最新刊期
卷 48 ， 期 3 ， 2026
- 摘要：In engineering practice of microbial-induced carbonate precipitation (MICP), urease-producing bacteria (UPB) cannot tolerate high-salt concentrations of cementation solution (CS). Increasing the salt tolerance of UPB to CS can improve the efficiency and the application scope of MICP. In order to enhance the salt tolerance of Sporosarcina pasteurii, a gradual salt concentration gradient method was employed for its domestication. Growth characteristics in the domestication medium were evaluated through optical density tests, revealing a slowed growth rate in domesticated bacteria. Furthermore, salt tolerance tests, unconfined compressive strength (UCS) tests, and scanning electron microscopic analyses were conducted to investigate the calcium ion precipitation capacity, strength properties of bio-cemented sand columns, and microstructure of reinforced samples among untamed bacteria (UB), domesticated bacteria (DB), and the control group. The results indicate the following: DB's tolerance to CS salt concentration exhibited an approximate increase of 0.25 mol/L. In the context of high concentration CS conditions, DB-treated samples demonstrated approximately double the UCS in comparison to UB, indicating a more efficient calcium ion precipitation process. Furthermore, DB resulted in a higher proportion of cauliflower-like calcium carbonate crystals under high concentration CS conditions. This crystal morphology is commonly associated with superior mechanical properties. These findings demonstrate that domestication effectively enhances bacterial biomineralization performance in high-salinity environments.关键词：microbial-induced carbonate precipitation (MICP);bacteria domestication;salt tolerance of bacteria;calcium utilization rate;unconfined compressive strength (UCS);cementation solution concentration31|9|0更新时间：2026-06-09
- 摘要：Both calcium source and admixture have an impact on the reinforcement effect of microbial induced calcium carbonate precipitation (MICP). In order to explore the effects of different concentrations of the admixture (AlCl3∙6H2O) and calcium sources on the curing effect of MICP, the sand column test and aqueous solution test were carried out, and different concentrations of AlCl3∙6H2O were added to the cementing solution for perfusion test, and the unconfined compressive strength (UCS) and calcium carbonate content after reinforcement were measured. The MICP reinforcement effects of calcium chloride and calcium acetate were analyzed, and the improvement of MICP reinforcement effect under different concentrations of AlCl3∙6H2O for the two calcium sources was analyzed. The effect of aluminum ions on the composition and morphology of calcium carbonate was analyzed with SEM. The results showed that calcium acetate as a calcium source had a better curing effect. After the addition of aluminum ions, the strength optimization effect of calcium chloride as a calcium source was more obvious. Among them, the concentration of AlCl3∙6H2O at 6 mmol/L was the optimal concentration, which was conducive to reduce the number of perfusions, saving raw materials and reducing economic costs. Aluminum ions contribute to the formation of calcium carbonate crystals, enhance the adsorption of sand particles, and improve the curing strength. The concentration of aluminum chloride has a significant effect on the curing effect of MICP with different calcium sources, which is of great significance for engineering practice.关键词：microbial induced calcium carbonate precipitation (MICP);aluminum chloride;calcium chloride;calcium acetate;unconfined compressive strength18|6|0更新时间：2026-06-09
- 摘要：Enzyme-induced calcium carbonate precipitation (EICP) is a soil solidification and improvement technique with broad prospects. In order to study the mechanical fracture mechanism and meso-properties of EICP stabilized sand, this paper, based on PFC2D, studies the mechanical parameters, particle displacement and microcrack development process of cemented sand samples with different cementation levels and different calcium carbonate distributions in uniaxial compression tests to explain their deformation and failure mechanisms and failure evolution laws. The results indicate that discrete element simulation considering the content, distribution, and particle contact model of calcium carbonate can better reflect the mechanical and deformation characteristics of the cemented sand specimens compared with laboratory tests. Specimens with a low level of cementation undergo local shear failure, and the failure surface emerges in areas with lower calcium carbonate content in the middle. With an increase in cementation level, average particle displacement in sandy soil becomes smaller, and the direction of particle displacement is closer to the axial compression direction of the specimen, leading to splitting failure with better global stability. The higher the level of cementation is, the more uniform the distribution of particle contacts in specimens is observed, resulting in slower extension rates for both crack growth and zones experiencing cementation failure.关键词：enzyme-induced calcium carbonate precipitation (EICP);sand soil solidification;discrete element simulation;uniaxial compression test32|4|0更新时间：2026-06-09
