Construction Engineering and Management Commons^™

Study On Relationship Of Solar Radiation Temperature And Pier‐Top Displacement Of Ultra‐High Thin‐Walled Hollow Pier, Liu Zhishen, Zhang Yifei, Song Fei, Su Jufeng, Ren Xiang

Journal of China & Foreign Highway

Thin-walled hollow piers are widely used in high-pier and long-span continuous rigid-frame bridges. Solar radiation-induced displacements at the tops of ultra-high thin-walled hollow piers can negatively affect the structural alignment and stress during construction and post-construction phases. Based on a 180 m high thin-walled hollow pier of a large bridge in Shaanxi Province, this paper analyzes the temperature field and pier-top displacement using data collected during two 24-hour periods: August 28-29 and October 11-12. The temperature field and pier-top displacement patterns over time were studied using finite element analysis. The results show that the temperature difference between the north and …

Model Test Study On Mechanical Characteristics Of Spherical Joints In Multi‐Point Support Swivel System, Zeng Lifei

Journal of China & Foreign Highway

As a critical load-bearing component in bridge swivel systems, the mechanical behavior of spherical joints is essential for the safety of bridge swiveling operations. This study focuses on the spherical joints of a multi-point support swivel system for the bridge over the Xiangyang North Marshalling Yard. Model tests were conducted to analyze the effects of the number of supporting legs, swivel speed, track smoothness, and wind load on the stress of spherical joints. The stress variation patterns of spherical joints under different working conditions were investigated. The results show that increasing the number of supporting legs improves the uniformity of …

Selection Of Phase Change Materials For Asphalt Pavement Based On Molecular Dynamics Simulation, Liu Fujun, Tian Xin, Liang Meichen, Guo Meng

Journal of China & Foreign Highway

Phase change materials (PCMs) have significant application potential in temperature regulation for asphalt pavements. To select suitable PCMs for road applications, this paper utilizes molecular dynamics simulation to analyze the molecular behaviors of lauric acid and polyethylene glycol (PEG). Experimental studies were conducted to validate the simulation results. The results show that molecular dynamics simulation provides an efficient and convenient method for comparing the performance of PCMs. PEG outperforms lauric acid in terms of molecular density, cohesive energy density, solubility parameters, and thermal conductivity, making it more suitable as a phase change material for asphalt pavements.

Study On Alkali Excitation Mechanism Of Large Dosage Slag Fine Powder, Mei Yang

Journal of China & Foreign Highway

To reveal the alkali excitation mechanism of high-dosage slag, this paper combines a three-factor, three-level orthogonal design with macro- and micro-performance tests and microstructure analysis. The effects of different activators, including Ca(OH)2, Na2SiO3, Na2SO4, and CaSO4, in single and dual combinations on the initial and final setting times, pore solution pH, and strength of concrete were explored. The results show that the impact on the strength of hardened paste of composite cementitious materials is ranked as: activator type > dosage > dual-mix ratio. The optimal dual-mix dosage is 4%, with the best combination being Ca(OH)2 and Na2SiO3 at a ratio of 5:1. …

Study On Microstructure Of Asphalt Modified By Oil‐Coal Blend, Guo Pengfei, Zhou Xinfeng

Journal of China & Foreign Highway

To investigate the microstructure and modification mechanism of asphalt modified with oil-coal blend, SK-90# asphalt was mixed with 5%, 10%, 15%, 20%, and 25% (external blending method) oil-coal blend to produce modified asphalt. The performance and microstructural changes of the modified asphalt were analyzed using contact angle testing, infrared spectroscopy, cross-sectional SEM, and X-ray photoelectron spectroscopy. The results show that the oil-coal blend exhibits good compatibility with asphalt. During the modification process, esterification reactions occurred, resulting in a decrease in hydroxyl-containing aromatic compounds and an increase in carbonyl-containing aromatic compounds. Macroscopically, the oil-coal blend-modified asphalt demonstrated excellent high-temperature performance.

