Construction Engineering and Management Commons^™

Mechanical Properties Of Alkali‑Activated Slag‑Fly Ash Geopolymers, Liu Yang, Wang Jizhao, Lu Naiwei, Wang Bowen

Journal of China & Foreign Highway

In order to respond to the national strategy of energy saving and emission reduction and improve the comprehensive utilization rate of industrial waste，the influence of slag content，alkali equivalent，sodium silicate modulus，and water-cement ratio on the compressive strength of slag-fly ash geopolymers was investigated by single variable and orthogonal experiment method.The compressive strength of geopolymers was analyzed by combining XRD，SEM，and porosity.The results show that the gel formation is promoted with the increase in slag content，and the structure of geopolymers is more compact，which is conducive to the development of strength.After 28 days of standard curing，the influence of various factors on the compressive strength …

Mechanical Properties Of Geopolymer‑Stabilized Recycled Aggregates From Construction Solid Wastes, Yuan Kaixin, He Yongjian, Zhang Laijun, Li Hai, Xu Gewei

Journal of China & Foreign Highway

In order to solve the problem of a sharp increase in construction solid wastes and insufficient utilization rate，this paper took slag-fly ash-based geopolymer as an inorganic binder，replaced natural gravels with recycled aggregates from construction solid wastes，and set urban road base layer as the target scene to study the mechanical properties of geopolymer-stabilized recycled aggregates at different contents.The results show that with the increase in geopolymer content，the maximum dry density of the mixture increases.The optimum moisture content increases.The unconfined compressive strength of the mixture increases with the increase in geopolymer content and curing age and decreases with the increase in recycled …

Comparative Experimental Study On Deformation Characteristics Of High Liquid Limit Soil Under Different Dry And Wet States, Qin Lingwei, Zhang Rui, Li Lu, Xiao Yupeng

Journal of China & Foreign Highway

In order to further reveal the internal mechanism of the influence of solid-like bound water on the deformation characteristics of high liquid limit soil，the difference in the influence of different bound water contents on the deformation of soil samples was analyzed through the comparison of dry and wet sides.Four types of high liquid limit soil with different water contents at the same dry density were used，and a low liquid limit soil was used as a comparison sample to carry out a deformation test.The volumetric flask method was used to test the content of adsorbed bound water in each test soil …

Influence Of Loading Methods On Compression Modulus Of Red Sandstone Soil Solidified With Biological Enzyme And Cement, He Liang, Zhang Haixiang, Guan H Ongxin, Li Huili, Yang Hairong, Liu Hongfu

Journal of China & Foreign Highway

There are various methods to test the modulus of cement-stabilized mixtures.The stiffness performance of cement-stabilized materials will be affected after adding biological enzymes.In order to systematically analyze the influence of loading conditions on the compression modulus of the red sandstone soil solidified with biological enzyme and cement，compressive modulus tests were conducted on the red sandstone soil solidified with biological enzyme and cement by using three static modulus test methods including monotonic loading method of middle section，stepwise loading and unloading method of top surface，and stepwise loading and unloading method of middle section，as well as dynamic modulus method of top surface and …

Optimization Of Mix Proportion For New Jersey Precast Concrete Safety Barriers And Performance Tests Under Integral Concrete Vibrating, Chen Lin, Li Beian, Li Yuanrui, Zhao Zixiang

Journal of China & Foreign Highway

New Jersey safety barriers are the most commonly used form of guardrails in highway median separators due to their excellent safety protection.In response to the cost reduction and quality improvement，efficient and rapid preparation process，and quality issues of New Jersey precast concrete safety barriers，this article adopted the automation production process of New Jersey precast safety barriers，optimized concrete mix proportion for precast safety barriers，and studied their performance.The experimental results show that in the designed C 30 concrete，the compressive strength of the concrete mixed with 15% fly ash reaches 39.2 MPa，and th e slump reaches 185 mm.The concrete performance meets the requirements of …

Experimental Study On Shear Behavior Between Nrc‑Uhpc Interface, Chen Zhenkan, Li Junsheng, Shi Quan, Fang Haozhen, Mo Fan, Jiang Haibo

