Other Civil and Environmental Engineering Commons^™

Influence Factors Of Carbonization Of Tunnel Segment Structure And Life Prediction Analysis, Li Dongbiao, Miao Miao, Shen Caihua, Chen Wei

Journal of China & Foreign Highway

There are many factors that affect the carbonization life of concrete segments in underwater tunnels，and the prediction methods are not uniform.In this paper，combined with actual engineering，the influencing factors and laws of carbonization of concrete segments in underwater tunnels were analyzed，and three methods for predicting the life of concrete segments were established with the crack limit as the control target.The prediction results of the three methods were compared.The results show that the influence of the temperature and CO2 concentration in the tunnel predicted by the three methods on the life of the tunnel lining structure is basically consistent with the existing …

Key Technology For Incremental Launching Construction Of Double Guide Beam Of Steel Box Girder, Sun Xiaoqiang, Yue Xinxing

Journal of China & Foreign Highway

By taking the incremental launching construction of the steel box girder at the 6th hole of the approach bridge of Baoji Taigu Bridge as the engineering background，the original plan adopted single-guide beam multi-point walking incremental launching technology for assembly and incremental launching on the prestressed reinforced concrete beam of the adjacent hole.Since the middle span of the concrete beam cannot withstand the concentrated force at the incremental launching points，the multi-guide beam multi-point walking incremental launching technology was finally used to arrange the incremental launching points at the transverse diaphragm plate of the end of the concrete beam.By increasing the incremental …

Emergency Vehicle Dispatching Model Considering Demand Urgency And Delivery Fairness, Long Kejun, Liu Jia, Gao Zhibo, Chen Suqian, Zhang Zhonggen

Journal of China & Foreign Highway

In emergency vehicle dispatching after unexpected events，it is crucial to prioritize critical nodes with high demand urgency while minimizing excessive delivery delays at other nodes to prevent secondary impacts.On this basis，this study developed an emergency vehicle dispatching model that considered demand urgency and delivery delay fairness.Firstly，the entropy weight-TOPSIS method was used to calculate the demand urgency for each node，and a delivery delay balance index was introduced to minimize disparities in delivery delays between nodes.Secondly，a multi-objective optimization model was established with total delivery time，overall cost，and delivery delay balance as objectives，while considering constraints such as inventory levels at distribution centers and route …

Working Properties Of Steel Tube Batter Piles With Concrete Infill Based On Abaqus, Yang Meiliang, Li Liemin, Sun Kunjiang, Han Rui, Zhong Yang

Journal of China & Foreign Highway

In order to explore the respons e characteristics of steel tube batter piles with concrete infill under vertical load，the steel tube batter pile with concrete infill used in Saribas Bridge in Malaysia was taken as the research object.Based on the numerical simulation method，the frictional resistance of the inner and outer walls of the steel tube，the frictional resistance around the pile at the section，and the bending moment bearing ratio between the steel tube and the concrete core of this type of batter pile under vertical load were studied.The results show that the passive-side frictional resistance of the 0–15 m pile section …

Impacts Of Stream Bed Adjustment On Local Bridge Morphology At Highway 281, Molly G. Likins

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Nebraska sand-bed rivers have long been a part of sediment transport studies and have been used in the development of numerous well-known empirical bedload equations. Some of these studies have shown how adjustments in streambed elevation led to changes in local stream morphology. The sand-bed rivers of Nebraska are highly susceptible to such changes due to their wide, shallow cross-sections and erodibility. The objective of our study is to synthesize a hydrodynamic model with high-resolution field data and improved methods of representing sediment transport to better predict both short and long-term channel adjustments for an aggraded sand-bed river.

The field …

Numerical Study On The Behavior Of Natural And Recycled Aggregate Concretes, Shahriar Mardpour

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

This thesis investigates the mechanical behavior of natural and recycled aggregate concretes (NAC and RAC) using a multi-phase numerical approach to predict performance. Growing interest in sustainable materials has led to using recycled concrete aggregates (RCA) to replace natural aggregates, creating Recycled Aggregate Concrete (RAC). Due to their different structural components, RAC and NAC exhibit varying mechanical properties, particularly in strength and durability.