- 摘要：As industrialization accelerates, the pollution problem of Zn2+ is becoming increasingly severe, posing a significant threat to the stability of ecosystems and engineering structures. To cope with this challenge, this study examines the solidification effect of MICP (Microbially Induced Carbonate Precipitation) synergized with magnesium oxide on Zn2+ contaminated red clay. The variation of unconfined compressive strength (UCS) and shear strength index of solidified soil under different concentrations of cementation solution, magnesium oxide contents and Zn2+ concentrations were investigated by UCS tests and direct shear tests. The curing effect of MICP synergized with magnesium oxide technology on Zn2+ was analyzed by ion occurrence form test and pH value changes of samples before and after curing. The results show that the incorporation of magnesium oxide significantly improves the UCS and shear strength of Zn2+ contaminated red clay. When the content of magnesium oxide is 5%, the utilization rate is the highest. When the concentration of cementation solution is 1.0 mol/L, the UCS and shear strength are the highest. The shear strength index of solidified samples is mainly affected by the content of magnesium oxide. The incorporation of magnesium oxide facilitates calcium carbonate precipitation during MICP by increasing the pH value. This process accelerates the transformation of zinc ions from a weak acid-extractable state to reducible, oxidizable, and residual states.关键词：microbial mineralisation;magnesium oxide;red clay;strength characteristics;microbial induced carbonate precipitation (MICP)27|2|0更新时间：2026-06-09
- 摘要：As a novel environmentally friendly reinforcement method, the microbially induced carbonate precipitation (MICP) reinforcement technique has developed rapidly in recent years. The traditional MICP reinforcement method is limited by high reinforcement cost, poor environmental adaptability of exogenous mineralizing bacteria, and potential risks associated with the introduction of exogenous bacteria. The biostimulated MICP method using indigenous urease bacteria contained in soil can effectively reduce reinforcement cost and potential risks. In this paper, the biostimulated MICP method was used to reinforce the soil, and large-scale triaxial consolidation drained shear tests were carried out on specimens before and after treatment to compare and analyze the shear characteristics of the treated and untreated specimens. Moreover, the distribution and reinforcement mechanism of calcium carbonate in the biotreated soil specimen were also investigated. The results show that the biostimulated MICP treatment primarily generates rhombohedral-shaped calcium carbonate, which is deposited in the soil, leading to a significant increase in strength and stiffness, as well as a significant reduction in volumetric strain. The content of calcium carbonate in the soil specimen decreases with the increase of specimen depth, which leads to shear failure at the bottom of the specimen.关键词：microbially induced carbonate precipitation (MICP);soil reinforcement;biostimulation;large-scale triaxial test;shear characteristics;calcium carbonate distribution30|9|0更新时间：2026-06-09
- 摘要：Sandy loess has high sand content and a loose porous structure, and its mechanical properties are different from those of typical silty loess and sand. In order to study the effect of calcium source and curing method on the curing effect of microbially induced carbonate precipitation (MICP) technique in the treatment of sandy loess, small-scale tests were carried out by the soaking method and the perfusion method with three calcium sources (calcium chloride, calcium acetate and calcium lactate) respectively. The calcium carbonate content, calcium carbonate distribution uniformity and unconfined compressive strength (UCS) of the solidified samples were used as evaluation indexes for comparative analysis. The results show that the uniformity of the solidified samples is better when calcium acetate is used as the calcium source. The calcium carbonate content and UCS of the solidified samples are greater when calcium lactate is used as the calcium source in the early stage of treatment, but with the increase of treatment time, the strength of the solidified samples with calcium chloride as the calcium source is greater. Compared with the soaking method, the perfusion method can effectively improve the poor seepage of calcium lactate, and the curing effect is better than that of calcium chloride and calcium acetate when calcium lactate is used as the calcium source. The calcium carbonate distribution of the solidified sample by the perfusion method is more uniform and the strength is greater.关键词：microbially induced carbonate precipitation (MICP);calcium source;curing method;calcium carbonate content;sandy loess;unconfined compressive strength20|4|0更新时间：2026-06-09
