Open Access. Powered by Scholars. Published by Universities.®

Civil and Environmental Engineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 1021 - 1050 of 4617

Full-Text Articles in Civil and Environmental Engineering

The Association Between Drought Exposure And Respiratory-Related Mortality In The United States From 2000 To 2018, Yeongjin Gwon, Yuanyuan Ji, Jesse E. Bell, Azar M. Abadi, Jesse D. Berman, Austin Rau, Ronald D. Leeper, Jared Rennie Jun 2023

The Association Between Drought Exposure And Respiratory-Related Mortality In The United States From 2000 To 2018, Yeongjin Gwon, Yuanyuan Ji, Jesse E. Bell, Azar M. Abadi, Jesse D. Berman, Austin Rau, Ronald D. Leeper, Jared Rennie

Daugherty Water for Food Global Institute: Faculty Publications

Climate change has brought increasing attention to the assessment of health risks associated with climate and extreme events. Drought is a complex climate phenomenon that has been increasing in frequency and severity both locally and globally due to climate change. However, the health risks of drought are often overlooked, especially in places such as the United States, as the pathways to health impacts are complex and indirect. This study aims to conduct a comprehensive assessment of the effects of monthly drought exposure on respiratory mortality for NOAA climate regions in the United States from 2000 to 2018. A two-stage model …


A High-Speed Portable Ground Heat Exchanger Model For Use In Various Energy Simulation Software, Ryan Davies, Matt Mitchell, Edwin Lee Jun 2023

A High-Speed Portable Ground Heat Exchanger Model For Use In Various Energy Simulation Software, Ryan Davies, Matt Mitchell, Edwin Lee

Macalester Journal of Physics and Astronomy

A portable component model (PCM) of a ground source heat pump system was developed and used as a test case in the creating of a PCM development framework. By developing this framework, new building energy simulation models will be able to be easily integrated into existing simulation software such as EnergyPlus and the Modelica Buildings Library. Our model uses a time responsive g-function and numerical methods to simulate ground source heat pumps for single time steps as well as long time scales. We validated our model against GHESim and GLHEPro and found that our model agrees with these two standards …


Assessing Boil Water Notices As Health-Risk Communication: Risk Perceptions, Efficacy, And Compliance During Winter Storm Uri, Ashleigh M. Day, Sydney O'Shay, Khairul Islam, Matthew W. Seeger, Shawn P. Mcelmurry Jun 2023

Assessing Boil Water Notices As Health-Risk Communication: Risk Perceptions, Efficacy, And Compliance During Winter Storm Uri, Ashleigh M. Day, Sydney O'Shay, Khairul Islam, Matthew W. Seeger, Shawn P. Mcelmurry

Open Data at Wayne State

Winter Storm Uri was an extreme disaster that impacted much of the United States during February of 2021. Texas and Oklahoma were generally not prepared for such an event and experienced massive power grid failures. This led to cascading risks including water system disruptions and many boil water notices (BWNs). The breakdown of some communication channels and the inability to enact protective actions due to power outages, as well as travel limitations on public roads, complicated both dissemination and implementation. Under these conditions, a non-representative, cross-sectional, survey was collected to assess individuals experience BWNs and how perceived efficacy impacts compliance. …


Modeling Potential Damages Of Hurricanes At The Facility Scale: A Case Study Of Eglin Air Force Base, Alexander J. Baldwin, Christopher M. Chini, Steven J. Schuldt, Justin D. Delorit Jun 2023

Modeling Potential Damages Of Hurricanes At The Facility Scale: A Case Study Of Eglin Air Force Base, Alexander J. Baldwin, Christopher M. Chini, Steven J. Schuldt, Justin D. Delorit

Faculty Publications

Tropical cyclones have intensified and are expected to strengthen throughout the 21st century due to climate change impacts. Storm intensification poses a serious threat to coastal municipalities and infrastructure that are not designed to withstand future wind and storm surge potential. Coupled modeling software has been widely used to replicate extreme weather events and simulate climate change effects to understand the magnitude of vulnerability coastal regions face. However, these studies are often conducted at too coarse resolutions to provide decision makers with actionable information for facility-level adaptation. This study addresses this limitation using a coupled modeling approach by simulating climate-intensified …