Journal of China & Foreign Highway

In order to investigate the effect of the screw diameter of planted bars and ultra-high performance concrete （UHPC） pouring method on the shear behavior of normal reinforced concrete （NRC） and UHPC， two groups of six push-out specimens were designed for shear behavior tests.The results show that after the failure of the concrete bonding force in the NRC-UHPC interface，the screw can maintain shear behavior so that the failure process of the specimen after the load reaches the peak shows ductile characteristics.For specimens with screw diameters of 12 mm and 16 mm，greater screw diameter indicates higher shear capacity of the specimens and …

Design And Construction Process Of Cross‑Beam Supports For Main Tower Of Changtai Changjiang River Bridge, Zeng Jian, Hu Pei, Wang Chao

Journal of China & Foreign Highway

The construction of the lower cross-beam structure of the main tower of Changtai Changjiang River Bridge has the characteristics of high construction height，large amount of concrete earth volume，and difficult control of down-warping deformation.In order to implement the pouring of the lower cross-beam of the main tower，floor-type steel pipe supports were set at the lower cross-beam，which were used to support the lower cross-beam formwork and bear the load during the concrete pouring.Through the finite element software analysis and calculation，it was found that the asymmetric deformation of the main structure of the lower cross-beam could be effectively controlled，and the overall force of …

Determination Of Manufacturing Parameters Of Large Section Of Continuous Steel Box Beam With Variable Section In Shenzhen‑Zhongshan Passage, Dong Chuangwen, Chen Long, Li Chuanxi

Journal of China & Foreign Highway

Accurate calculation of manufacturing parameters is the key to the efficient，high-precision，and rapid installation of large sections of continuous steel box beam bridges.Taking the steel box beam with the variable section in Shenzhen-Zhongshan Passage as the background，this paper first established a finite element model of the beam element in the whole construction process to obtain the pre-camper.Secondly，the average neutral axis position was calculated based on the height of the neutral axis of each beam section.Then，according to the deformation characteristic that the beam length remained unchanged at the mean neutral axis，the pre-camber was superimposed at the mean neutral axis to get the …

Key Technology For Construction Of New Single‑Wall Steel Suspended Box Cofferdam With High Pile Tied Beams In Deep Water, Yang Jinlong, Zhao Lin, Jiang Qunlong

Journal of China & Foreign Highway

In order to ensure the safe，efficient，and economical completion of the construction of the high pile tied beam of Muping Xiangjiang River Bridge in deep water，a new type of single-wall steel suspended box cofferdam was designed to act as the water retaining and enclosure structure during high pile tied beam construction according to the characteristics of deep water level and shallow stratum cover layer at the high pile tied beam location.Through the innovative design of steel casing on the bottom of the steel suspended box cofferdam，the design height of the wall panel and the amount of steel input were reduced.On the …

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 …

Construction Site Planning And Logistical Operations: Site-Focused Management For Builders, Second Edition, Randy R. Rapp, Bradley L. Benhart

Purdue Handbooks in Building Construction

Organizing and administering a construction site so that the right resources get to the right place in a timely fashion demands strong leadership and a well-defined, disciplined process. Good logistical operations enable profitability, and this book is the essential, muddy boots guide to such management. Written by experienced educator–practitioners, Construction Site Planning and Logistical Operations is a popular guide to the knowledge, skills, and abilities needed by project superintendents, especially, but useful to all constructors. This second edition is updated to include new technologies, resources, and details of operational planning. Leadership imperatives and management techniques remain integrated throughout. The book …

How Will Ai Impact Knowledge Sharing Within Construction Clustering? Bringing Back The Conversation On Social Contagion Within Construction Clusters, Oluwasegun O. Seriki, Mark Mulville, Ruairi Hayden