- 摘要：Heavy metal contamination is one of the most prominent environmental issues worldwide, and heavy metal tailings are one of the main sources of such contamination. Biomineralization based on enzyme-induced carbonate precipitation (EICP), as a promising technique for the remediation of heavy metals, has many advantages such as high efficiency, greenness and environmental friendliness. In this study, soybean urease solution self-extracted from soybean powder was used to treat lead-zinc tailings. Heavy metal tolerance test, contaminated solution remediation test and lead-zinc tailings biomineralization test, as well as ICP, XRD and SEM-EDS analyses, were conducted to study the prevention of heavy metal contamination of lead-zinc tailings through soybean urease-based biomineralization. The test results showed that both Pb2+ and Zn2+ reduced the activity of soybean urease, and the effect of Pb2+ on urease activity was time-dependent, whereas the effect of Zn2+ was immediate. Soybean urease could effectively remove more than 99% of Pb2+ and Zn2+ in solution by forming protein complexes and inducing calcium carbonate precipitation. Meanwhile, the calcium carbonate precipitated by the soybean urease could encapsulate the tailings, reducing the amount of heavy metals leached by 70%.关键词：heavy metal contamination;enzyme-induced carbonate precipitation;lead-zinc tailings;soybean urease;contamination prevention21|3|0更新时间：2026-06-09
- 摘要：To enhance the durability of soybean-urease-induced calcium carbonate precipitation (SICP) in stabilizing aeolian sand, this study integrated SICP with xanthan gum (XG). By varying cementation solution concentration, spraying frequency, and spraying volume, together with three levels of XG concentration, the wind erosion mass loss, penetration resistance, and CaCO3 content of the treated specimens were quantitatively evaluated. The solidification behavior and reinforcement mechanism under the synergistic action of SICP and XG were analyzed, and the durability of the stabilized sand was further assessed through freeze-thaw and wet-dry cycle tests. The results show that the incorporation of XG substantially enhances both the wind erosion resistance and surface strength of SICP-treated samples. The peak penetration force of the SICP+XG specimens reached 68.4 N, representing increases of approximately 69% and 338% compared with pure SICP and pure XG (2 g/L), respectively. After undergoing nine freeze-thaw and wet-dry cycles, the wind erosion rate of the SICP+XG-treated samples remained at a low level of 0.03%-0.68%, indicating excellent erosion resistance. Scanning electron microscopy further revealed that XG forms a reticulated film on the sand grain surface, enhancing the binding efficiency of CaCO3 precipitation, while the deposited CaCO3 predominantly appears in the structurally stable calcite form.关键词：soybean-urease-induced calcium carbonate precipitation (SICP);aeolian sand;freeze-thaw cycles;wet-dry cycles;wind erosion prevention21|12|0更新时间：2026-06-09
- 摘要：To enhance the stability of tropical soil slopes, avoid the limitations of single reinforcement techniques, and develop green, low-carbon reinforcement techniques, this study investigates the feasibility of synergistically reinforcing low-liquid-limit clay using microbial induced calcium carbonate precipitation (MICP) and selected plants. Three typical tropical plants were selected, and carpet grass was identified as the most adaptable through simulations of tropical light, temperature, and post-MICP soil conditions, with its suitable cementation solution concentration range determined to be 0.2-0.6 mol/L. Direct shear, unconfined compression strength (UCS), and permeability tests were subsequently conducted, combined with SEM, EDS, and XRD microanalyses, to systematically evaluate the macroscopic properties and underlying mechanisms of the synergistic reinforcement. The results indicate that after the MICP-plant synergistic treatment, the soil’s cohesion, internal friction angle, and UCS increased by 145.9%, 100.4%, and 161.8%, respectively, compared to the untreated group, while the permeability coefficient decreased to 6.81×10-⁸ m/s, representing an improvement in anti-seepage performance by approximately two orders of magnitude. Microscopic analysis reveals that the calcium carbonate precipitated by MICP and the plant roots formed a “cementation-reinforcement” composite structure, which not only filled soil pores but also enhanced the anchorage effect at the root-soil interface. The synergistic effect of MICP and plants not only significantly enhanced the mechanical properties of tropical low-liquid-limit clay but also substantially improved its anti-seepage performance, effectively mitigating slope instability caused by rainfall infiltration and erosion under tropical storm conditions.关键词：microbially induced calcium carbonate precipitation(MICP);plant;permeability test;microstructural analysis;unconfined compressive strength (UCS)23|6|0更新时间：2026-06-09
- 摘要：Microbially induced calcium carbonate precipitation (MICP) technique shows significant potential for grouting and sealing micro-fractures in rock. However, its application is currently challenged by uneven precipitate distribution, where localized clogging can disrupt grouting continuity, compromise sealing reliability, and even introduce engineering safety risks. This study investigated the effects of grouting flow rate on permeability reduction and precipitate distribution characteristics during MICP-based fracture sealing using a self-designed fracture model apparatus. The experimental sequence followed analyzing the influence of flow rate on bacterial attachment efficiency, implementing mineralization grouting for fracture sealing, monitoring the permeability reduction process, and characterizing precipitate distribution through 3D scanning. The results indicate that an increase in grouting flow rate leads to a significant reduction in bacterial retention efficiency. Variations in grouting flow rate markedly affect the distribution patterns of precipitates in the fractures, and differences in the spatial distribution of precipitates further cause variations in the permeability reduction process. A flow velocity of 4.708 mm/s was identified as optimal, achieving both high grout utilization efficiency and effective sealing performance.关键词：microbially induced calcite precipitation (MICP);rock fracture sealing;grouting flow rate;precipitation distribution19|5|0更新时间：2026-06-09
