Volume 45, Issue 2 (2025)
Specially Invited Article
Review of Intelligent Construction Development of Highway Infrastructures and Its Prospects
ZHENG Jianlong, CHEN Mengjie, and LIU Chaochao
Date posted: 4-10-2025
DOI: https://doi.org/10.14048/j.issn.1671-2579.2025.02.001
With the rapid advancement of intelligent construction,intelligent development of highway infrastructures has emerged as a key research focus.This paper focused on the whole life cycle of intelligent construction of highway infrastructures and provided a comprehensive analysis of its current status,challenges,and future directions.The discussion was organized into five key areas:intelligent material design,intelligent structural design,intelligent construction management,intelligent inspection and monitoring,and intelligent maintenance management.In intelligent materials,the paper explored the application and recent advancements of the pavement material genome program.Regarding intelligent structures,the role of computer-aided design (CAD ) in pavement structural design was emphasized.For intelligent construction management,the importance and impact of intelligent monitoring systems throughout the pavement construction process were examined.In the area of inspection and monitoring intelligence,the current development and potential of embedded sensing units in pavements were discussed.Finally,in intelligent maintenance management,the paper evaluated the effectiveness and potential of ground-penetrating radar (GPR ) non-destructive testing technology in highway quality assessment.The findings reveal that although intelligent construction technologies have made progress in highway infrastructures,challenges remain,including incomplete technical systems,limited data integration,and high technical costs.The future of intelligent highway infrastructure construction should focus on standardization,technological innovation,and cross-domain collaboration,so as to establish an efficient,safe,and sustainable intelligent highway infrastructure system.
Subgrade Engineering
Study on Permanent Deformation of Subgrade High Liquid Limit Clay under Wetting Effects
WANG Xihui, ZHANG Laijun, and ZHENG Jiajia
Date posted: 4-10-2025
DOI: https://doi.org/10.14048/j.issn.1671-2579.2025.02.002
To investigate the mechanical properties of high liquid limit clay under different humidity and stress levels in hot and humid regions,high liquid limit clay in hot and humid regions was studied.Dynamic and static triaxial tests were carried out under different humidity and stress levels to reveal the stress-strain relationship and permanent deformation properties across different water contents and confining pressures.The results show that under low confining pressures of the subgrade,the stress-strain curves of the specimens exhibit either strain hardening or strain stabilization,and the failure strength of the specimens decreases with increasing water content and decreasing confining pressure.Based on the Konder hyperbolic model,the stress-strain relationship obtained from the static triaxial test was normalized,and a stress-strain equation for high liquid limit clay was established that simultaneously considered the effects of both water content and confining pressure.The permanent deformation of the specimen increased with the increase in the deviatoric stress,which was inversely correlated with the confining pressure,and the ability of the specimens to resist permanent deformation decreased under wetting effects.Based on the dynamic and static test results,a mechanical-empirical prediction model was proposed to predict the permanent deformation of subgrade soil by taking into account the shear effect,restraint effect,and damage due to wetting effects.The model featured high prediction accuracy and had been validated using experimental data from other scholars,proving its good applicability.
Influence of Deep Foundation Pit Excavation on Retaining Structure and Adjacent Tunnels
GAO Hongyun, XU Tianhan, WANG Zhihua, and LU Yao
Date posted: 4-10-2025
DOI: https://doi.org/10.14048/j.issn.1671-2579.2025.02.003
With the continuous advancement of urban construction,underground engineering has entered a period of rapid development.Foundation pit engineering will inevitably have an impact on the surrounding environment,especially on the existing structures.Based on the foundation pit engineering of Hongqiao Station of Nanjing Metro Line 5,this paper explored the influence of deep foundation pit excavation on its own retaining structure,surrounding ground surface,and adjacent existing municipal tunnels through on-site construction monitoring and numerical simulation.The results show that the excavation of the foundation pit results in a large settlement of the surrounding ground surface,and the maximum settlement position is about 0.35 the excavation depth from the foundation pit.The horizontal displacement of the diaphragm wall first increases and then decreases with the depth,reaching the peak value at the depth of 15–16 m.The maximum horizontal displacement at the end well is less than that at the standard section but does not exceed the limit value.When excavation proceeds to the pit bottom,the axial force of the third support is the largest,which is close to the location where the maximum deformation of the diaphragm wall occurs.The north side of the tunnel structure close to the foundation pit has a vertical uplift,and the horizontal direction has a small displacement towards the pit.
Experimental Study of Effect o f Organic Fertilizer Application on Swelling Soil f or Vetiver Planting
CHEN Dongjiong, WANG Guiya o, OUYANG Miao, and YANG Yanqi
Date posted: 4-10-2025
DOI: https://doi.org/10.14048/j.issn.1671-2579.2025.02.004
To promote the techni cal progress and popularization of ecological protection of swelling soil slopes,the characteristic that poor swelling soil is unfavorable to vegetation growth was considered,and a method of improving soil quality by using organic fertilizer was proposed,so as to better play the role of vetiver in protection of swelling soil slopes.The swelling soil from Guangxi Province was used as the research object,and compaction and swelling rate tests on swelling soil with different fertilizer contents were conducted to study the effect of organic fertilizer addition on the characteristics of swelling soil.Meanwhile,the partial factorial experimental design was used to study the effect of different organic fertilizer,slow-release fertilizer,and straw contents on the root system growth of vetiver and swelling of the root-soil complex.The results show that the maximum dry density of swelling soil decreases with the increase in organic fertilizer content,and the optimum moisture content and unloaded swelling rate increase with the increase in organic fertilizer content.The effect of slow-release fertilizer in promoting the early fertilization of vetiver is significant;straw can inhibit swelling,but it does not affect recent root system development.The improvement of root number and swelling rate is the most obvious when the organic fertilizer content is 5%,and the promotion effect of organic fertilizer on root system growth can compensate for its adverse effect on swelling soil.With the increase in organic fertilizer content,the improvement effect of root growth and swelling rate slows down.