This study validated tension and bending (flexural) test models by comparing numerical results with similar models from the literature. Following validation, a multi-phase approach modeled NAC and RAC for the bending (flexural) and tension tests, providing a …

Development And Evaluation Of Highly Thixotropic Uhpc Mixtures For Bridge Overlay Applications, Akbota Aitbayeva

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Ultra-high-performance concrete (UHPC) is an advanced construction material renowned for its exceptional strength and durability. However, conventional UHPC is typically self-consolidating, making it unsuitable for bridge deck overlay applications due to challenges posed by potential surface slopes. UHPC overlay construction requires a highly thixotropic material that not only responds well to vibration but also maintains workability over an extended period and remains stable on sloped surfaces. Despite the complex rheological properties of highly thixotropic UHPC, limited testing methods are available to effectively assess the workability and rheology of overlay mixtures. To address this gap, the present study provides a comprehensive …

Exploring Variably Saturated Flow Formulations For Modflow: Implementing A Fully 3d Richards' Equation In Modflow 6, Sebastian Vazquez-Gasty

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

This thesis explores the implementation of a fully 3D Richards’ equation solution into MODFLOW 6 to solve for saturated/unsaturated flow. Currently, MODFLOW 6 has limited capability for solving unsaturated zone flow problems by using the Unsaturated Zone Flow (UZF) package, which neglects capillarity and assumes vertical 1-dimensional flow. Various formulations of the Richards’ equation were first evaluated for their strengths and weaknesses. Various numerical solution approaches to Richards’ equation were also studied to understand the robustness and efficiency of different approaches and to select one that would best fit into the MODFLOW 6 framework. The MODFLOW 6 framework was also …

Quality Assurance Of Cast-In-Place Foundation Elements, Tristen Mee

USF Tampa Graduate Theses and Dissertations

Construction of cast-in-place concrete deep foundation elements is a common practice, yet performed almost entirely blind, leaving uncertainty in the quality of the as-built, below-ground element. This dissertation focuses on three quality assurance aspects of cast-in-place foundations: an automated concrete tracking system for drilled shafts, an alternate approach to identifying if mass concrete conditions exist in cast-in-place foundations, and as-built auger cast pile grout volume determination.

The volume of concrete in a drilled shaft is relatively easy to track on a truck-by-truck basis, as well as the height of the rising concrete per truck. However, a more detailed volume distribution …

Internet Of Things-Based Automated Solutions Utilizing Machine Learning For Smart And Real-Time Irrigation Management: A Review, Bryan Nsoh, Abia Katimbo, Hongzhi Guo, Derek M. Heeren, Hope Njuki Nakabuye, Xin Qiao, Yufeng Ge, Daran R. Rudnick, Joshua Wanyama, Erion Bwambale, Shafik Kiraga

Department of Agricultural and Biological Systems Engineering: Faculty Publications

This systematic review critically evaluates the current state and future potential of real-time, end-to-end smart, and automated irrigation management systems, focusing on integrating the Internet of Things (IoTs) and machine learning technologies for enhanced agricultural water use efficiency and crop productivity. In this review, the automation of each component is examined in the irrigation management pipeline from data collection to application while analyzing its effectiveness, efficiency, and integration with various precision agriculture technologies. It also investigates the role of the interoperability, standardization, and cybersecurity of IoT-based automated solutions for irrigation applications. Furthermore, in this review, the existing gaps are identified …

Treatment Methods Of Unstable Expansive Soil Slope Excavation In Overlying Rock Layer In Alpine Region, Shi Xiaobo, Cui Guangyan, Mou Chao, Wen Ye, Xie Feng, Fu Xiaoyang