- 摘要：The improvement of mechanical properties of granite residual soil is of great significance for engineering disaster prevention and control. In order to investigate the improvement effect of eco-friendly biopolymers on the mechanical properties of granite residual soil, xanthan gum (XG), guar gum (GG) and their composite gum (G-X) were used to modify granite residual soil, and the effects of biopolymer type, content, curing mode, and curing age on the improvement effect and its reinforcement mechanism were investigated through unconfined compression strength, triaxial shear strength and scanning electron microscopy tests. The results show that XG, GG, and G-X can improve the compressive strength of granite residual soil, and the compressive strength of improved soil under standard curing conditions increases continuously with polymer dosage but the increase slows down, while the compressive strength of improved soil under room temperature curing peaks, and the optimal dosage of polymer is about 1.0%-1.5%; The composite G-X improved soil has better compressive strength (up to more than twice that of untreated soil) and age stability, and the shear resistance is obviously improved (cohesion is about 2.4 times that of untreated soil), which combines the bonding effect of GG and the filling effect of XG, and presents a synergistic improvement effect.关键词：granite residual soil;biopolymer;xanthan gum (XG);guar gum (GG);mechanical properties;strengthening mechanism31|8|0更新时间：2026-06-09
- 摘要：The phenomenon of bioclogging in porous media is widely present in nature and engineering and is closely related to fields such as the environment, energy, and biomedical applications. In this work, we focus on the bioclogging process in porous media and investigate the effects of flow rate and pore size on the behavior of biofilm clusters and the evolution of permeability using a microfluidic chip-microscope-CMOS camera visualization experimental system. By integrating the microparticle image velocimetry technique, we achieved real-time dynamic observation of the flow field within porous media. Flow-visualization experimental results show that flow rate and pore size control the surface morphology and ultimate clogging efficiency of biofilms by influencing shear rates and nutrient exchange rates. It is shown that bioclogging in porous media presents two distinct clogging patterns, characterized by pattern Ⅰ with preferential flow paths and pattern Ⅱ without preferential flow paths. Pattern Ⅰ occurs under conditions of a smaller flow rate and larger pore size, where the fluid mainly flows concentrately in the preferential flow paths. The unevenness of the flow rate distribution is exacerbated over time, affecting the stability of clogging, and the permeability decline shows obvious intermittent fluctuations. Pattern Ⅱ occurs under conditions of a higher flow rate and smaller pore size, and the flow field distribution is relatively uniform with no obvious high-speed concentrated areas. In this pattern, the clogging effect is much more significant, with the permeability ratio being reduced by three orders of magnitude at the end of the experiments.关键词：porous media;bioclogging;permeability;preferential flow paths;biofilm morphology35|18|0更新时间：2026-06-09
- 摘要：The Dazu Thousand-handed and Thousand-eyed Avalokitesvara is widely regarded as a seminal example of Song Dynasty grotto art. Although the statue was restored in 2015, the preservation environment has not been effectively improved. It still suffers from issues such as gold foil delamination, cracking, and microbial erosion. Preliminary investigations by our research group into the microbial corrosion mechanisms on the gold foil indicated that the substrates generated from microbial metabolism could induce microbial colonization and alter the microenvironment of the gold foil surface. Nonetheless, the relationship between sealing materials and the microbiological colonization and corrosion processes on gold foil remains insufficiently studied. The present study established a Mucor fragilis-based culture system, incorporating raw lacquer, turpentine-modified lacquer, and tung oil-modified lacquer as sealing materials. These systems were combined with simulated corrosion experiments on gold foil surfaces to systematically evaluate the effects of different sealing materials on microbial physiological metabolism and the corrosion process. The results indicated that raw lacquer formed a stable biofilm structure with Mucor fragilis, providing both physical barrier and inhibition of organic acid secretion, thereby offering effective protection for the gold foil. Although the film morphology of turpentine-modified lacquer was relatively heterogeneous, its sustained mildly alkaline environment and low extracellular polymeric substances (EPS) concentration effectively suppressed microbial adhesion, suggesting a certain long-term protection potential. Tung oil-modified lacquer initially inhibited microbial growth through oxidative stress, but its protective effect diminished over time as fatty acid components were utilized as carbon sources.关键词：Thousand-handed and Thousand-eyed Avalokitesvara;gold foil;corrosion;Mucor fragilis;sealing materials20|4|0更新时间：2026-06-09