Research on Identification of Subsurface Defects of Urban Roads and Collapse Risk Assessment
TIAN Gang, ZHANG Haijun, WANG Chengliang, DU Yanqing, and SHI Hai
Date posted: 4-10-2025
DOI: https://doi.org/10.14048/j.issn.1671-2579.2025.02.005
Based on ground-penetrating radar (GPR ) technology,this paper examined the formation characteristics,electrical properties,and morphological variations of common subsurface defects of urban roads.The paper summarized the radar spectrum characteristics of various subsurface defects,aiding in precise identification and providing a basis for subsequent assessment of road collapse risks.In addition,the paper integrated various factors,including subsurface defects,into the assessment of road collapse risk and established a “five-level ” assessment model.This led to an integrated research approach for detecting subsurface defects and assessing collapse risks.A road project in Beijing was used as a case study,and a trapezoidal membership function was applied to assign values to collapse-related indicators.Fuzzy calculations were employed to determine the collapse risk levels for subsurface defects 1#,2#,3#,and 4#,classified as Level Ⅱ (low risk ),Level Ⅲ (medium risk ),Level Ⅲ (medium risk ),and Level Ⅴ (high risk ),respectively.The results indicate that low-risk defect 1# requires enhanced routine inspections;medium-risk defects 2# and 3# necessitate regular inspections;high-risk defect 4# demands immediate grouting reinforcement or excavation and backfilling.
Pavement Structure and Materials
Coordinated Deformation of High-Modulus Asphalt Mixtures with Strain Gauges
LIU Zhaohui, GUO Zhihao, HUANG You, and LI Wenbo
Date posted: 4-10-2025
DOI: https://doi.org/10.14048/j.issn.1671-2579.2025.02.006
In order to improve the deformation coordination between the built-in strain sensors and asphalt mixtures,high-modulus fine aggregate asphalt mixture AC- 5 and conventional asphalt surface mixture AC- 13 were used as the base materials,and specimens were molded with built-in resistive strain sensors.Uniaxial compression,uniaxial tension,and four-point bending step-by-step loading tests were carried out in conjunction with digital image correlation (DIC).A finite element model verified by hypothesis testing was established to analyze the influence of high-modulus transition materials on deformation coordination under different working conditions such as burial depth of strain gauge,load size,and load type.The results show that under various types of loads,compared with that of the AC- 13 asphalt mixture,the measured strain data of the sensors in the AC-5 high-modulus asphalt mixture is closer to the measured data of DIC,and the measurement error is smaller and more stable.The specimens will have different measurement deviations when subjected to compression and tension,and the high-modulus asphalt mixture has some improvement in the deviation.In terms of the three influencing factors including burial depth of strain gage,load size,load size,and load type,the AC- 5 high-modulus asphalt mixture has different degrees of improvement on the coordinated deformation performance of the strain gage compared with the AC- 13 asphalt mixture.
Effect of Lightweight Aggregate with Water-Holding Capacity on Strength and Autogenous Shrinkage of Ultra-High Performance Concrete
FANG Chi, YANG Weihao, REN Kang, ZHANG Jinghang, LYU Yigang, HUANG Dunwen, and PENG Hui
Date posted: 4-10-2025
DOI: https://doi.org/10.14048/j.issn.1671-2579.2025.02.007
In response to the significant autog enous shrinkage issue of ultra-high performance concrete (UHPC ) under normal temperature curing,the influence of lightweight aggregates with water-holding capacity mixed with coarse aggregates on the compressive strength and autogenous shrinkage performance of UHPC was investigated.The mixing proportions of the two types of aggregates were optimized using the response surface method (RSM ).The results show that adequate amounts of basalt and volcanic rocks with water-holding capacity effectively reduce the shrinkage of UHPC.The rigid basalt restrains the shrinkage of the matrix,while volcanic rocks with water-holding capacity release moisture slowly,alleviating the autogenous drying effect and thus reducing shrinkage.However,an excessive amount of basalt and volcanic rocks leads to a decrease in the compressive strength of UHPC.This is because the coarse aggregates increase the transition zone between the matrix and coarse aggregates,resulting in fiber clustering,and the low strength of volcanic rocks makes it difficult to compensate for the degradation effect brought about by the transition zone.
