clay cement (LC3). The impact of microwave activation schemes (microwave temperature and holding time) on the pozzolanic activity of coal gangue were explored. After that, LC3 cements were prepared by replacing cement clinker with limestone powder (LS) and MCG at different ratios. The uniaxial compressive strength, phase composition, microstructure, and pore structure of the MCG-based LC3 cements were analyzed. The results indicate that the maximum volcanic ash activity index is achieved when the material is microwave-activated at 800 degrees C with a holding time of 20 min. The MCG based LC3 cements achieve the highest strength at an MCG content of 20 % with an MCG:LS ratio of 2. Then, the response surface methodology was employed to predict the optimal mixture proportions for achieving the best strength of the material. The life cycle analysis shows that the carbon emission of the MCG-based LC3 material is 30 % lower than that of Ordinary Portland Cement. This study develops a new high-performance material with low carbon emission for construction industry.

Hydraulic fracturing using micro-particles is an effective technology in the petroleum industry since the particles facilitate crack propagation of the shale layer, creating pathways for oil and gas. A new kind of polymer-coated ceramsite particles (PCP) was generated. The friction and wear properties of the particles under different loads and speeds were also studied. The tribological relationship between the newly fabricated polymer-coated ceramsite particles and the fracturing fluid was studied through tribological experiments under the condition of fracturing fluid lubrication. The results show that, in contrast, the wear of the new-generation particles is relatively stable, indicating that it has good adjustable friction properties. In addition, under the lubrication condition of fracturing fluid, the new-generation particles have better hydrophobicity, high-pressure resistance, and low reflux rate, which have an important value as a practical engineering application for improving shale gas production efficiency and production.

The precast segmental self-centering concrete-filled steel tube (PSCFST) bridge is not only the ideal choice for fast and environmentally friendly construction but also has good seismic and resilience properties. Our research group has carried out shaking table test research on the PSCFST bridge, but due to the limitation of test equipment and site, no damage test has been carried out. To further study the seismic performance of PSCFST bridges when subjected to larger ground motions, machine learning (ML) models are developed to predict the seismic performance of PSCFST. A novel combined prediction model based on Conv1D-LSTM was proposed to predict the PSCFST bridge acceleration response. Two other commonly used ML methods including XGBoost and Random forest regression (RFR) are also used for comparison purposes. A database of ML prediction models is established based on 116 sets of input ground motion (GM) and superstructure acceleration response from shaking table tests. Then, the data of RSN292 60% GM were selected as the prediction test data. Furthermore, based on the Opensees platform, the PSCFST fiber finite element (FFE) model was established and validated by the shaking table test results, then the dynamic time history analysis of the ground motion with larger amplitude (greater than the input ground motion assignment of the shaking table test) was carried out. The superstructure acceleration response of 70%–120% of the RSN 292 GM is obtained by the FFE model and used as the data set for the ML prediction model. After that, the superstructure acceleration response is obtained through three prediction models. Comparing the simulation and prediction results shows that all the Conv1D-LSTM, XGBoost, and RFR models can reliably predict the acceleration response of the PSCFST bridge. In all cases, the Conv1D-LSTM model performed outperforms the XGBoost and RFR models. The determination coefficients (R2) of Conv1D-LSTM, XGBoost, and RFR model for the prediction of superstructure response are 0.9643, 0.8780, and 0.9623, respectively.

In order to study the thermal properties and static performance of reinforced concrete (RC) beams exposed to fire and reveal the relationship between fire exposure time, concrete spalling, bond slip and mechanical properties, the numerical simulation, theoretical analysis and machine learning methods were adopted to study the effects of high temperature on thermal and static mechanical properties of RC beams and the prediction methods of residual bearing capacity were proposed in this paper. Fire tests and static load tests after natural cooling were carried out on 4 RC simply supported beams. The refined numerical analysis model of RC beam was established and its validity was verified by the fire test. The effects of fire exposure time and characteristic parameters of concrete spalling on temperature fields and interfacial bond properties were simulated and analyzed. The residual flexural capacity were calculated and compared with measured and simplified theoretical values. Finally fire exposure time, concrete spalling depth and local spalling area ratio were selected as variables to design 250 groups of sample data, and sample database was established based on the refined numerical analysis model. Several methods for predicting residual flexural capacity after fire were proposed. Their accuracy and reliability were compared and analyzed, which can provide a method reference for safety estimation and analysis of post-disaster engineering.

As a lightweight cementitious material for thermal insulation, the mechanical performance of foamed geopolymer is always compromised by its density reduction. In this study, recycled-glass-fiber-reinforced plastic (rGFRP) fiber was used to reinforce the fly ash-slag based foamed geopolymer, and vitrified micro bubbles (VMB) were applied to further decrease the thermal conductivity and modify the resistance of the lightweight mortar against drying shrinkage. The results revealed that the density, compressive strength, and thermal conductivity of the foamed geopolymer with/without VMB decreased with the increase in foaming agent content. By adding 2~6% of rGFRP fiber, the compressive strength was increased by 25~165%, and the drying shrinkage was reduced the most, by 55%. After the addition of 10% of VMB, the density, thermal conductivity, and drying shrinkage of foamed geopolymer mortar were further decreased, with the highest reductions of 8%, 26%, and 64%, respectively, due to the reduced pore volume and increase proportion of closed pores. With 6% of rGFRP fiber and 25% of foaming agent, the lightweight geopolymer mortar had the optimum performance, with compressive strength of 1.343 MPa, thermal conductivity of 0.134 W/(m·K), and drying shrinkage of 0.095%. This study developed a sustainable lightweight mortar with multiple types of industrial by-products, which benefit both the development of thermal insulation materials and reuse of solid wastes.