Exploring The Potential Of Pavegen’S Kinetic Energy Generating Floor For Sustainable Energy Solutions: A Proposal For Cal Poly Slo, Brandon J. Cuneo Jun 2023

Exploring The Potential Of Pavegen’S Kinetic Energy Generating Floor For Sustainable Energy Solutions: A Proposal For Cal Poly Slo, Brandon J. Cuneo

Construction Management

This paper proposes the installation of Pavegen's kinetic energy generating floors at Cal Poly’s campus as a sustainable energy solution. Pavegen has developed a pioneering technology that converts footsteps into clean and renewable energy. The versatility of these floors is demonstrated through successful implementations in various settings, such as transportation hubs and public spaces, generating power from foot traffic. Collaborations with Schneider Electric, installation at Dupont Circle, and integration at Heathrow Airport showcase the potential for sustainable urban infrastructure. This paper outlines research conducted on Pavegen and similar solutions, including communication with company representatives and examining proposed installation locations at …


Attainable And Sustainable Home Building Solutions, Katrina Matthews Jun 2023

Attainable And Sustainable Home Building Solutions, Katrina Matthews

Construction Management

Sustainability has fortunately been a recent concern in the construction industry as climate change continues to impose potentially insurmountable threats to the global environment. Although many new methods have been adopted in efforts to lessen the adverse environmental effects of construction-related activities, as a society, we still have much room for growth as the built environment accounts for almost 50% of global emissions. Many changes and standards must be adopted to make these solutions efficiently beneficial. To set industry standards, we must start with the most basic form of construction- residential building. This report covers two attainable framing solutions for …


Drinking Water Contaminants: Lead, Bruce I. Dvorak, Becky M. Schuerman Jun 2023

Drinking Water Contaminants: Lead, Bruce I. Dvorak, Becky M. Schuerman

Department of Civil and Environmental Engineering: Faculty Publications

Any lead exposure, even low levels, can be a serious health concern, especially for infants, children, and developing fetuses. This NebGuide discusses how to safely manage lead in a domestic water supply (or often referred to as a private well). This NebGuide includes discussion related to topics such as lead services lines and changes in public water supply regulations related to lead in drinking water.


Ocapo: Occupancy-Aware, Pdc Control For Open-Plan, Shared Workspaces, Anaradha Ravi, Archan Misra Jun 2023

Ocapo: Occupancy-Aware, Pdc Control For Open-Plan, Shared Workspaces, Anaradha Ravi, Archan Misra

Research Collection School Of Computing and Information Systems

Passive Displacement Cooling (PDC) has gained popularity as a means of significantly reducing building energy consumption overheads, especially in tropical climates. PDC eliminates the use of mechanical fans, instead using chilled-water heat exchangers to perform convective cooling. In this paper, we evaluate the impact of different parameters affecting occupant comfort in a 1000m2 open-floor area (consisting of multiple zones) of a ZEB (Zero Energy Building) deployed with PDC units and tackle the problem of setting the temperature setpoint of the PDC units to assure occupant thermal comfort. We tackle two key practical challenges: (a) the zone-level (i.e., occupant-experienced) temperature differs …


Optimal Domain-Partitioning Algorithm For Real-Life Transportation Networks And Finite Element Meshes, Jimesh Bhagatji, Sharanabasaweshwara Asundi, Eric Thompson, Duc T. Nguyen Jun 2023

Optimal Domain-Partitioning Algorithm For Real-Life Transportation Networks And Finite Element Meshes, Jimesh Bhagatji, Sharanabasaweshwara Asundi, Eric Thompson, Duc T. Nguyen