Research on Mechanical Properties and Particle Crushing of Construction Solid Waste Concrete as Subgrade Filler
YU Nan, SONG Yang, BEI Bei, LI Xuejian, and QI Ziyi
Date posted: 4-10-2025
DOI: https://doi.org/10.14048/j.issn.1671-2579.2025.02.008
Construction solid waste is often used as subgrade filler,and its mechanical properties are greatly affected by moisture content and compaction degree.To explore the influence of these factors on the mechanical and particle crushing performance of construction solid waste,laboratory large-scale direct shear tests and particle screening tests were conducted.This study analyzed samples with varying moisture content and compaction degrees under a certain maximum dry density.The large-scale shear tests were carried out under three normal stress conditions:50 kPa,100 kPa,and 150 kPa,and the particle crushing characteristics of construction solid waste before and after shearing were analyzed.The results reveal notable changes in particle crushing form of the section before and after shearing of construction solid waste,which can be categorized into three types:rupture,abrasion,and grinding.The shear stress-shear displacement curve shows a “jumping” phenomenon.The cohesion of construction solid waste increases with the decrease in moisture content or the increase in compaction degree.Similarly, the internal friction angle rises with decreased moisture content or a higher degree of compaction.The overall screening statistics of construction solid waste show that the particle gradation curve moves upward,and the relative crushing rate of particles increases as moisture content decreases,or compaction degree increases.
Evaluation of Multi‑Source Aggregate Adhesion Performance Based on Rotary Bottle Test
WU Qian, TONG Daizhou, CHEN Songqiang, ZHANG Qunfeng, and REN Zhiqin
Date posted: 4-10-2025
DOI: https://doi.org/10.14048/j.issn.1671-2579.2025.02.009
The diversification of aggregate sources in pavement engineering has led to significant differences in aggregate properties,thereby affecting the adhesion performance between aggregates and asphalt.Accurately evaluating and distinguishing the adhesion performance between multi-source aggregates and asphalt are important prerequisites for ensuring the performance of asphalt pavement.A method for evaluating multi-source aggregates and modified asphalt based on rotary bottle tests and image processing was proposed.Rotary bottle tests were conducted on multi-source aggregates coated with modified asphalt,and the adhesion performance was quantitatively evaluated through the asphalt spalling rate obtained from image processing.Furthermore,the influence of factors such as immersion time and asphalt aging was analyzed.The evaluation results indicate that this method can clearly distinguish the differences in adhesion performance of multi-source aggregates,which has certain practical and engineering significance.
Preparation and Performance Study of Asphalt Modified by Polyphosphoric Acid/Desulfurized Crumb Rubber
YUAN Jianbo, YIN Chan, FENG Xinjun, and YU Fan
Date posted: 4-10-2025
DOI: https://doi.org/10.14048/j.issn.1671-2579.2025.02.010
To improve the comprehensive performance of desulfurized rubber asphalt,the asphalt was modified by using desulfurized crumb rubber and polyphosphoric acid.Based on the response surface method,the preparation parameters of the composite modified asphalt were optimized.In addition,four types of modified asphalt were prepared by using ordinary rubber,desulfurized rubber,composite polyphosphoric acid/ordinary rubber,and composite polyphosphoric acid/desulfurized crumb rubber.Their performance was compared.The results show that compared with ordinary rubber asphalt,the asphalt modified by desulfurized rubber has lower viscosity,significantly lower mixing and compaction temperatures,and more stable compatibility between rubber powder and asphalt in the system,which facilitates the preparation,storage,transportation,and construction process of rubber asphalt.In terms of road performance,the high-temperature deformation resistance of asphalt modified by polyphosphoric acid/desulfurized crumb rubber shows a level similar to that of ordinary rubber asphalt,and its creep ability is more excellent in low-temperature environments.Among the four types of modified asphalt,the asphalt modified by polyphosphoric acid/desulfurized crumb rubber has more obvious performance advantages and is suitable for promotion and application.
Research on Key Technologies for Reconstruction and Expansion of Loose Semi-Rigid Base Asphalt Concrete Pavement
XIAO Guancheng
Date posted: 4-10-2025
DOI: https://doi.org/10.14048/j.issn.1671-2579.2025.02.011
Some early-constructed semi-rigid base asphalt concrete pavements have severe looseness in the base layer,which makes it impractical to evaluate the fatigue life of the inorganic binder-stabilized layer for pavement reinforcement under these conditions.This kind of pavement widening project is affected by the condition of the existing pavement condition,raised elevation,traffic management,pavement regeneration,and other factors.Consequently,such projects pose significant challenges in reconstruction and expansion design.To address the key technical issues in reconstructing and expanding loose semi-rigid base asphalt concrete pavements,this article focused on the Shenzhen‒Shanwei West Expressway reconstruction and expansion project.Pavement overlay strengthening and widening techniques were studied through theoretical calculation and practical validation.The results show that by complying with relevant standards and considering pavement condition,the loose cement-stabilized base layer is treated as an unbound aggregate layer,and loose semi-rigid base asphalt pavement is simplified into a layered system comprising asphalt-bound material layer,an aggregate base layer,and the subgrade.A pavement structure reinforcement solution that meets regulatory standards is obtained.For scenarios involving different raised elevations of the existing pavement,factors such as split-width pavement scheme,construction feasibility,and traffic management are considered to obtain tailored pavement levelling solutions.For widening pavement,factors such as project traffic management,traffic distribution,and pavement regeneration need to be considered,and techniques such as step construction,body bolsters,and glass fiber grilles can be applied to enhance the quality of joints in loose base asphalt pavements.The first-stage project of the Shenzhen‒Shanwei West Expressway reconstruction and expansion was completed two years ago,and the pavement remains in good condition.The results confirm the effectiveness of the proposed pavement reconstruction and extension solution,offering insights and references for similar projects.