Journal of China & Foreign Highway

To deeply study the treatment method for instability of highway cutting slope under the condition of expansive soil overlying rock layer in an alpine region，the comprehensive treatment method of unstable slope under this bad geology was put forward based on the unstable slope project of Zhangbei‒Shangyi Expressway.The governance protection structure consisted of a rigid protection system，drainage system，thermal insulation system，flexible protection system，and waterproof system.The rigid protection system was an anti-slide pile setting at the height of 1/3 of the first grade slope，of which parameters were calculated by cutting the slope of the rock layer in the unstable area to reduce the …

Treatment And Measurement Of Water Inrush During Highway Tunnel Construction, Wang C Haojie, Feng Zhihua, Fan Haobo

Journal of China & Foreign Highway

As a special geological condition of highway tunnels，water inrush will cause difficulties in engineering construction technology and management.Unnecessary disputes and management difficulties will emerge when different construction units hold different views about the treatment measures of water inrush，which leads to distributed provisions in the specification and a long treatment period.In view of key problems about the water inrush during highway tunnel construction，including water inrush treatment concept，investigation and estimation，measurement and pricing，and on-site confirmation，this paper systematically sorted out the current regulations and other guiding documents and investigated the treatment methods of tunnel water inrush and reverse slope pumping in China ’s highway …

Review Of Evaluation Methods For Mixing Workability Of Asphalt Mixture, Dong Fuqiang, Zu Yuanzhe, Yu Xin, Chen Bei, Liu Lin

Journal of China & Foreign Highway

To clarify the evaluation methods an d research status of mixing workability of asphalt mixture， by consulting relevant research literature in China and abroad and analyzing different evaluation methods，indexes，and research findings of the workability of asphalt mixture，the applicability and evaluation effects of different workability evaluation methods were systematically summarized，and the comparative analysis and comprehensive review were made on the main influencing factors of the mixing workability.The results show that in most evaluation methods for the mixing workability of asphalt mixture，corresponding indexes are constructed to quantitatively evaluate the workability by quantifying the resistance or energy consumption in the mixing process.Besides，in some …

Research Review Of Biomass Ash As Concrete Admixture, Ma Bicong, Liang Jian, Weng Yiling

Journal of China & Foreign Highway

In order to provide a comprehensive overview of research progress in the use of biomass ash as concrete admixture，the physical and chemical properties，mechanism of action，factors affecting the production process of biomass ash，and the effects of biomass ash incorporation on the working properties，mechanical properties，and durability of concrete were studied.The results show that biomass ash has a smaller density and a larger specific surface area than traditional mineral admixture，and the total amount of active components，namely SiO2 + Al2O3 + Fe2O3 （SAF） in most biomass ashes exceeds the requirements of class F volcanic ash （≥70%）.Incorporating biomass ash can effectively improve the mechanical properties …

Compaction Characteristics Of Granular Material And Its Structural Mechanical Behavior Considering Orthotropy, Huang You, Zhang Yunbao, Liu Zhaohui, Pan Yu, Liu Zebin, Fang Ronghai

Journal of China & Foreign Highway

The orthotropy of granular materials is closely related to the compaction process and has a significant impact on the mechanical behavior of pavement structures.In this study，in order to study the effect of the compaction process on the orthotropy of granular materials，different compaction methods and compaction energies were employed to compact granular materials for pavement into specimens，and improved dynamic resilient mechanical tests were conducted.Orthotropic coefficients （α2） of typical granular materials were obtained，and the finite element method was used to conduct mechanical analysis of asphalt pavement structures considering the orthotropy of granular materials.The results show that the dry density of specimens by …

Effect Of Basalt Fiber On Strength Of Cement‑Stabilized Macadam Base, Shu Hongbo, Tang Zhengguang, Zhang Yanhong, Bu Xilian, Liang Dong