Civil & Environmental Engineering Faculty Publications

For large-scale engineering problems, it has been generally accepted that domain-partitioning algorithms are highly desirable for general-purpose finite element analysis (FEA). This paper presents a heuristic numerical algorithm that can efficiently partition any transportation network (or any finite element mesh) into a specified number of subdomains (usually depending on the number of parallel processors available on a computer), which will result in “minimising the total number of system BOUNDARY nodes” (as a primary criterion) and achieve “balancing work loads” amongst the subdomains (as a secondary criterion). The proposed seven-step heuristic algorithm (with enhancement features) is based on engineering common sense …


Understanding The Flow Dynamics Of The Pearl River, Ms, Through Hydrodynamic Modeling, Nahruma Mehzabeen Pieu Jun 2023

Understanding The Flow Dynamics Of The Pearl River, Ms, Through Hydrodynamic Modeling, Nahruma Mehzabeen Pieu

Master's Theses

The Pearl River brings fresh water and nutrients into Lake Borgne regulating conditions for oyster growth in estuarine waters. However, there are no flow measurement stations installed on East Pearl or West Pearl either at the river outlets or after the upstream bifurcation of the Pearl. This study aims to model the Lower Pearl River to understand the flow dynamics in the major branches, and to determine the final outflow distribution into the Mississippi Sound, aiming to improve river forcing for ocean models studying estuarine dynamics of the Mississippi Sound.

Synthetic meandering bathymetry with updated banks is developed and applied …


Fate And Transport Of Per- And Polyfluoroalkyl Substances (Pfas) At Aqueous Film Forming Foam (Afff) Discharge Sites: A Review, Jeffery T. Mcgarr, Eric G. Mbonimpa, Drew C. Mcavoy, Mohamad R. Soltanian May 2023

Fate And Transport Of Per- And Polyfluoroalkyl Substances (Pfas) At Aqueous Film Forming Foam (Afff) Discharge Sites: A Review, Jeffery T. Mcgarr, Eric G. Mbonimpa, Drew C. Mcavoy, Mohamad R. Soltanian

Faculty Publications

Per- and polyfluorinated alkyl substances (PFAS) are an environmentally persistent group of chemicals that can pose an imminent threat to human health through groundwater and surface water contamination. In this review, we evaluate the subsurface behavior of a variety of PFAS chemicals with a focus on aqueous film forming foam (AFFF) discharge sites. AFFF is the primary PFAS contamination risk at sites such as airports and military bases due to use as a fire extinguisher. Understanding the fate and transport of PFAS in the subsurface environment is a multifaceted issue. This review focuses on the role of adsorbent, adsorbate, and …


Evaluation Of Temperature-Index And Energy-Balance Snow Models For Hydrological Applications In Operational Water Supply Forecasts, Tian Gan, David G. Tarboton, Tseganeh Z. Gichamo May 2023

Evaluation Of Temperature-Index And Energy-Balance Snow Models For Hydrological Applications In Operational Water Supply Forecasts, Tian Gan, David G. Tarboton, Tseganeh Z. Gichamo

Civil and Environmental Engineering Faculty Publications

In the western United States, snow accumulation, storage, and ablation affect seasonal runoff. Thus, the prediction of snowmelt is essential to improve the reliability of water supply forecasts to guide water allocation and operational decisions. The current method used at the Colorado Basin River Forecast Center (CBRFC) couples the SNOW-17 temperature index snow model and the Sacramento Soil Moisture Accounting (SAC-SMA) runoff model in a lumped approach. Limitations in parameter transferability and calibration requirements for changing conditions with the temperature-index model motivated this research, in which new avenues were investigated to assess and prototype the application of an energy-balance snow …


Research And Application Of Dynamic Compaction Treatment Method For Highway Subgrade In Karst Development Area, Liu Xiaoming, Wang Yigang, Zhao Minghua May 2023

Research And Application Of Dynamic Compaction Treatment Method For Highway Subgrade In Karst Development Area, Liu Xiaoming, Wang Yigang, Zhao Minghua