Conference Papers

Construction clusters and innovation systems play a crucial role in enhancing competitiveness and fostering sustainable development in the construction sector. These clusters facilitate knowledge sharing, interactive learning, and collaborative innovation among firms, institutions, and other stakeholders. The success of construction clusters depends on numerous factors, including firm size, economic climate, and attitudes towards innovation. While some clusters transform into innovation systems by becoming tacit-knowledge intensive, there is not much data or investigation into how they may adapt to changing demands spurred by advances in artificial intelligence (AI). There is some preliminary research highlighting the lack of dispersed innovation networks within …

Leveraging Machine Learning For Defect Detection In Irrigation Concrete Canal Lining In Egypt: Advancing Construction Quality And Efficiency, Mohamed Nabawy

Civil Engineering

Abstract:

Defects during the construction phase of projects pose significant challenges, particularly in terms of

safety, cost overruns, delays, and labor inefficiencies. In irrigation concrete canal lining construction

with mega investments, early detection of defects is critical to ensuring quality and project success.

This study explores the application of machine learning (ML) for onsite defect detection, focusing

on the development and deployment of an object detection mobile application specifically tailored

for identifying visible defects in concrete canal lining construction. Leveraging the machine learning

capabilities of Microsoft Azure, a custom object detection model was trained and validated to

recognize defects such …

Increasing Drift Capacity Of Non-Ductile Concrete Shear Walls Through Confinement With Fiber-Reinforced Polymer Application, Andrew Duong, Sophia Maglabe, Sheyna Rongong

Architectural Engineering: Graduate Reports

The seismic response and laboratory testing of pre-1980s reinforced concrete (RC) shear walls commonly exhibit undesirable concrete crushing and rebar buckling in the wall end-zones leading to a flexural compressive failure. The lack of ductility of these walls is attributed to low reinforcement ratios and absence of special boundary elements (SBE) as required by modern design code. Thus, the authors are proposing a fiber reinforced polymer (FRP) retrofit method to provide confinement to the end-zones of pre-1980s walls equivalent to that of an SBE. Current industry applications of FRP have largely been for shear strengthening of RC beams, columns, and …

Life-Cycle Cost Analysis Of Fm4 Txdot Roadway Alternatives In Cleburne, Texas, Ethan A. Bright

2024 Fall Honors Capstone Projects - Archive

The Engineering senior design group proposed a three-span concrete bridge, merged lane intersection, and a single storm conduit system. The Honors contribution to this project was analyzing the design’s alternative’s life-cycle costs to compare the most economic design. The project’s cost consists of initial construction, maintenance, and decommission. Utilizing Texas Department of Transportation (TxDOT) bid code unit prices, each design alternative is calculated by multiplying each material amount by the unit price then summed. Although the parallel conduit system has a cheaper initial cost, it requires more maintenance during its lifetime, therefore the single conduit system was recommended. Notably, cost …

Assessing The Critical Factors Influencing Worker Safety In Roadway Work Zones, Bahaa Chammout, Muaz O. Ahmed, Islam El-Adaway

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Ongoing roadway construction and maintenance activities are essential for sustaining and improving infrastructure. Nonetheless, work zones in the United States continue to experience concerning frequencies of occupational and traffic accidents. Previous research highlighted multiple factors influencing work zone safety, yet their relative impact and importance remain unclear. This study addresses this gap following a multistep methodology. First, 32 safety factors were identified through an extensive literature review in a previous study. Second, a survey was administered among 298 professionals from diverse backgrounds, with an average of 17.75 years of construction experience and 13.78 years of work zone experience, to assess …

Collision Hazard Prevention And Notification For Construction Worker Safety Using Audio Surveillance, Kehinde Elelu

All Dissertations

The construction industry faces significant safety challenges, with collision hazards ranking as the second highest cause of annual fatalities and injuries in the United States, as reported by the Occupational Safety and Health Administration (OSHA). Current collision detection methods predominantly rely on proximity technologies, which necessitate costly and complex installations on each construction equipment piece. Furthermore, auditory situational awareness declines among workers due to hearing loss and intricate construction noises, which further heightens collision risks. This research introduces an innovative, low-cost, audio-based collision prevention technology aimed at enhancing auditory situational awareness for construction workers exposed to high noise levels. The …