Journal of China & Foreign Highway

To study the performance of basalt fiber in improving the poor angularity of the crushed cobble base，based on the orthogonal test，this paper determined that the optimal dosage of basalt fiber in the cement-stabilized crushed cobble was 1 kg/m3 （15 mm） + 2 kg/m3 （25 mm）.Besides，unconfined compressive strength and splitting strength tests were carried out on mixtures under three working conditions including the cement-stabilized crushed cobble，cement-stabilized crushed cobble with the optimal dosage of basalt fiber，and cement-stabilized macadam （limestone machine-crushed stone ）.The results show that influenced by the aggregate angularity，the strength of the cement-stabilized macadam （limestone machine-crushed stone ） mixture is better …

Design And Simulation Of Anti‑Collision System On Independent Pile With External Composite, Liao Yuanyuan, Liu Yu, Zhu Lu, Fang Hai, Zhang Jinrui, Han Juan

Journal of China & Foreign Highway

The precise calculation of the ship-bridge collision force is necessary for the assessment of the structural safety of the bridge and the design of an effective anti-collision system.Taking the ship-bridge issue in Furong Bridge in Xiangtan City，this paper compared the collision forces from different angles and in different locations calculated through the finite element software Ansys/LS-DYNA with the results calculated through the empirical formula，thereby determining the fortification collision forces of the bridge piers.Based on the weak anti-collision ability of the bridge double-limb thin-walled pier，the paper designed and implemented a new anti-collision system combined with composite and concrete-filled steel independent piles.The …

Intelligent Recognition Technology Of Highway Cracks Based On Semantic Segmentation, Gao Liang, Rao Faqiang, Yang Zhongmin, Dai Zongsheng, Sun Hao

Journal of China & Foreign Highway

Real-time detection and timely treatment of highway cracks are crucially fundamental for vehicle safety.Rapid identification and comparison of cracks is a new method for monitoring the development and changes of geological disasters especially when they induce cracks.Therefore，this study proposed an intelligent recognition method of highway cracks based on semantic segmentation，establishing a model with dataset，neural network，calculation parameters，and evaluation indicators to rapidly identify the cracks.The results show that，firstly，when the neural network Attention U-net built in this study semantically segments highway cracks，the binary cross loss function value and accuracy rate reach 0.008 7 and 0.998 4，respectively.Secondly，compared with traditional algorithms，the semantic segmentation method shows …

Lessons Learned From 60 Years Of Pavement Trials In Continental Climate Regions Of Canada And Future Perspective, Wang Di, Li Jingxiao, Ren Xueyuan, Zhang Fan, Yuan Dongdong

Journal of China & Foreign Highway

During the early 1960 s，Canadian road authorities began using stiffer asphalt to address the issue of early rutting in the wheel track zone of asphalt pavements，which was caused by the growing traffic volumes.Pavements constructed with stiffer asphalt commonly exhibit evenly spaced transverse cracks due to the significant internal stresses caused by low temperatures and the inadequate resistance of the asphalt to cracking under such conditions.Research conducted on asphalt pavements with cracks caused by low temperatures has verified the significant impact of asphalt ’s consistency，temperature sensitivity，phase uniformity，and durability.In order to tackle the difficulties presented by the utilization of modified asphalt in …

Method Of Solving Initial Construction Cable Force Of Completed Cable‑Stayed Bridge, Xu Yufeng, Chen Si, Xie Yunfei, Zhu Mengyang

Journal of China & Foreign Highway

To solve the initial construction cable forces of a completed cable-stayed bridge，a method that combines unstressed cable length and forward-iteration is proposed.Firstly，the unstressed length of each cable is calculated according to the completed bridge state.Then，the initial cable forces are obtained by using the unstressed cable length for the forward analysis.The initial construction cable forces are adjusted by difference iteration.Finally，the initial construction cable forces are fine-tuned according to the deformation of the pylon deformation to obtain the bridge completion state that satisfies the deviation requirements.The proposed method is employed in a cable-stayed bridge with a known completion state to calculate the …

Experimental Study On Influence Of Stress Ratio On Fatigue Life Of High Strength Steel Wire, Zeng Yi, Yan Donghuang, Xu Hongsheng, Yang Ying

