Structural Materials Commons^™

Deflection Basin Characteristics Of Distressed Roads Under Moving Load, Cai Yingchun, Xie Shenjian

Journal of China & Foreign Highway

The deflection basins of roads under moving load imply the distress information of subgrade and pavement.Therefore,how to use the information of deflection basins under moving load to rapidly test road distresses non-destructively has received much attention.In this paper,the finite element model of semi-rigid base asphalt pavement was established.By setting different types and degrees of finite element distress models,the continuous changes of surface deflection basins under moving load were analyzed.The results show that when the load moves to the distress area,the center deflection value of surface deflection basins in each distress model will become larger.When transverse cracks appear in the pavement …

Curing Mechanism And Influencing Factors Of Cement Mixing Piles Reinforcing Peat Soil, Feng Rongxian, Zhong Gaibing, Liu Liang, Liang Jianyuan, Gu Meixiang

Journal of China & Foreign Highway

The cement mixing pile is used to reinforce the deep peat soil foundation in Malaysia's east coast railway construction.The key in this project is to determine the cement mix proportion and additives.Considering the high organic matter content and strong environmental acidity of coastal peat soil,physical and mechanical tests of peat soil and laboratory uniaxial compression tests of cement soil under different mix proportions and influencing factors were conducted.Test results show that the mean compressive strength decreases by 0.35 MPa with the increase in cement-water from 0.5 to 0.9.Adding mineral powder gives a relatively poor curing effect while adding fly ash …

Safety Of Optimized Concrete Median Barrier Without Planting Soil, Zhong Chunyao, Ma Qing, Li Yangfan, Gong Shuai, Liu Siyuan, Yan Shuming

Journal of China & Foreign Highway

In order to study the safety of optimized concrete median barrier without planting soil,the technology combining computer simulation,sled test,and full-scale impact test of real vehicles was adopted for analysis and verification.In addition,a scheme was proposed to improve the anti-overturning ability of the barrier without planting soil by strengthening the supporting block,and the scheme of setting a 20 cm-high supporting block between the barrier walls was optimized.The safety of the barrier scheme was evaluated by taking the most unfavorable large truck as an example.The results show that the protection level of the optimized concrete median barrier without planting soil is SAm, …

Aided Design Method And Application Of Rutting Prevention And Maintenance In Asphalt Pavement Based On Digital Holographic 3d Detection, Wang Jingfei, Wang Wang, Xu Xinquan, Huang Zhijian, Ti Jing, Yao Yanru

Journal of China & Foreign Highway

As one of the common diseases of asphalt pavement,rutting has significant impacts on the service life and traffic safety of the pavement.Mild rutting in asphalt pavement during preventive maintenance can lead to increased use of maintenance materials due to rutting deformation.Accurately calculating the amount of materials needed to fill rutting in maintenance designs is of great significance for ensuring maintenance quality and efficiency.Based on the requirements of maintenance engineering,this paper analyzed the problems in maintenance designs that use traditional methods and the data they generate for rutting detection.A design method was proposed for rutting prevention and maintenance in asphalt pavement,assisted …

Polypropylene As Partial Fine Aggregate Substitute In Concrete, Samuel E. Royston, Chrisitan G. Achkar, Nicholas B. Tabarez

Architectural Engineering

The objective of this project is to discover a structurally effective method in repurposing recyclable plastic waste through its partial substitution for traditional fine aggregate in concrete.

Results obtained from analysis indicate a 25 percent compressive strength reduction with polypropylene at a 10 percent partial substitution for total sand content. This material successfully performed as an alternative, presenting a ductile mode of failure.