Road Performance of Fiber-Reinforced Semi-Flexible Pavement Materials
SUN Xuecong, WANG Hongchang, and LIU Song
Date posted: 4-10-2025
DOI: https://doi.org/10.14048/j.issn.1671-2579.2025.02.012
This paper aimed to investigate the reinforcement effects of basalt fiber,polyester fiber,and lignin fiber on semi-flexible pavement materials and study their applicability in different structural layers.The optimum bitumen-aggregate ratio under different fiber dosages was determined through the leakage test and dispersion test,and the optimum fiber dosage was determined through the Marshall test.The fiber reinforcement effect was evaluated through the Marshall test,rutting test,low-temperature bending test,freeze-thaw splitting test,and splitting fatigue test.A three-dimensional finite element model was established by using ABAQUS software to analyze the mechanical response of semi-flexible materials in different structural layers.The results show that basalt fiber,polyester fiber,and lignin fiber all improve the road performance of semi-flexible materials,with basalt fiber demonstrating a significant reinforcement effect in semi-flexible pavement materials.The semi-flexible materials have the best application effect in the upper and middle layers,which can improve the durability of pavement structures,effectively delay pavement fatigue damage,and enhance rut resistance,and they are particularly suitable for heavy-duty road sections and high-temperature environments.
Bridge Engineering & Tunnel Engineering
Study on Chloride Ion Diffusion Model in Crack Zones of Saturated Concrete Structure
PENG Jianxin, ZHOU Pengcheng, CHENG Xiaokang, and ZHOU Yadong
Date posted: 4-10-2025
DOI: https://doi.org/10.14048/j.issn.1671-2579.2025.02.013
In order to accurately characterize the b ehavior of cracks in accelerating chloride ion transport on both sides of the concrete,the concept of effective influence distance of cracks was proposed,and the crack pores were non-uniformly distributed according to the distance perpendicular to the crack surface in the modified equivalent medium model.The expression of chloride ion diffusion coefficient in crack zones of concrete was established based on the principle of flux conservation.Based on the existing experimental data,the applicability of the modified equivalent chloride ion diffusion model established in this paper was verified.Finally,the characteristics of non-uniform acceleration of chloride ion transport on both sides of concrete by cracks were discussed,and the influence of crack spacing and number on chloride ion transport was explored.It finds that the results obtained by the modified equivalent chloride ion diffusion model are in good agreement with the experimental data.The parametric studies show that with the increase in the distance perpendicular to the crack surface,the chloride ion content continues to decrease,and the chloride ion content on both sides is only 19% of that at the crack center point at the same depth of effective influence distance of cracks.The number of cracks has a certain influence on chloride ion diffusion,and the maximum increase in chloride ion content in multi-crack areas is 2% and 17% compared with that of single cracks.In addition,with the increase in the number of cracks,the diffusion capacity of chloride ions first increases rapidly and then flattens.The crack spacing has a significant effect on the multi-crack area of concrete,and with the increase in crack spacing,the overall chloride ion content in the multi-crack area decreases rapidly,and the decrease is the most obvious in the central area.
Application of Bridge Crack Recognition Algorithm Based on Image Connected Domain
HUANG Peng, FAN Wenzhe, HU Lingling, and WU Di
Date posted: 4-10-2025
DOI: https://doi.org/10.14048/j.issn.1671-2579.2025.02.014
To address the issues of low accuracy and poor practical performance in existing bridge crack recognition algorithms,this paper took the high-precision image of a bridge surface as the research object and proposed a crack recognition algorithm based on the characteristics of image connected domain and the calculation principle of the maximum inscribed circle (CIACM ).Firstly,traditional image processing algorithms such as graying,uniform light filtering,and edge detection were used to show the edge features of cracks.Then,based on the characteristics of the connected domain and the calculation principle of the maximum inscribed circle,the crack was identified,and the maximum width of the crack was screened.The experimental results show that the absolute error of the algorithm is not more than 0.02 mm;the average relative error is 2.47%,and the standard deviation is 1.52%.For fine cracks with widths < 0.2 mm,the average relative error and standard deviation are 4.71% and 1.54%,respectively,meeting bridge inspection precision requirements.The study demonstrates that the CIACM algorithm significantly improves crack recognition precision,particularly for fine cracks,and it provides reliable technical support for the automated assessment of bridge surface damage.
Seismic Reliability of Bridge Considering Material Deterioration during Whole Life Cycle
ZHU Kun, YAN Pengfei, TAN Hui, and LIU Guokun
Date posted: 4-10-2025
DOI: https://doi.org/10.14048/j.issn.1671-2579.2025.02.015
In order to study the influence of material property deterioration on the seismic performance of bridges during service,based on the principle of steel corrosion and Fick ’s second law,this paper analyzed the deterioration law of steel and concrete material properties and obtained the degradation law of rubber bearing properties over time.According to the theory of seismic vulnerability and risk,a method was established to calculate the seismic reliability of bridges.With a reinforced concrete box girder bridge in China as an example,the seismic vulnerability curve,risk curve,and seismic reliability during the whole life cycle of the bridge were calculated.The research shows that:① The bridge transcendence probability increases with the increase in peak acceleration aPGA under different damage conditions.The common deterioration of the pier column and bearing has the greatest influence on the seismic damage of the bridge,and the influence of pier column deterioration on the seismic damage of the bridge is greater than that of bearing deterioration；② A longer service life of the bridge means a greater bridge transcendence probability under the same seismic intensity,but the increasing range decreases with the increase in service time；③ With the increase in service time,the seismic reliability index of the bridge under various damage conditions decreases continuously.Among them,the seismic reliability of the bridge under the common deterioration of pier column and bearing decreases most obviously.Pier column deterioration alone has a greater influence on the seismic reliability of the bridge than that of bearing deterioration alone；④ A longer service time of the bridge indicates a greater seismic reliability difference between bridges with and without material deterioration considered.