Analysis Of Expressway Routine Maintenance Performance Management Based On Dea, Li Yuhuan, Shi Xiaoli, Gao Nan

Journal of China & Foreign Highway

To allocate maintenance resources efficiently and improve management levels, this paper examines the maintenance performance and improvement strategies of routine maintenance projects for 23 expressways in Shaanxi Province using 2018 operational maintenance data and data envelopment analysis. The results show that for some inefficient subsidiaries, traditional radial- and slack-based performance improvement methods are challenging and impractical in the short term. Therefore, a scenario-dependent model-based long-term incremental improvement strategy is proposed. By leveraging relative improvement values, this strategy enables phased improvements for inefficient subsidiaries. It provides a feasible approach for subsidiaries to set lower short-term performance improvement targets while achieving gradual …

Framework For Applicability Of Fidic Red Book (1999) For Contracts Governed By Law No. 182 Of The Year 2018 For Regulating Contracts Concluded By Public Entities, Fredy Ayad

Theses and Dissertations

An administrative contract is a type of contract that the administrative body enters in order to achieve a public interest. In Egypt, administrative contracts are governed by Law No. 182 of the year 2018 for Regulating Contracts concluded by Public Entities, which has been promulgated in October 2018. This Law includes several mandatory rules, which will govern over any conditions in the construction contract.

The FIDIC Red Book 1999 is widely used in Egypt and the Middle East in private sector and is currently also being utilized by governmental bodies. However, some contractors are not aware of the major deviations …

Reducing The Vulnerability Of Electric Power Infrastructure Against Natural Disasters By Promoting Distributed Generation, Gasser G. Ali, Islam H. El-Adaway, Charles Sims, J. Scott Holladay, Chien Fei Chen

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Natural disasters cause significant damage to the electrical power infrastructure every year. Therefore, there is a crucial need to reduce the vulnerability of the electric power grid against natural disasters. Distributed generation (DG) represents small-scale decentralized power generation that can help reduce the vulnerability of the grid, among many other benefits. Examples of DG include small-scale photo-voltaic (PV) systems. Accordingly, the goal of this paper is to investigate the benefits of DG in reducing the vulnerability of the electric power infrastructure by mitigating against the impact of natural disasters on transmission lines. This was achieved by developing a complex system-of-systems …

Development Of Self-Stressing Ultra High-Performance Concrete Using Expansive Chemical Admixtures, Lane Edwards

Graduate Theses and Dissertations

This study investigated the effects of expansive chemical admixtures on ultra-high performance concrete (UHPC) and self-stressing mechanisms. A literature review was performed to determine different types of expansive admixtures for feasibility of the self-prestressing concept. Ultimately it was decided that type-k cement, made by combining Komponent admixture with conventional UHPC, was the most suitable option due to its effects on wet and hardened concrete properties. Mix designs with varying amounts of Komponent were developed to test the effects the admixture had on various properties. Tested properties included, workability, compressive strength, expansion, short-term shrinkage, long-term shrinkage, and developed prestress. The development …

Systematic Literature Review Of Roof Systems On Energy Efficiency Of A Building To Support An Ideal Study Framework, Ayushi Raj Dua

All Theses

A sustainable building envelope is a crucial element to build energy efficient structures that contribute towards sustainable communities. The demand for sustainable building envelopes has grown in response to a growing emphasis on sustainable living. The roofing system is an important component of a sustainable building envelope because it influences the building's energy consumption and indoor comfort levels. The current study focuses on roofing systems and associated solar reflectance and albedo values to document the impact on energy efficiency via cooling/heating energy usage, dollar savings and temperature (ambient and surface) reductions due to the roofing systems. Additionally, the study focuses …

Floating Offshore Wind Turbine Project, Courtney Huitt, Cormack Williams

Civil and Environmental Engineering

Offshore wind is a developing industry in the Central Coast with the advent of the future offshore wind project planned off the north coast of San Luis Obispo County. This senior design project aligns with the recently leased wind energy project as a detailed study on the structural design, geotechnical design, and construction of a single 14 MW floating offshore wind turbine (FOWT) located 40 km NW of Morro Bay (NOAA buoy 46028). A preliminary design of a spar FOWT is presented in this project as a solution to the rapidly increasing water depth off the coast of Morro Bay, …