Three material alternatives - polypropylene, polyethylene, and rubber - were substituted for a percentage of sand. These materials underwent concrete cylinder crushing tests to determine their ultimate crushing strength, with the intent of identifying the most effective …

Effect Of Antioxidant Additives And Recycling Agents On Performance Of Asphalt Binders And Mixtures, Phase I, Nitish R. Bastola, Mahdieh Khedmati, Hamzeh Haghshenas, Jamilla Teixeira

Nebraska Department of Transportation: Research Reports

The use of reclaimed asphalt pavement (RAP) in asphalt mixtures has notably increased in recent times. Nevertheless, the inherent stiff and aged characteristics of RAP materials have consistently raised concerns regarding cracking performance. The use of recycling agents (RAs) has gained popularity in recent years since they can effectively modify the engineering properties of the aged asphalt binder. Besides that, the combination of RA with antioxidant (AO) additives has shown promise in enhancing the long-term performance of RAP mixtures. This research aims to investigate the effect of various RAs and one AO additive on performance of asphalt binders and high-RAP …

Quality Assurance And Quality Control For Reinforced Concrete Inspections, Calvin O. Walters Jr.

Publications and Research

Ensuring the safety and longevity of structures is paramount in concrete construction projects. Cases like the Big Dig ceiling collapse, which occurred on July 10, 2006, when a concrete ceiling panel measuring 20' x 40' and debris weighing 26 short tons (52,000 lb) fell within Boston's Fort Point Channel Tunnel, underscore this importance (Wald, M. L., 2007). Quality Assurance (QA) and Quality Control (QC) are crucial in mitigating such risks. QA ensures that materials and methods meet predetermined performance, design, and reliability standards specified in contracts and customer arrangements. On the other hand, QC is a strategic process businesses use …

Reasonable Construction Method For Grade Ⅳ Surrounding Rock In Single‑Hole Four‑Lane Super‑Span Highway Tunnel, Li Heyin, Gao Jingming, Li Yanfeng, Xun Wenjie, Dong Fangfang, Zhang Jiangang

Journal of China & Foreign Highway

In order to study the reasonable constr uction method of super-span highway tunnels，the Xinghuacun No.1 tunnel included in the reconstruction and expansion project of the Xiaocaohu –Urumqi section of the Lianyungang –Khorgos Expressway in Xinjiang was studied.The numerical simulation method was used to analyze the deformation and stress of the supporting structure of the Grade tisurrounding rock in the super-span highway tunnel constructed by the center diaphragm （CD） method，the upper-bench CD method，and the three-bench and seven-step excavation method.Under the premise that the deformation and the stress of the supporting structure met the design requirements，the advantages and disadvantages of each construction …

Intelligent Bridge Lifecycl E Maintenance System Based On Long‑Term Inspection, Ye Zhiwei, Zhang Jiaxin, Tan Haishan, Fan Lei, He Wen, Dong You, Wu Wanglin

Journal of China & Foreign Highway

The current bridge maintenance sy stem in China primarily relies on bridge inspection data to prioritize the state of bridges and allocate a limited budget accordingly.This strategy focuses on repairing bridges with low performance，concentrating on restorative maintenance but ignoring preventive maintenance.In view of the total lifecycle cost，the repair-oriented method may require a lower initial investment but leads to significant resource consumption in the mid to late stages.Based on existing highway bridge maintenance systems，an intelligent maintenance system relying on Chinese standards and bridge inspection data and combining repair and prevention was developed.The system model mainly consisted of two modules：the bridge performance …

Mechanical And Deformation Characteristics Of Piles In Coastal Soft Soil Areas Considering Softening Effect, Wang Fei, Yan Yu, Jiao Lidong, Shen Fengqi, Chen Lu, Liu Jianhua

Journal of China & Foreign Highway

In order to discuss the mechanical and deformation behavior of piles in coastal soft soil areas under horizontal load，the corresponding simplified mechanical model was established according to the loading characteristics of piles in coastal soft soil areas.Secondly，the softening effect of coastal soft soil was considered to modify the existing p-y curve model.On this basis，the differential equation of pile deflection in coastal soft soil areas was derived，and its internal force and displacement were solved by the transfer matrix method.A nonlinear calculation method of piles in coastal soft soil areas considering the softening effect was obtained.Finally，the influence of softening parameters，pile diameter，and elastic …

Experimental Study On Fracture Performance Of Emulsified Asphalt Cold Recycled Mixture, Chu Chenfeng, Deng Jun, Zhou Chen, Wang Zi ’Ang, Kuang Ao, Liu Hongfu