- 摘要：Windward lateral roots have been shown to play a significant role in the resistance of trees to overturning under typhoons.However, there is a paucity of research focusing on their behaviours under large displacements. Through physical model tests and finite element simulations, the force-displacement curves of root elements under large displacements were obtained. Subsequently, the bilinear softening assumption incorporating the Winkler foundation beam method was used to analyze the response of single windward lateral roots under horizontal loads. Effects of root diameter and length on the peak bending moment and rotational stiffness were investigated. The findings demonstrated that when the root length was less than the critical length, the peak bending moment increased with an increase in diameter and length, and exhibited heightened sensitivity to diameter. Additionally, the overall rotational stiffness and initial rotational stiffness both increased with the increase in diameter; however, the overall rotational stiffness decreased with the increase in length, while the initial rotational stiffness basically remained unchanged. When the root was longer than the critical length, the moment-rotation curve generally no longer changed, so the above indexes were unchanged. The critical length was fitted with root diameter and elastic modulus, which can satisfty the estimation of the critical length of thick roots in engineering.关键词：tree root;typhoons;lateral load;beam-on-a-nonlinear Winkler foundation;moment-rotation curve22|8|0更新时间：2026-06-09
Biogenic Construction
- 摘要：Uniaxial compression tests are conducted on dry and water-saturated red sandstone specimens containing a single hole. The objective of these experiments is to examine the characteristics of stress and deformation, crack propagation mechanisms, acoustic emission characteristics and energy evolution based on the TAW-2000 test equipment, camera system and PCI-2 acoustic emission detector. The results show that the mechanical parameters of water-saturated rock samples are significantly lower than those of dry rock samples while the brittleness drop coefficients significantly increase. The crack propagation process is comprised of four distinct stages: the initial deformation stage, crack initiation stage, crack stable propagation stage and crack unstable propagation stage. The initial fissures and secondary fissures of water-saturated rock samples are more numerous and longer, and significant stress drop appears when initial cracks generate and cracks propagate unsteadily. The ring counts of rock samples focus on the crack initiation and crack unstable propagation stages. In numerous water-saturated rock samples, AE signals are fewer than thase in dry rock samples. The AE signals during the crack initiation stage are more than those during the crack unstable propagation stage. Compared with dry rock samples, the external energy is easier to dissipate in the water-saturated rock samples and the energy storage rate is slower to reach the peak. Consequently, the stored elastic energy is reduced in the water-saturated rock sample, which is more conducive to reducing the intensity of energy release during rock failure.关键词：red sandstone;water-saturated state;hole;acoustic emission (AE);crack propagation;energy evolution23|4|0更新时间：2026-06-09
- 摘要：In the domain of high earth and rock dam engineering, the particle breakage and permeability characteristics of rockfill materials are important indicators that affect the physical and mechanical properties of dam materials. The quality control of rockfill materials post-vibratory crushing treatment is paramount for the construction of rockfill dams. A comprehensive study of the particle breakage and permeability characteristics of rockfill materials after vibratory compacting is, therefore, of the utmost importance. Indoor vibration tests were conducted on the scaled-down rockfill materials of the Yulongkashi Hydropower Station to investigate the particle breakage characteristics of rockfill materials under different vibration times. Laboratory constant-head penetration experiments were designed to measure the permeability coefficient of rockfill materials after vibratory compacting. The effect of varying vibration times on the change of permeability coefficient of the rockfill materials was analysed. A three-dimensional structural model was established based on the particle size distribution curve. Subsequently, a simulation of seepage was conducted on the model. Changes in the pore structure and permeability characteristics of rockfill materials under different vibration and compacting durations were compared. The results of indoor tests and model simulations were compared to validate the conclusions obtained from the indoor tests.Finally, some parameters affecting the permeability coefficient were subjected to fitting analysis, and the calculation formula of the permeability coefficient was obtained. The research results indicated that under the influence of vibration and compacting, the particle size distribution curve of the rockfill materials became smoother and the particle arrangement became more compact. After vibration compacting for four minutes, the porosity of the rockfill materials decreased from the initial value of 42% to 15%-17%, and the permeability coefficient decreased from 0.162 cm/s to 0.08-0.09 cm/s, and water flow within the pore structure slowed down. The established three-dimensional structural model well reflected this process.关键词：rockfill materials;particle breakage;vibration compaction;grading characteristics;permeability characteristics23|12|0更新时间：2026-06-09