Journal of China & Foreign Highway

To clarify the influence of stress ratio on the fatigue life of high strength steel wire and verify the applicability of the fracture mechanics model to evaluate the fatigue life of steel wire，based on the assumption of equating wire corrosion pits to notches，fatigue tests were carried out on steel wire samples with different prefabricated notch depths at different stress ratios，and a fatigue life empirical equation considering the stress ratio effect was established.The results show that the fatigue life of the steel wire samples is significantly influenced by the stress ratio，which decreases with the increase in the stress ratio.The increase in …

Influence Of High Temperature On Large Cantilever Construction Control Of Wide Extradosed Cable‑Stayed Bridge, Zhu Haojie, Zhang Xiedong, Li Yong, Lin Yuan, Wu Di

Journal of China & Foreign Highway

In order to investigate the influence of temperature gradient on the construction of wide extradosed cable-stayed bridges in the large cantilever construction stage at high temperatures，the solar radiation and thermal boundary conditions of wide equal-height box girder were theoretically calculated，and the thermal analysis finite element model of the wide equal-height box girder was established by Abaqus.The cross-section temperature of the box girder was measured by intelligent string sensors and an infrared thermometer.The temperature gradient and its distribution of wide equal-height box girder from sunrise to sunset on a certain day in summer were calculated.The finite element model of the construction …

Back‑Calculation Of Subgrade Modulus Based On Genetic Algorithm And Viscoelasticity Theory, Dai Fugui, Wang Xihui, Wu Yaguang, Li Hai

Journal of China & Foreign Highway

To improve the applicability of the PFWD detection method for the back-calculation of subgrade modulus，taking the subgrade splicing project of the west loop line in Nairobi as an example，this paper adopted 3D Kelvin viscoelasticity model and quasi-static response analysis to deduce the displacement function of viscoelastic subgrade under long-term fixed loads，and combined the principle of liner superposition of viscoelasticity with genetic algorithm to propose a new method based on multi-population genetic algorithm for the modulus back-calculation of viscoelastic subgrade.Among them，the corresponding program for back-calculation was written by Matlab.The comparison between theoretical derivation and field tests shows that the peak value …

Overall Design Concept Of Municipal Reconstruction Of Cross‑City Expressway, Fu Yuankun, Zhang Yu

Journal of China & Foreign Highway

The municipal reconstruction of the cross-city expressway is of great significance in enlarging the urban framework，refining the spatial pattern，and promoting the integrated development of clusters.However，China’s expressways seldom undergo municipal reconstruction，with less synergy formed with cities.Therefore，taking one case described above in Hebei Province as an example，this article proposed the overall design concept of integrating with the city from urban space，road networks，municipal facilities，urban ecology，cultural landscape，and other perspectives after analyzing problems in urban space，traffic，industry，landscape and urban quality in existing cross-city expressways. In addition，this paper studied and optimized the municipal reconstruction plan.Holding a theme of “municipalization ”，the plan eliminated the fragmentation of urban space …

Progress And Prospects Of Road Engineering Disease Treatment Technology In Permafrost Regions, Gao Feng, Zeng Xianzhang, Zhong Wenhua, Huang Shengyong, Zhang Junhui

Journal of China & Foreign Highway

Freeze-thaw disasters are key issues affecting the service performance and operational safety of road projects in permafrost regions.Under the combined influence of warming and humidification of the permafrost environment and engineering thermal effects，the degradation of permafrost is accelerating，exacerbating the risk of road freeze-thaw diseases.Roads in these regions are more frequently maintained and repaired to ensure service performance，with a service life lower than designed.Therefore，deepening the understanding of the disaster mechanism of road geotechnical structures and strengthening the study on engineering disease treatment technology are of great significance in promoting the construction and maintenance of high-quality and high-grade highways in frozen regions.This …