Journal of China & Foreign Highway

Cracking in emulsified asphalt cold recycled pavements is one of the main constraints on their large-scale application in road engineering.To study the fracture performance indicators of cold recycled asphalt mixture and the improvement measures of crack resistance performance，this study investigated three types of mixtures：ordinary emulsified asphalt，basalt fiber，and styrene-butadiene rubber （SBR） modified emulsified asphalt.This study conducted a four-point bending strength test on notched beams，and acoustic emission tests of the beam with prefabricated cracks were carried out to evaluate the fracture performance of three different emulsified asphalt cold recycled mixtures in road engineering.The evaluation criteria included strain energy release rate，stress intensity factor，energy …

Experiment On Strength And Deformation Characteristics Of Marine Silt Cement Soil And Their Relationship, Deng Wu, Liu Weizheng, Chen Tie, Ge Mengyuan

Journal of China & Foreign Highway

In order to study the compre ssive，flexural，and shear strength and deformation characteristics of marine silt cement soil，a series of laboratory mix ratio tests were carried out，so as to test the changes in unconfined compressive strength fcu，flexural strength ff，normalized shear strength τqg，normalized principal stress difference （σ1‒σ3）/σ3，and compression modulus Es under different dosage of curing agents，curing ages，and cement-to-lime ratios.In addition，the correlation between different parameters was investigated.The results show that the performance of the improved samples with cement and lime is 2%‒17% higher than that with cement alone under the same dosage.The strength of cement soil is proportional to the dosage and age …

Study On Compression Characteristics Of Solidified Mud‑Sand Mixed Fillers Considering Particle Breakage, Han Chao, Yu Yuezhong, Bai Bin, Xu Zhihao, Zhang Xianmeng, Liu Yinying, Kong Shuoying

Journal of China & Foreign Highway

The mixed filler of solidified mud and sand provides an ideal solution for the resourceful disposal of wasted engineering mud，and the compression characteristics of filling engineering are closely related to the strength characteristics and particle breakage characteristics of mixed fillers.This study conducted large size compression tests on mixed fillers with different particle gradations and established a discrete element method （DEM） model that incorporated particle breakage for the side-limited compression tests of solidified mud-sand mixed fillers.The changes in the compression modulus of the mixed fillers and the amount of solidified soil particle breakage during compaction were investigated.The study placed a special …

Mechanical Performance Of Uhpc Building Envelope Based On Topological Optimization And Modular Composition, Zhou Zhixuan, Jiang Youbao, Liu Jun, Xiang Yi, Zhou Hao

Journal of China & Foreign Highway

To ensure a safe，aesthetic，and lightweight building envelope，an ultra-high performance concrete （UHPC） building envelope and its node connection mode were proposed based on topological optimization and modular composition.Firstly，the UHPC building envelope was optimized by using the method of minimizing structural compliance subjected to given material volume constraints，and the mechanical performance before and after optimization was compared.The modular design was adopted，and the optimization result of the most unfavorable stress area in the model was taken as the basic configuration unit.Then，UHPC tenon and mortise nodes were proposed，which could be simply assembled into modules.By considering the weak mechanical performance of nodes，the finite element analysis …

Key Techniques For Demolition Of Multi‑Span Continuous Arch Bridge With Concrete‑Filled Steel Tubes, Wan Chengf U, Zeng Wenli

Journal of China & Foreign Highway

Taking the demolition project of Jianhu Bridge as the research background，the demolition of arch bridges with concrete-filled steel tubes under complex conditions was studied.First，the current bridge demolition methods and application status were introduced，and three bridge demolition schemes were put forward according to the difficulties of the bridge demolition.The appropriate demolition scheme for the bridge was selected after comparison，and the sequence of arch bridge demolition was explained.Then，the stress characteristics of the bridge at each construction stage were analyzed，and the theoretical and measured displacement and stress at the most unfavorable stage during demolition were compared.Finally，the influence of material strength and temperature on …