- 摘要：In recent years, construction waste including recycled concrete, bricks and mortar has been widely used in subgrade construction. The bearing capacity and stability of the subgrade mainly depend on the shear strength of the subgrade filler. Construction waste filler particles are characterized by a wide grading range, low strength, complex composition, etc., and their shear characteristics under service load are significantly different from those of traditional sand and gravel fillers. The existing research results are reviewed from three aspects: shear characteristics of recycled construction waste fillers, shear characteristics of construction waste - fine grained soil mixed fillers, and interface shear characteristics between recycled construction waste fillers and geomaterials. Based on existing research, it is found that changes in particle morphology and distribution of different types of construction waste determine the type and mode of particle breakage, and particle breakage significantly affects the shear strength during the shear process. On the premise of meeting subgrade filling strength requirements, it is necessary to further explore the influence mechanism of particle breakage laws of different construction wastes on shear strength. In addition, although the shear strength of construction waste can be improved when mixed with different fine-grained soils, the research on the optimal mixing ratio and interaction mechanism of mixed soils is still insufficient. Research on the interfacial shear strength between construction waste and geotechnical materials mainly focuses on recycled fillers such as concrete and blocks. Due to the differences in material composition and properties of construction waste, it is necessary to conduct in-depth research on the interfacial shear mechanism of different construction waste fillers, so as to provide important theoretical support and technical reserves for the development of green and low-carbon transportation.关键词：construction waste;recycling filler;subgrade engineering;shear strength;particle breakage;fine-grained soil26|3|0更新时间：2026-06-09
- 摘要：The central and western regions of China are predominantly mountainous, and in the constructed and future railways, a substantial proportion of embankments must be constructed on inclined strata in mountainous areas. However,the extant research on the dynamics of reinforced embankments on inclined strata is relatively limited. Therefore, based on the finite element numerical software, this paper establishes a numerical model of geotechnical reinforced embankments under inclined bedrock conditions, and compares and verifies the computational results with the existing experimental results, and then conducts an in-depth study and analysis of the dynamic response characteristics of the reinforced track embankment based on this model, focusing on the effects of cyclic load amplitude and the number of layers of geogrid on the dynamic response of the reinforced embankment. The results show that the dynamic response of the vertical cyclic displacement amplitude and peak velocity of the embankment shows a significant spatial non-uniform distribution, and their extreme values appears directly below the loading centre. The high-value areas of lateral displacement of the embankment are distributed at the bottom of the left slope and the top of the right slope. With the change of each parameter, the lateral peak displacement at the top of the right slope of the embankment increases more significantly, and it becomes the area with the largest lateral displacement. The limiting effect of geogrids on the amplitude of lateral displacement of the reinforced embankment is significant. With the gradual increase in the number of geogrid layers, the overall lateral displacement magnitude of the embankment decreases, and the area where the lateral displacement magnitude occurs shrinks and gradually moves upward. At the position of each layer of geogrid, the curve of the lateral displacement magnitude of the embankment versus the depth of the embankment shows an obvious valley value, and the depth of the valley is consistent with the location of the geogrid arrangement. When four layers of geogrid are set, the lateral displacement amplitude between geogrids and the lateral displacement amplitude at the top of the geogrids are similar, which can effectively play the role of geogrids in limiting the lateral displacement of the soil body.关键词：inclined bedrock;geogrid;railway embankment;dynamic response;vertical displacement;numerical simulation20|5|0更新时间：2026-06-09
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Preparation and performance of ternary composite phase change concrete for building energy piles AI导读