Journal of China & Foreign Highway

This paper utilizes discrete-continuum coupled numerical simulation to investigate the failure modes of karst cave roofs with varying spans under specific compaction energy levels. The relationship between the span of the cave roof and the compaction energy required to cause roof collapse is established, providing an estimation method for the maximum unsupported span of cave roofs within the subgrade area. Based on this, the stability of karst cave foundations under the influence of subgrade loads can be evaluated. Depending on the results, a double-layer reinforced continuous concrete slab can be installed in the pavement base to enhance stability and mitigate …


Comparative Analysis Of Asphalt Pavement Performance Prediction Models Based On Gamma And Markov Processes, Ma Shibin, Chen Yonghao May 2023

Comparative Analysis Of Asphalt Pavement Performance Prediction Models Based On Gamma And Markov Processes, Ma Shibin, Chen Yonghao

Journal of China & Foreign Highway

Pavement performance prediction is a critical component of pavement management systems, serving as an essential basis and prerequisite for decision-making in asphalt pavement maintenance. This paper introduces the relevant theories of Gamma and Markov stochastic processes to construct asphalt pavement performance prediction models and address uncertainties related to pavement degradation. The results show that stochastic process models are effective in predicting pavement performance degradation and service life. Matlab programming was used to predict asphalt pavement performance and lifespan, yielding pavement degradation curves that significantly improve prediction accuracy and reliability. Finally, taking a test road section in Hebei Province as an …


Study On Interlayer Bonding Properties And Influence Factors Of Cape Seal, Li Yan, Zhang Chengxue, Qiu Yeji, Zhang Haijun May 2023

Study On Interlayer Bonding Properties And Influence Factors Of Cape Seal, Li Yan, Zhang Chengxue, Qiu Yeji, Zhang Haijun

Journal of China & Foreign Highway

To address pavement issues such as shoving and rutting caused by insufficient bonding strength in cape seal layers, this paper investigates the interlayer bonding properties and influencing factors of cape seal. Mechanical tests were conducted using a pavement interlayer shear-pull testing device. Through interlayer pull-off, direct shear, and torsional shear tests, the maximum tensile force, shear force, and torque at failure were obtained. The interlayer bonding performance of cape seal was analyzed in terms of gravel coverage rates, as well as upper and lower layer combinations. The results show that when the gravel coverage rate is 80%-90%, and the cape …


Fracture Mechanics‐Based Fatigue Study Of Corrugated Steel Webs, Li Haidi, Yang Lei May 2023

Fracture Mechanics‐Based Fatigue Study Of Corrugated Steel Webs, Li Haidi, Yang Lei

Journal of China & Foreign Highway

To develop fatigue analysis and evaluation methods for corrugated steel web structures, constant-amplitude fatigue load tests were conducted on experimental beam models, supplemented by fatigue test data from domestic and international studies. The finite element submodeling method was employed to obtain stress distribution functions at structural details, and the weight function method was used to derive the stress intensity factor at the crack tip. The Paris law in fracture mechanics was applied to derive the S-N curve for corrugated steel web structures. Comparative analysis with fatigue test results shows that when the initial crack depth is set as a0=t/20 (accounting …


Research On Multi‐Source And Heterogeneous Data Integration Of Large Bridge Health Monitoring System, Wang Daijun, Zhou Tiantu, Fu Junmin, Chen Xing, Lu Shuai, Yu Zheng May 2023

Research On Multi‐Source And Heterogeneous Data Integration Of Large Bridge Health Monitoring System, Wang Daijun, Zhou Tiantu, Fu Junmin, Chen Xing, Lu Shuai, Yu Zheng

Journal of China & Foreign Highway

Large bridge health monitoring systems are characterized by numerous sensors, diverse types, various communication methods, and flexible network configurations. The multi-source heterogeneous nature of the data poses significant challenges for data integration. To address the application requirements of bridge health monitoring, this paper designs a multi-source heterogeneous data integration scheme. The scheme achieves structured storage of multi-source heterogeneous data and introduces the concept of “structured communication.” This enables structured communication configuration, unified communication control, and flexible data processing, standardizing and simplifying communication configuration management in data acquisition systems. These improvements enhance code simplicity, maintainability, and the overall integration level of …