Reasonable Design Scheme of Temporary Lateral Bracings for a Herringbone-Shaped Pylon without Crossbeams
WU Yuxian and LI Chuanxi
Date posted: 4-10-2025
DOI: https://doi.org/10.14048/j.issn.1671-2579.2025.02.016
The Xiangshan Bridge under construction is a semi-floating cable-stayed bridge with double pylons,double cable planes,and double-deck steel truss girders.The pylons are herringbone-shaped,with only corbels at the beam bottom and no crossbeams.The axis of the pylon limb is 9.9° to the plumb line,and the cantilever length is 165.8 m.The cantilever length of the inclined pylon limb is rare.In addition to ensuring the safety of pylon construction,reasonable design schemes of temporary lateral bracings should also facilitate the construction of pylons and temporary lateral bracings and save the investment of temporary lateral bracings.In view of the shortcomings of setting too many active lateral bracings (increasing unnecessary measures and costs ) caused by the traditional force safety principle,such as “the horizontal displacement of the inclined pylon limb does not exceed the allowable deviation of the axis,and the stress of the pylon limb does not exceed the standard”,a new simplified force safety principle that “the stress of the pylon limb does not exceed the standard” was adopted.Through the simulation calculation of each pylon construction stage by the finite element software Midas Civil,combined with the structural characteristics of the Xiangshan Bridge pylon and the hydrological and meteorological conditions of the bridge site,the design scheme of the temporary lateral bracings position,section size,active force size,and demolition sequence for the Xiangshan Bridge pylon was determined.The number of temporary lateral bracings in the obtained design scheme was small,and only one layer of active bracings was set.By using the obtained design scheme for lateral bracings,the construction of the pylon is smooth (it is about to cap ),and no cracks are generated.The axis deviation of the pylon is within the allowable range of the design.
Shear Behavior of Reinforced Concrete Beams Strengthened by CFRP under Different Interface Slip Models
JIANG Bing, WANG Fangli, and SUN Jianfeng
Date posted: 4-10-2025
DOI: https://doi.org/10.14048/j.issn.1671-2579.2025.02.017
To investigate the impact of different fiber reinforced polymer (FRP )-concrete interface bond-slip models on the shear performance of FRP-strengthened reinforced concrete beams,this study designed and cast five rectangular reinforced concrete beams.Four of these beams were reinforced with carbon fiber reinforced plastic (CFRP ) using four different methods:side strip spaced reinforcement,continuous strip reinforcement,U-shaped spaced reinforcement,and U-shaped continuous reinforcement.Field tests were conducted on the reinforced concrete beams.By utilizing Abaqus finite element analysis software,a finite element analysis model based on the interface debonding failure process was constructed by selecting three existing bond-slip models.The analysis results were subsequently compared with the experimental findings.The results indicate that the finite element simulations correlate well with the experimental observations regarding the failure process and ultimate load capacity of the reinforced beams.There is an increase in shear capacity ranging from 13.5% to 42.9%,while the finite element simulations demonstrate an increase between 5.5% and 47.7%.The shear and slip variation curves before and after debonding reveal that the FRP-concrete interface debonding occurs instantaneously.Following interface damage,the shear carried by the CFRP strips transfers to adjacent strips,further inducing interface damage that leads to strip delamination.Ultimately,the failure mode of the CFRP-reinforced concrete beams is characterized by progressive CFRP delamination,resulting in insufficient ultimate load capacity of the beams.Different bond-slip relationships result in variations in interface damage development,which subsequently influences the FRP strip delamination process and ultimately affects the overall FRP shear contribution.For identical reinforcement configurations,simulation results with varying bond-slip relationships indicate errors in CFRP shear contributions ranging from 0.1% to 15.9%.Among these,the Nakaba model demonstrates a more conservative CFRP shear contribution,while the Lu model generally provides the most accurate simulation results.
Sensitivity for Beam Height Parameter of Main Girder Fulcrum Section of Extradosed Cable-Stayed Bridge
TU Guangya, JIANG Xing, LIU Jing, and CHEN Linwei
Date posted: 4-10-2025
DOI: https://doi.org/10.14048/j.issn.1671-2579.2025.02.018
The beam height of the main girder fulcrum section is one of the important design parameters of the extradosed cable-stayed bridge.In order to study the influence of the beam height of the main girder fulcrum section on the mechanical performance of the main girder of the extradosed cable-stayed bridge,the parameter sensitivity analysis was carried out.The analysis kept the cable force,the number and location of longitudinal prestress of the main girder,and the beam height of the mid-span section unchanged and only changed the beam height of the main beam fulcrum section.The influence of the change on the bending moment,stress,and stiffness of the main girder under the bridge completion state,as well as the stress,bending moment,strength,and load-strength ratio of the main girder under the normal use limit state and the bearing capacity limit state was analyzed.The results show that the stress,internal force,strength,and load-strength ratio of the main girder of the extradosed cable-stayed bridge are highly sensitive to the beam height of the main girder fulcrum section.With the increase in the main girder fulcrum section,the negative bending moment of the corresponding main girder under the bridge completion state decreases;the bending strength of the main girder increases;the compressive stress of the upper edge of the main girder increases,and the compressive stress of the lower edge decreases.The change range of the compressive stress of the lower edge is greater than that of the upper edge,and the change range is greater as it is closer to the fulcrum section.The influence range is mainly from the side span L1/3 position (L1 is the side span length ) centered on the main pier to the middle span L2/4 position (L2 is the middle span length ).