Model Test On Soil Deformation Mechanism And Damage Mode Caused By Mud Leakage From Drilled Piles In Karst Area, Jiang Mingying, Chen E ’Mei, Liu Yongcheng, Zhu Yadong, Jiang Wenkui, Xie Ruiting

Journal of China & Foreign Highway

Pile holes are often drilled through cavities in karst areas，which induces mud leakage and causes hole wall instability，ground collapse，or equipment trapping and hinders smooth construction.It is important to know the collapse mechanism of boreholes due to mud leakage，so as to optimize and determine the construction process of pile holes.In this paper，indoor model tests were used to study the deformation mechanism and damage mode of soil caused by drilling through cavities and mud leakage in pile holes under the conditions of upper clay and lower sandy soil in the karst area，so as to provide an experimental basis for the decision of …

Deformation Measurement And Safety Warning Of Highway Bridges Based On Machine Vision, Su Ziyue, Du Wenkang, Lei Dong

Journal of China & Foreign Highway

The structural safety of highway bridges plays a crucial role in traffic safety operations and regional economic development.Due to the rapid increase and complex changes in traffic loads，the demand for real-time monitoring of bridge ’s structural deformation and safety conditions has been increasingly prominent.However，the structural health monitoring system，dominated by contact sensors，has limitations such as difficult installation and construction，complicated maintenance and replacement，and the need to interrupt traffic.To this end，a non-contact deformation measurement system based on machine vision was proposed.Template matching and feature point recognition methods were utilized to achieve recognition of structural surface markings and displacement extraction of key positions.The accuracy …

Properties And Application Of Cement Improved Loess Under Low Temperature Environment In Cold Region, Li Xiangyang

Journal of China & Foreign Highway

According to the cold climate and low annual average temperature in cold regions of China，the field curing conditions of cement improvement of collapsibility loess under low temperature，room temperature，and medium temperature were simulated at 5 ℃，10 ℃，20 ℃，and 30 ℃，respectively.Based on laboratory experiments，this study analyzed the effects of curing temperature，cement content，and curing age on RCBR，unconfined compressive strength，and dynamic resilience modulus of cement improved loess.The effects of cement content and curing temperature on freeze-thaw durability and erosion resistance of cement improved loess were studied by the freeze-thaw cycle test and dynamic water erosion test.Combined with the laboratory results，the 4% and 5% cement …

Effect Of Chloride Ions On Salt Expansion Of Salinized Subgrade Fill Soil In Cold Regions, Hu Wenzhu, Wang Zhaowei, Cao Yong, Zhang Jing, Bai Ruiqiang

Journal of China & Foreign Highway

Salinized subgrade fill soil in cold regions typically comprises composite saline soil rich in sodium chloride and sodium sulfate.This study aimed to explore the mechanism of the effect of chloride ion content on salt expansion of the salinized subgrade in cold regions.Based on the calculation theory of the sodium chloride-sodium sulfate-water ternary system solution in the Pitzer ion model and combined with the FREZCHEM model，the study quantitatively analyzed the intrinsic connection between water activity，freezing factor，and supersaturation ratio with temperature and concentration ratio （η=mCl-/mSO2-4）.It investigated the variation patterns of the freezing temperature and crystallization supersaturation ratio of composite saline soil with …

Correlation Between Pavement Distress And Structural Hidden Distress, Liu Xianming, Xia Han, Hu Dongping, Yan Chen, Yang Rui, Zhong Xinran

Journal of China & Foreign Highway

The hidden distress in the pavement structure does great harm to the performance and service life of the road.In this work，based on the statistical idea of pavement distress rate in the Highway Performance Assessment Standards （JTG 5210—2018），an index of characterizing hidden distress in the pavement structure，namely pavement structure distress rate，was proposed.Based on the actual highway inspection project，the pavement distress and the hidden distress in the depth of 1 m below the pavement of a two-way four-lane highway with a length of 38 km were studied.The overall situation of pavement distress and hidden distress and their spatial distribution were analyzed statistically …