Selection And Design Of Anchorage For Suspension Bridge In Downhill Area Under Complex Geological Conditions, Chen Yongliang, He Shiyong, Xia Zhixian, Wu Wenxiang May 2023

Selection And Design Of Anchorage For Suspension Bridge In Downhill Area Under Complex Geological Conditions, Chen Yongliang, He Shiyong, Xia Zhixian, Wu Wenxiang

Journal of China & Foreign Highway

Due to the complexities of design and construction, long-span single-tower suspension bridges are rarely applied in practice. The main bridge of the Jinsha River Bridge at Tiger Leaping Gorge adopts a 766 m single-span single-tower steel truss suspension bridge. On the Lijiang anchorage side, complex geological conditions posed significant challenges due to geological structures, while the reservoir level of the planned hydropower station created adverse hydrological conditions for waterproofing and durability of the anchorage system. The selection of an appropriate anchorage type was therefore particularly challenging. This paper first details the selection process for anchorage under complex geological conditions. It …


Study On Countermeasures And Genetic Analysis Of Sloping Bridge Pile Hole Wall Failure, Yang Hua, Yin Xiaotao May 2023

Study On Countermeasures And Genetic Analysis Of Sloping Bridge Pile Hole Wall Failure, Yang Hua, Yin Xiaotao

Journal of China & Foreign Highway

The stability of slopes and the safety of bridge piles are interdependent, and ensuring the safety of sloping terrain is crucial for the safe construction of bridge piles. Based on three collapsed pile sections of the Huadizhai No. 2 Bridge, this paper utilized geological surveys to design initial terrain and altered terrain slope stability calculation conditions, along with horizontal compensation force calculation conditions under a safety standard of 1.35. By integrating geological analysis, slope stability assessment, and compensation force evaluations, the causes of pile hole collapse and corresponding countermeasures were analyzed. The results show that under the initial terrain, the …


Research On Gas Migration And Ventilation Disaster Prevention In Highway Tunnel, Wang Zhongqi, Lin Zhi, Feng Sen, Yang Hongyun, Chen Xiang, Liu Jiang May 2023

Research On Gas Migration And Ventilation Disaster Prevention In Highway Tunnel, Wang Zhongqi, Lin Zhi, Feng Sen, Yang Hongyun, Chen Xiang, Liu Jiang

Journal of China & Foreign Highway

To understand the gas migration patterns and ventilation disaster prevention techniques during tunnel construction, this paper uses a real tunnel as the engineering context. A 3D transient ventilation physical model was established using Ansys Fluent, and the effects of ventilation on gas concentration were analyzed in combination with on-site monitoring data. The results show that the uneven diffusion of gas and airflow is prominent. Gas concentration and wind speed stabilize at a distance of 120 m from the tunnel face as ventilation time increases. During gas monitoring and prevention, special attention should be paid to the area between the tunnel …


Research On Influence Factors And Efficiency Analysis Of Expressway Maintenance Marketization, Zhong Wen, He Shoukui, Wang Xiaodong May 2023

Research On Influence Factors And Efficiency Analysis Of Expressway Maintenance Marketization, Zhong Wen, He Shoukui, Wang Xiaodong

Journal of China & Foreign Highway

To promote market-oriented reform of highway maintenance, this paper investigates its influencing factors and outcomes and proposes an evaluation model for assessing its effects. A panoramic analysis method within a three-dimensional framework was employed to determine the evaluation content. Drawing on the balanced scorecard concept, the analysis incorporates four dimensions: business, user, internal management, and learning and growth, with the innovative addition of a social responsibility dimension to construct an evaluation indicator system. Subsequently, a cloud-based extension model was developed to evaluate the effectiveness of expressway maintenance marketization and calculate the evaluation grade. Empirical analysis was conducted using data from …


Study On The Minimum Radius Of Vertical Curve Of Highway Main Line Entrance Section Based On Merging Sight Distance, Li Yang, Zhao Yemei, Chen Tianxing May 2023

Study On The Minimum Radius Of Vertical Curve Of Highway Main Line Entrance Section Based On Merging Sight Distance, Li Yang, Zhao Yemei, Chen Tianxing