Key Technology for Intelligent Construction of Ultra-High Concrete Cable Tower
MO Jun, ZHANG Wen, and YUAN Hang
Date posted: 4-10-2025
DOI: https://doi.org/10.14048/j.issn.1671-2579.2025.02.019
As the planning and deployment of cross-sea and river-crossing passages continue,prominent issues such as high labor demand and poor working conditions have become evident during the construction of large-span and ultra-high cable towers.To address these issues,this paper explored efficient construction methods for ultra-high cable towers based on the concepts of intelligent,industrialized,standardized,and assembled construction technology for cable towers.The research method combined qualitative analysis of reasonable construction organization,and integrated intelligent tower construction equipment for ultra-high cable towers,as well as industrialized forming and assembled construction technologies for tower column reinforcement was proposed.Through the application in the Lingdingyang Bridge along the Shenzhen‒Zhongshan Bridge project,the research results indicate that this key technology significantly enhances the level of intelligent construction technology for cable towers,effectively ensures operational safety,and further improves the quality of bridge tower construction.The paper verifies the feasibility and effectiveness of the proposed technology,providing important theoretical and practical guidance for the construction of ultra-high concrete cable towers.This has significant reference value for similar future projects and contributes to the innovative development of cable tower construction technology.
Date posted: 4-10-2025
DOI: https://doi.org/10.14048/j.issn.1671-2579.2025.02.020
This study investigate d the design sche me for reinforcing the loaded steel truss bridge using the section enlargement method through the Songpu Bridge rehabilitation project.It clarified the internal force calculation method and stress control principle for both original members and reinforced components and analyzed the influence of initial stresses in original members on the reinforcement effect.A combined theoretical and experimental approach was adopted,and an internal force distribution calculation method that considered the staged load-bearing process of reinforced components and original members was proposed,with the edge yield criterion of original members established as the stress control principle.Comparative analyses against the calculation methods specified in the Standard for Design of Strengthening Steel Structures (GB 51367 ‒2019 ) and bridge completion test data validated the rationality and effectiveness of the proposed reinforcement design scheme.The results demonstrate that the developed internal force distribution calculation method accurately calculates the internal force of members,while the edge yield criterion of original members ensures the reinforced steel bridge satisfies elastic stress requirements.Additionally,the study reveals that initial stress levels in original members significantly affect the reinforcement effect.It is recommended to implement partial unloading before reinforcement and control initial stress levels below 0.6.
Internal and External Prestress Reinforcement Technology for Prestressed Continuous Box Girder
SONG Chongyang, FU Xingran, GAO Hongbo, and HU Chengze
Date posted: 4-10-2025
DOI: https://doi.org/10.14048/j.issn.1671-2579.2025.02.021
A prestressed concrete cast-in-situ continuous box girder bridge faces transverse cracking of the bottom plate of the second span and the overall stiffness decline.To address this issue,this paper analyzed the causes of the damage.A finite element damage model considering the reduction of section stiffness and prestress loss was established,and the new prestress reinforcement degree was reasonably determined according to the principle of envelope design.An internal and external prestress reinforcement scheme was proposed,which included adding a long internal bundle to the outer web and adding a partial short external bundle to the bottom plate of the second span.Through construction monitoring and comparison of load tests before and after reinforcement,the precompression stress reserve was restored;the overall stiffness was improved,and the reinforcement effect was good.The internal and external prestress reinforcement technology has the advantages of effectively improving the stress condition and increasing the overall stiffness of the structure.It has wide adaptability and can be used as a reference for reinforcement of other similar projects.
Test and Correction of Effective Prestress in Bridges Based on X-Ray Diffraction
ZHANG Liang, ZHOU X udong, LI Yanbing, LI Yi, LI Pengfei, and HAN Xu
Date posted: 4-10-2025
DOI: https://doi.org/10.14048/j.issn.1671-2579.2025.02.022
To further enhance the servic e pe rformance of bridges and prolong structural service life,it is of critical importance to effectively detect the prestress of structural steel strands in bridges.Conventional detection methods have limitations in practical engineering applications,showing substantial variabilities in test results.The X-ray diffraction (XRD ) method,based on the microscopic scale analysis of metallic materials,derives macroscopic stress distribution through lattice spacing variations,demonstrating theoretical clarity and testing stability.This study pioneered the application of XRD in the field of effective bridge prestress detection.Comparative laboratory tension tests were conducted to investigate surface treatment process optimization and correct effective stress.The results demonstrate that the XRD method exhibits remarkable stability in prestress detection,with advantages including diverse application scenarios,low result variabilities,and high detection accuracy.Optimal surface treatment is achieved through grinding with hard abrasive wheels in combination with two-minute electrolysis in a 15 V lead-acid solution.Both linear and exponential correction formulas for effective stress grading are proposed.The research outcomes provide references for implementing XRD technology in bridge prestress detection.