摘要：In light of the defects and deficiencies in conventional phase change concrete, a novel composite phase change material (PCM) comprising decanoic acid-lauric acid-palmitic acid was incorporated into concrete to prepare phase change concrete. Therefore, the vacuum adsorption test was conducted, and the porous matrix material was encapsulated by two kinds of encapsulation method. The compressive strength test and thermal conductivity test were carried out on PCM concrete coarse aggregates and PCM concrete with different mix proportions under different encapsulation methods. The changes of different encapsulation methods under multiple phase change cycles were evaluated, and phase change cycle tests were conducted on the coarse aggregate of phase change concrete with two different encapsulation methodologies and the phase change concrete with different proportions. The results show that after 100 phase change cycles, the compressive strength loss rate of cement slurry encapsulation is 0.69%, 0.44% and 1.09% lower than that of epoxy resin + cement powder encapsulation when the content of phase change coarse aggregate is 10%, 20% and 30%, respectively. Therefore, the compressive strength loss rate of PCM encapsulated by the cement paste method can better meet the needs of pile concrete under long-term operation of energy piles. When the content of phase change coarse aggregate is 20%, the compressive strength, thermal conductivity and cyclic stability of phase change concrete are better, and the application range is wider.关键词：energy pile;phase change materials;phase change concrete;heat transfer performance;mechanical properties23|8|0更新时间：2026-06-09 - 摘要：Cables are the main force-transfer components of cable-stay bridges, and the safety and durability of the bridges will be threatened when the cables are seriously corroded. In this study, artificial accelerated corrosion, three-dimensional topography scanning and mechanical properties testing were carried out to explore the mechanism of the influence of additional zinc wire on corrosion expansion characteristics and mechanical properties degradation of the cables. Firstly, high-strength steel wire cable specimens with zinc wire and without zinc wire (control group) were prepared, and the artificial accelerated corrosion was carried out for 4, 8, and 12 weeks by spraying droplets through the annular openings set up in the sheaths to simulate the damage of the sheaths. Secondly, the Holon 3DX+ non-contact scanner was used to construct the point cloud model of the cable, and the influence of zinc wire on the corrosion expansion of high-strength steel wires was analyzed. Finally, the MTS testing machine was utilized to conduct static tensile tests on high-strength steel wires with varying degrees of corrosion. A correlation model between the cross section loss rate and the mechanical properties of the corroded high-strength steel wires was established, and the load-bearing performance of the cable was evaluated. The results show that after 4, 8, and 12 weeks of accelerated corrosion, the average values of the maximum section loss rate of the steel wire at the sheath opening of the zinc-added wires were reduced by 47.14%, 62.68%, and 38.70%, respectively, compared with those of the zinc-free wires; the average values of the ultimate strength of the steel wires at the sheath openings and the average values of the yield strength were increased compared with those of the cables without zinc wire by 0.17%, 6.12%, 5.55%, and -0.31%, 8.54%, and 6.24%, respectively; and the residual load carrying capacity of the cable was increased by 0.16%, 5.41%, and 4.83%, respectively.关键词：zinc wire protection;high strength steel wire cable;artificially accelerated corrosion;mechanical properties;corrosion morphology18|5|0更新时间：2026-06-09
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3D printed construction and mechanical properties analysis of unreinforced concrete arch structure AI导读
摘要：This paper presents a feasibility study on 3D printed lightweight concrete arch structures, examining three key aspects: design, construction, and load-bearing performance. Based on the characteristics of arch structures and 3D printing technology, a segment-assembly method was proposed to realize the accurate and fast assembly of arch structures. On this basis, five 3D printed lightweight arch structure specimens were constructed. The influence of three conditions, namely two-point concentrated load, three-point concentrated load, and uniformly distributed load, as well as the printing paths of “π”, “W”, and “M” cross-sections, was studied through experiments on the bearing performance of arch structures. Additionally, the mechanical behavior of 3D printed concrete arch structures with rise-span ratios of 1/4, 1/6, and 1/8 was analyzed using finite element calculations. The results show that the cooperative deformation ability of each segment and bearing capacity of the specimens under uniformly distributed load are the best, and the compressive advantage of 3D printed concrete materials can be fully utilized. The local collapse of the arch structure is easy to be caused by concentrated load, and the ultimate bearing capacity of arch specimens under two-point and three-point concentrated loads decreases by 30.2% and 14.2% respectively compared to that under uniformly distributed load. The specimen with “M” cross section printing path has the best force transfer mechanism, and the peak load per unit mass increases by 23.2% and 28.4%, respectively, compared with the specimens with “π” and “W” printing paths. Within the recommended range of rise-span ratios specified, the bearing capacity of 3D printed concrete arch structures gradually decreases as the rise-span ratio decreases. All five specimens investigated in this experiment demonstrate good load-bearing performance.关键词：3D printed concrete;prefabricated structure;arch structure;mechanical properties29|9|0更新时间：2026-06-09