Journal of China & Foreign Highway

Given the limited research on the vertical curve radius of highway mainline entrance sections and the lack of differentiation between entrance and exit sections in existing studies, this paper identifies merging sight distance as the primary influencing factor for the vertical curve radius of entrance sections. Using merging sight distance as the control condition, the vertical curve radius of entrance sections was studied. A safety merging sight distance calculation model for highway mainline entrance sections was established by analyzing the traffic behavior characteristics of vehicles on the entrance mainline and considering drivers’ psychological and physiological characteristics. The sight distance model …


Inspection And Evaluation Of Load‐Bearing Capacity Of Hollow‐Box Arch Bridge, Song Zegang, Yang Min May 2023

Inspection And Evaluation Of Load‐Bearing Capacity Of Hollow‐Box Arch Bridge, Song Zegang, Yang Min

Journal of China & Foreign Highway

The inspection and evaluation of the load-bearing capacity of in-service bridges are crucial for ensuring structural and operational safety. This paper investigates a 90 m span hollow-box arch bridge, assessing its damage condition, material properties, and state parameters to determine partial evaluation coefficients. The bridge’s ultimate limit state and serviceability limit state load-bearing capacities of the main arch ring were then evaluated using both the original design standards and the current code. The results show that, compared to the original design standards, the safety factor for the compressive load-bearing capacity of the main arch ring cross-section is significantly reduced when …


Application Research And Prospect Of Passive Battered Pile, Zhou Dequan, Wang Chuangye, Zhou Yi, Zhao Yadang May 2023

Application Research And Prospect Of Passive Battered Pile, Zhou Dequan, Wang Chuangye, Zhou Yi, Zhao Yadang

Journal of China & Foreign Highway

Battered piles oriented in specific directions demonstrate superior horizontal load-bearing capacity compared to vertical piles. However, the working mechanism of battered piles remains inadequately understood, and corresponding design standards are yet to be established. These limitations hinder the effective utilization and application of the horizontal load-bearing and stability potential of battered piles. This paper comprehensively analyzes the soil-pile interaction mechanisms, horizontal displacement, and load-bearing behavior of passive battered piles and their composite systems under lateral unloading and lateral loading conditions, using model tests, numerical simulations, and theoretical analysis. In addition, it proposes future research directions aimed at advancing the study …


Study On Applicability Of Flexible Gabion Revetment In Soft Soil Subgrade In Lake District, Su Weiwei, Lei Mingxuan, Liu Guotian, Zhang Liujun, Liu Junyong May 2023

Study On Applicability Of Flexible Gabion Revetment In Soft Soil Subgrade In Lake District, Su Weiwei, Lei Mingxuan, Liu Guotian, Zhang Liujun, Liu Junyong

Journal of China & Foreign Highway

Based on FLAC3D finite difference software, this paper conducts numerical simulations of both flexible gabion revetment structures and rigid revetment structures to compare their deformation and stress characteristics. The results indicate that the flexible gabion revetment structure demonstrates excellent applicability for soft soil subgrades in lake districts. Compared with rigid revetment structures, the gabion revetment structure improves overturning stability through coordinated deformation within the foundation. It significantly reduces the basal stress, thus lowering the bearing capacity requirements for the foundation, and ensures a more uniform stress distribution at the base, minimizing differential settlement and enhancing foundation stability. Moreover, the gabion …


Study On Supporting Effect Of Pre‐Stressed Rock Bolts On Tunnel Face, Shen Xiangqian, Chen Daoyun, Zheng Chao May 2023

Study On Supporting Effect Of Pre‐Stressed Rock Bolts On Tunnel Face, Shen Xiangqian, Chen Daoyun, Zheng Chao