Similar Materials for Tunnel Pre-Grouting Model Test in Fault Fracture Zone
ZHENG Kunlong, WANG Jianyun, LINGHU Yan, DING Yate, ZHANG Yujun, and WANG Zhifeng
Date posted: 4-10-2025
DOI: https://doi.org/10.14048/j.issn.1671-2579.2025.02.023
In order to obtain similar materials for tunnel model tests with wide matching and simple preparation methods,engineering materials such as gypsum,cement,river sand,and machine-made sand were selected,so as to meet the requirements of pre-grouting model tests for tunnel fault fracture zone that investigate the grouting effect of permeable crystalline slurry.Similar materials for surrounding rock,fracture zone,and tunnel lining were prepared through methods such as similarity constant calculation,material selection,and performance testing.The results show that the similarity constant was determined,such as Cl=50,Cγ=1,CE=50,and CQ=2 500.The experiment is conducted based on an optimized material ratio and preparation process.Similar materials with weight,compressive strength,and elastic modulus ranging from 16.65 to 17.58 kN/m3,0.21 to 0.93 MPa,and 29.72 to 113.74 MPa are prepared by using cement,river sand,and gypsum.When mRS∶mG∶mC∶mW=1∶0.15∶0.03∶0.04,the prepared materials meet the test requirements.Selecting machine-made sand with an average particle size of approximately 0.4 mm as a similar material for the fracture zone can effectively avoid particle size effects and reasonably simulate the characteristics of loose and broken rock and soil.Similar materials with an elastic modulus of 0.38‒0.62 GPa are prepared by using gypsum,barite powder,and cement.When mG∶mBP∶mC∶mW=1∶0.09∶0.05∶1.4,the prepared materials meet the test requirements,and the self-made polyvinyl chloride (PVC ) assembly mould is used for pouring.The results indicate that similar materials of surrounding rock,faults,and lining all meet the similarity relationship requirements of tunnel fault pre-grouting model tests.At the same time,by adjusting the ratio,the research results can provide more material choices for similar engineering simulations.
K-means Clustering and Control Analysis of Main Tunneling Parameters of Mud-Water Balanced Shields in Water-Rich Round Gravel Strata
LYU Yiye, PEI Lihua, LIN Dong, YANG Xingyu, and GUI Yue
Date posted: 4-10-2025
DOI: https://doi.org/10.14048/j.issn.1671-2579.2025.02.024
It is important to s et rea sonable tunneling parameters according to the ground conditions to reduce the deformation of existing tunnels,since the close crossing of new shield tunnels is likely to cause deformation in the adjacent existing tunnels.The K-means clustering algorithm was proposed to explore the correlation between tunneling parameters and surface settlement,and the optimal number of clusters was selected by using the sum of squared errors (ESSE) to measure the clustering quality.Through cluster analysis on the field monitoring data of the test section,three cluster centers were obtained.Finally,the optimal combination of tunneling parameters for mud-water balanced shield construction in water-rich round gravel strata was proposed.The optimal combination of tunneling parameters was verified by combining the parameter setting values of the actual underpass section and the deformation of the existing tunnel.The results show that ① the optimal combination of tunnelling parameters for mud-water balanced shield construction in water-rich round gravel strata is an average torque of 2 005 kN·m,a thrust of 14 380 kN,a tunnelling speed of 17.5 mm/min,and a difference in inlet and outlet mud flow of 57 m3/h;② after the optimal combination of tunnelling parameters is adopted,the vertical deformation of the existing tunnel near the underpass section is controlled within 0.58 mm,which achieves a relatively ideal deformation control effect.
Application Research on Steel Sleeve Combined with Working Shaft End Reinforcement for Shield Launching and Receiving Technology
YU Jingtao, ZHANG Feilei, ZHANG He, and XU Chao
Date posted: 4-10-2025
DOI: https://doi.org/10.14048/j.issn.1671-2579.2025.02.025
In view of the water and sand inrush risks faced by large-diameter slurry shield during launching and receiving in the water-rich silty fine sand stratum in the offshore area,the engineering practice of the double-lane shield tunnel at the bottom of the Karnaphuli River in Bangladesh was analyzed.The reasonable ranges of the tunnel portal chiseling thickness and the working shaft end reinforcement length were studied by theoretical calculation and numerical simulation.Finally,the reinforcement effect was evaluated through the analysis of shield tunneling parameters.The research results show that the reasonable range of longitudinal reinforcement of the end of the working shaft in the water-rich sand layer can be obtained by adding 2‒3 m to the length of the shield body.The comprehensive measure of sealed steel sleeve + triple tube high-pressure rotary churning reinforcement + well drainage + curtain for water sealing by grouting can effectively reduce the risk of water and sand inrush during the shield launching and receiving,and it has a high safety factor with good economy.The chiseling thickness of the diaphragm wall at the tunnel portal is 60 cm,which can ensure the safety of the tunnel portal and the construction progress.
Smart Road and Intelligent Transportation
Regulation Theory and Intelligent Incremental Launching Method for Simply Supported Closure of Cable-Stayed Bridges
ZHAN Lu, CHEN Changsong, LING Lihua, and HUANG Gen
Date posted: 4-10-2025
DOI: https://doi.org/10.14048/j.issn.1671-2579.2025.02.026
Main girder closure is the key process for cable-stayed bridges to achieve internal force and alignment goals.Focusing on the stress problem of main girder closure during the construction of cable-stayed bridges,this paper analyzed the mechanical characteristics of different construction methods of simply supported closure of the main girder based on the adaptive unstressed configuration control method of bridges and established an analysis method for calculating the manufacturing size of closure segment in simply supported closure method.Moreover,it put forward a new intelligent incremental launching method for simply supported closure with Jiayu Yangtze River Bridge as the background and analyzed the main girder alignment and structural stress results after closure.Finally,it verified the feasibility of the proposed new closure construction method.The results show that the measured alignment is basically consistent with the theoretical alignment,and the proposed closure method has high operability and can ensure high closure accuracy.