Civil Engineering
- 摘要：Transition metal/carbon composite catalysts can effectively activate persulfate (PMS) to degrade organic pollutants. In the present study, a simple pyrolysis technique was used to effectively transform a composite hydrogel adsorbent loaded with Cu(Ⅱ) into a zerovalent copper/carbon composite catalyst (C-Cu), which efficiently activated PMS and rapidly degraded 2,4-dichlorophenol (2,4-DCP). Under conditions of pH= 5, a C-Cu dosage of 5 mg, and PMS concentration of 0.20 g/L, 2,4-DCP (0.1 mmol/L) was completely removed within 5 minutes, with a reaction kinetic constant as high as 3.434 2 min-1, which was 3 orders of magnitude higher than those of reported metal oxides. In compliance with the Integrated Wastewater Discharge Standard (GB 8978—1996) Grade I, C-Cu could stably operate for 81.3 hours in a dynamic column reactor. Under the coexistence conditions of pH=5-9, conventional inorganic salts, and natural organic matter, the degradation of 2,4-DCP in the C-Cu/PMS system was not significantly inhibited, demonstrating good environmental tolerance. Moreover, the C-Cu/PMS system showed superior removal performance for various chlorophenol pollutants. Quenching experiments of active species and EPR results consistently indicated that zerovalent copper acts as the active site for PMS activation, generating a large amount of 1O2 and ·O2-. LC-MS analysis results suggested that 2,4-DCP underwent processes such as dechlorination and ring-opening to achieve degradation and mineralization.关键词：hydrogel;persulfate;zero-valent copper;chlorophenol;catalysis23|5|0更新时间：2026-06-09
- 摘要：As water quality standards have improved and detection technology has advanced, the control of new pollutants has gradually become a research focus. The activation ability of divalent manganese toward peroxymonosulfate (PMS) was enhanced by the introduction of an electric field. The E-Mn2+-PMS synergistic process was developed for the removal of the refractory organic pollutant diclofenac (DCF) from water. Firstly, the effects of current density, PMS concentration, Mn2+ concentration, solution pH value and water matrix (NO3-、Cl-、HA) on the removal of DCF in water were discussed, respectively. The results indicated that the synergy index of the E-Mn2+-PMS process was 10.88 within 20 min of reaction, and its reaction rate constant was 19.250×10-2 min-1. The mineralization rate of DCF was 67.4% within 180 min under the experimental conditions: current density was 11.42 mA/cm2, PMS concentration was 1 mmol/L and Mn2+ concentration was 150 μmol/L. Acidic conditions facilitated the removal of DCF, and the optimal pH value was 3. NO3- had almost no effect on the removal of DCF, while Cl- and HA promoted the removal of DCF significantly. Subsequently, it was demonstrated by radical scavenger experiments, electron paramagnetic resonance (EPR) tests, and analysis of manganese intermediate valence substances. The non-radical pathways (Mn(Ⅲ) oxidation and 1O2 oxidation) dominated in the E-Mn2+-PMS process. In comparison with the Mn2+-PMS process, the amorphous MnO2 generated in situ under electric field conditions could quickly activate PMS to produce 1O2, achieving efficient removal of pollutants.关键词：electrochemistry;peroxymonosulfate;diclofenac;singlet oxygen;non-radical pathway23|2|0更新时间：2026-06-09
- 摘要：In the present study, attapulgite (AT), biochar (BC) and zeolite (ZO) were utilised as three distinct categories of exogenous porous passivators (EPP) in the construction of the anaerobic digestion system for chicken manure. The present study set out to analyse the morphological changes of organic nitrogen, organic phosphorus and copper (Cu), zinc (Zn) and heavy metal ions (HMs) in the digestion system by means of colourimetry and the BCR continuous extraction method. Furthermore, the passivation mechanism of Cu, Zn and the transformation and removal mechanism of nitrogen and phosphorus in the digestion system were explored by Infrared Spectroscopy (IR), X-ray diffraction (XRD) and three-dimensional fluorescence spectrum (EEM) characterization. The findings demonstrated that the incorporation of EPP could mitigate acid inhibition in the anaerobic digestion process. The addition of AT and ZO exhibited the most significant impact on the adsorption and transformation of total nitrogen (TN) and total ammonia nitrogen (TAN), which increased by 30.43% and 26.30% compared with the control group; The addition of ZO and AT had the most significant impact on total phosphorus (TP) and total phosphate (TPS), which increased by 9.33% and 17.74% compared with the control group; The contents of extractable (WA) and reducible (RD) copper and zinc in the three EPP groups were lower than those in the control group. The concentrations of WA and RD of Cu and Zn in the AT group were found to be 15.97% and 6.18% lower than those in the control group.关键词：livestock manure;anaerobic digestion;passivation of heavy metals;transformation of nitrogen and phosphorus;biogas fertilizer14|3|0更新时间：2026-06-09
Environmental Engineering
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