Journal of China & Foreign Highway

Focusing on the stability issues of the tunnel face in the large deformation section of soft rock in the Muzhailing Tunnel on the Weiyuan-Wudu Expressway, this paper proposes a technical solution for temporary reinforcement of the tunnel face using pre-stressed rock bolts. Numerical simulations were conducted to evaluate the reinforcement effect and effective range of pre-stressed rock bolts on the tunnel face, and the influence of initial ground stress on the reinforcement effect was further analyzed. The results show that under the given engineering conditions, pre-stressed rock bolts demonstrate significantly better reinforcement effects on the tunnel face compared to fully …


Study On Health State Evaluation Method Of Highway Tunnel Based On Neutrosophic Theory, Deng Fayou, Xia Caichu, Xu Chongbang May 2023

Study On Health State Evaluation Method Of Highway Tunnel Based On Neutrosophic Theory, Deng Fayou, Xia Caichu, Xu Chongbang

Journal of China & Foreign Highway

The structural complexity and inherent uncertainties of highway tunnels necessitate comprehensive consideration of various uncertain factors to reasonably evaluate their health state. By introducing neutrosophic theory, which accounts for structural uncertainties, this paper proposes a health state evaluation method for highway tunnels based on neutrosophic cosine and tangent similarity measures. The proposed method was applied to evaluate the health state of 10 samples. A comparison between the actual evaluation grades and the results obtained using the proposed method shows that the evaluation results are consistent with the actual grades. This indicates that the proposed method effectively addresses uncertainties in the …


Interlayer Bonding Performance Of Wtr/Apao Composite Modified Asphalt, Ji Hongyan, Yan Kezhen, Yuan Jian, Zhang Xuanyu May 2023

Interlayer Bonding Performance Of Wtr/Apao Composite Modified Asphalt, Ji Hongyan, Yan Kezhen, Yuan Jian, Zhang Xuanyu

Journal of China & Foreign Highway

To investigate the bonding performance of waste tire rubber (WTR)/ amorphous α-olefin copolymer (APAO) composite modified asphalt as a waterproof bonding layer in asphalt pavements on cement concrete bridges, shear and pull-off tests were conducted. The shear strength and pull-off strength of SBS-modified asphalt, WTR-modified asphalt, and WTR/APAO composite modified asphalt were compared under different application rates and temperatures. The results show that WTR/APAO composite modified asphalt exhibits the best bonding performance, followed by WTR-modified asphalt, with SBS-modified asphalt performing the worst. Based on the shear and pull-off strengths at different temperatures, the optimal application rates were determined as 1.7 …


Optimization Study On Indoor Vibratory Compaction Curves Of Cement Stabilized Macadam, Qiu Youqiang, Zhang Liujun May 2023

Optimization Study On Indoor Vibratory Compaction Curves Of Cement Stabilized Macadam, Qiu Youqiang, Zhang Liujun

Journal of China & Foreign Highway

To obtain well-defined secondary convex vibratory compaction curves and reduce the need for supplemental compaction point tests, this paper uses vibratory compaction tests for cement stabilized macadam in laboratory settings. Tests were conducted for two pavement sections along National Highway 110 (Hohhot to Bikeqi), exploring the influence of predefined moisture content intervals on vibratory compaction curves under varying cement dosages. The vibratory compaction curves were also compared with heavy compaction curves for analysis. The results show that the vibratory compaction curve is significantly influenced by the predefined moisture content intervals and cement dosage. For a moisture content interval of 1%, …


Study On Treatment Of Karst Foundation By Dynamic Compaction, Lyu Jiang, Zhao Hui, Yang Biao May 2023

Study On Treatment Of Karst Foundation By Dynamic Compaction, Lyu Jiang, Zhao Hui, Yang Biao

Journal of China & Foreign Highway

Dynamic compaction is a commonly used method for treating karst foundations with cavities; however, the design parameters of dynamic compaction under different working conditions lack clear standards. This paper employs the finite element software Abaqus to simulate the effects of surrounding rock quality and karst roof thickness on the stability of karst cave roofs during dynamic compaction treatment. The results indicate that the vertical displacement and maximum tensile stress of karst cave roofs are negatively correlated with roof thickness. For Grade II and III surrounding rocks with better properties, no cave collapse occurred after dynamic compaction treatment. In contrast, for …