Construction of Disease Dataset Comprising 2D Images and 3D Morphologies of Highways
WANG Zijian, ZHANG Han, YAO Xinpeng, XIE Dongdong, and FAN Songhua
Date posted: 4-10-2025
DOI: https://doi.org/10.14048/j.issn.1671-2579.2025.02.027
In response to the lack of data samples for highway diseases both in China and abroad,this paper established a disease dataset that included 2D images and 3D morphologies of highways and clarified the principles of data collection,data processing methods,sample description,data quality control,and validation.The dataset contained 11 types of highway pavement diseases such as cracks,block cracks,longitudinal cracks,transverse cracks,subsidence,rutting,wave congestion,and potholes,in a total of 576 subdivided scenarios with different lanes,different light backgrounds,and different road structures.The dataset also comprised six types of traffic signs:warning signs,prohibition signs,directional signs,guide signs,tourist area signs,and road construction safety signs.This dataset could provide a large number of training samples for neural network models for defect detection on various highways and be used for small sample training of the YOLOV 7 model,verifying the effectiveness of the dataset.The results of the study show that establishing an image dataset based on highway scenarios can effectively deepen the understanding of highway diseases and pavement scenarios,provide an intelligent information-based solution to highway pavement disease detection,and lay a solid foundation for the training of relevant algorithmic models and the subsequent construction of the dataset.
Simulation Research on BRT Control Strategies for Intersections and Applicable Conditions
YANG Liu, LIANG Mia o, CAO Sen, and LI Wenfang
Date posted: 4-10-2025
DOI: https://doi.org/10.14048/j.issn.1671-2579.2025.02.028
The setting of bus rapid transit (BRT ) dedicated lanes at intersections and the priority of BRT fixed signals lead to a decrease in road utilization rate,an increase in CO2 emission,and the deceleration of vehicles at intersections during peak hours.To address these issues,four BRT control strategies for intersections were proposed by changing BRT dedicated lanes into intermittent ones and controlling BRT active signal priority.The study focused on intersections implementing median-road BRT dedicated lanes.Based on the simulation of urban mobility (SUMO ) software and its secondary development interface,this study succeeded in simulating four control strategies by using Python programming language.Through simulation experiments,the implementation effects of various strategies were compared when the total traffic volume Q at the intersections was in different values.The findings indicate that:① When Q is in the low traffic volume range of 0‒2 400 veh/h,the strategy of not opening the dedicated lane and not enabling signal priority has the best effect.② When Q is in the medium traffic volume range of 2 400‒4 800 veh/ h,the strategy of opening the dedicated lane but not enabling signal priority has the best effect.③ When Q is in the high traffic volume range of 4 800‒7 200 veh/h,the strategy of opening the dedicated lane and enabling signal priority has the best effect.The study clearly defines the applicable flow range for different BRT control strategies.
Foreign Highway
Deformation Control Measures for Precast Beam Yard on High Fill Roadbeds of Highway
XIE Xin, ZHAO Jun, SONG Zhanping, and GUO Wenguang
Date posted: 4-10-2025
DOI: https://doi.org/10.14048/j.issn.1671-2579.2025.02.029
In mountainous regions,high fill slopes and bridge structures are common due to topographical limitations,often leading to difficulties in transporting prefabricated bridge components.To address this situation,this paper proposed arranging a sunken precast beam yard on high fill roadbeds.The research analyzed the primary factors of roadbed settlement and deformation,applied multiple deformation control measures to manage the deformation of high fill roadbeds and the precast beam yard,and characterized their deformation through a three-dimensional numerical model analysis.The results show that replacing the lower soil layer with poor physical properties with a filler layer with better physical properties can effectively reduce the uneven settlement of the precast beam yard.After implementing settlement control measures,the overall settlement of the precast beam yard is approximately 20 mm,with uneven settlement limited to only 3 mm.The construction impact range of the precast beam yard on the underlying fill layer is similar to that of the beam yard area.
Overview and Prospect of Engineering Practice of Permanent Floating Bridge Structures
ZENG Zhuo, ZHENG Honggang, XIANG Sheng, and CHENG Bin
Date posted: 4-10-2025
DOI: https://doi.org/10.14048/j.issn.1671-2579.2025.02.030
As the bridge construction goes forward to the deep-water environments,the permanent floating bridge structures have attracted more and more attention from international scholars.The project cases of worldwide representative permanent floating bridges were presented.The structural systems of the built permanent floating bridges were summarized.The research and application advances regarding the mechanical features,the construction process,and the special configurations of the permanent floating bridges were introduced.Finally,from the perspectives of the engineering economy and environment applicability,the development prospect of permanent floating bridges was analyzed.The research shows that the permanent floating bridge structure has been applied in engineering around the world and has two types of structural systems,which are the continuous pontoon system and the discrete pontoon system.The permanent floating bridges adopted in deep-water environments have shown superior engineering economy.Based on further research and verifications,the permanent floating bridge structures can be applied in deep-water crossing projects.