Parameter Sensitivity Analysis Of Single‑Tower Cable‑Stayed Bridge With Mixed Beam, Chen Kongliang, Ye Jianxin, Xu Yufeng, Huang Zhuobin, Guo Fengtao

Journal of China & Foreign Highway

To improve the efficiency of the review simulation model of the bridge monitoring unit and study the influence of different parameters of the single-tower mixed beam cable-stayed bridge on the bridge ’s completed state in the construction process，this paper，taking the cable-stayed bridge of Tongji Road in Foshan with a span of （200+68+46） m as the engineering background，adopted the single control variable method and response surface-Monte Carlo method for sensitivity analysis.Taking the main beam alignment，main tower alignment，main beam stress，and the variation of cable-stayed bridge force as control objectives，this paper studied the influence of the variation of main beam weight，initial tensile force，and …

Design And Installation Technology Of Hanging Basket For Long‑Span Concrete Girder Cable‑Stayed Bridge, Zeng Xianliu, Pang Jianguo, Chen Cheng

Journal of China & Foreign Highway

The main bridge of Zhungeer Yellow River Super Major Bridge is a （160+440+160） m double tower double cable plane full floating system concrete grider cable-stayed bridge.The main beam is a 28.4m wide double box prestressed concrete structure.It was constructed by cantilever pouring with a front fulcrum hanging basket.The maximum weight of the cantilever pouring section is 5 800 kN.To ensure the integral rigidity of the hanging basket，the hanging basket bearing platform adopted the steel box girder structure.The long and large components were connected by high-strength bolts made in sections to facilitate the transportation and installation of the hanging basket.The hanging …

Research On Road Performance Of Carbonaceous Shale Subgrade Filler, Zhang Mengjin, Huang Yafei, Wu Qian, Mao Xuesong, Zhang Jianxun, Chen Xinyi, Wang Yueyue

Journal of China & Foreign Highway

The application of carbonaceous shale for subgrade filling not only alleviates the shortage of subgrade filler in carbonaceous shale distribution areas but also meets the strategic requirements of “resource conservation and saving ” and “green development ” for infrastructure construction in China.However，such rocks are weak and susceptible to weathering and disintegration，and they exhibit significant strength deterioration when exposed to water.To fully apply them，their performance must be comprehensively understood.In this paper，the basic properties of the carbonaceous shale were studied，and filler gradation was designed.The tests on compaction characteristics of the filler and particle crushing characteristics after compaction，RCBR （California bearing ratio ） variation …

Mesoscopic Numerical Simulation Of Concrete Cracking Caused By Nonuniform Corrosion Of Strands, Zeng Tianbao, Chen Hong, Huang Xiaoqi, Tu Ronghui, Dai Lizhao

Journal of China & Foreign Highway

The non-uniform corrosion of spinning strands will induce concrete cracking.A non-uniform expansion model of corrosion products of strands was established，and a mesoscopic numerical model of concrete cracking caused by non-uniform corrosion of strands was built.Concrete was considered as a three-phase composite material composed of mortar matrix，aggregate，and interface layer.The concrete cracking behavior caused by the non-uniform corrosion of strands was simulated by embedding cohesive elements.The rationality of the proposed model was verified by existing experimental data，and the influence of protective layer thickness and aggregate content of concrete on the width of corrosion-induced cracks was discussed.The results show that the proposed non-uniform …

Research And Field Test On Ultra‑Thin Wearing Course Based On Balanced Design Concept, Gu Jianjun, Li Xia, Li Atan, Sun Qiang, Li Jie, Jiang Zhaowei

Journal of China & Foreign Highway

To address the application of an ultra-thin wearing course in expressway asphalt pavement maintenance engineering，the ultra-thin wearing course system based on the balance design concept was systematically studied.In this paper，the action mechanism and application characteristics of modifiers were analyzed，and the proportion design test of the ultra-thin wearing course was designed based on the balance design method.Finally，according to the proportion design test，the optimal proportion of the ultra-thin wearing course material was selected for test road paving.Research shows that the direct-cast high viscosity modifier is convenient for transportation and storage，improves the elastic recovery of asphalt mixtures and reduces permanent deformation.Under the condition …