An Introduction To Autocad For Beginners, Zoe L. Mahaney

Construction Management

This paper aims to outline the process of developing and creating an online instructional video tutorial for beginner level individuals who hope to learn and utilize AutoCAD software. AutoCAD, developed by Autodesk, is a computer-aided design software that provides users with the ability to create and edit digital 2D and 3D designs, which is more efficient than traditional hand-drawn models. The main objective of this project is to provide the public with access to learning and navigating AutoCAD software on their own, for personal gain. Construction Management students at Cal Poly have the opportunity to learn and use AutoCAD as …

Personal Protective Equipment Usage And Injury Type, Nathan Giannini

Construction Management

Workers in the construction industry have many injuries both minor and life-altering. The industry suffers from injuries of all kinds such as falls, electrocution, and being struck by flying objects. To protect against this, workers wear certain types of personal protective equipment (PPE) on construction sites as a last line of defense. The equipment available such as hard hats, safety glasses, gloves, respirators, and hearing protection either protects against acute injuries (those that occur instantly) or chronic injuries (those that occur over time). This study investigates whether the type of injury that PPE protects against, acute or chronic, affects the …

Designing A Work-Life Balance Learning Module For Cal Poly Construction Management Department, Alex Jones

Construction Management

The construction industry is known to create a highly stressful work environment given its unpredictability and mental/time demanding nature, which creates challenges for professionals to maintain a healthy work-life balance. This senior project aims to research and identify the key areas that foster this stress and propose a learning module for the Cal Poly Construction Management Department to implement into class curriculum. Having this learning module taught to students will raise awareness of the topic for future industry professionals and equip them with the tools to maintain a healthy equilibrium between their work demands and personal life. The learning module …

Building Services Engineering May/June 2023

Building Services Engineering

No abstract provided.

Experimental Investigation Of The Self-Healing Potential Of Bacteria For Sustainable Concrete Structures, Pitiporn Asvapathanagul, Simone Galano, Andrea Calabrese, Mehran Rahmani, Maggie Ly, Daniela Flores, Michael Hernandez, Nicholas Banuelos

Mineta Transportation Institute

Although concrete is the most widely used building material in the world, its limited tensile strength makes cracking a common phenomenon in concrete elements. This study investigates the potential of autonomous self-healing as an eco-friendly and lowcost method to increase the durability of concrete. The crack-healing potential of different types of high-alkaline-tolerant bacteria or calcite-precipitation microorganisms is investigated. High-alkaline-tolerant bacteria and calcite-precipitation microorganisms were used to retrofit lab-fractured concrete samples. The samples healed with each of these bacteria groups were cast and tested under compressive load up to failure to measure the compressive strength of the concrete samples. The outcomes …

Effects Of Process Parameters On The Dimensional Accuracy Of Fused Deposition Modeled Parts, Ethan Eugene Bair

Theses and Dissertations

Fused deposition modelling (FDM) is one of the most common additive manufacturing techniques used with applications ranging from rapid prototyping at a professional scale to simple part creation at a hobbyist scale. FDM printing has very little in terms of information based on how accurate printed parts can be. This issue, which is common amongst many different types of additive manufacturing techniques, is something that has not been studied in FDM printed parts in high volumes. Research based on the effects of process parameters on mechanical properties has been conducted in high proportions. This study focused on FDM machines using …

A Step-By-Step Guide To Identify The Most Reliable Inventory Management System For Small Businesses Using Discrete Event Simulation And Pros And Cons Analysis: A Case Study At Camid-Florida Tech, Djalma Batista Oliveira Filho

Theses and Dissertations

According to the Department of Labor Statistics (2022), 20.6% of small businesses fail in their first year of operation, 42.6% fail after five years, and over 62.6% fail by their tenth year. One factor that can affect continued viability is the lack of knowledge and experience among small and medium-sized firms in inventory management. Despite the fact that inventory control is one of these businesses' most ignored management responsibilities, the expense of procuring inventory often accounts for a considerable portion of their budget. Due to poor inventory management or an inability to appropriately supervise their inventory, small firms may have …

Behavior Analysis Of Cement Concrete With Combination Of Waste Rubber And Glass, Abdulaziz Alebra

Symposium of Student Scholars

Glass and Rubber waste materials are valuable materials to use rather than throw which we have more than enough to use and recycle. Recycled glass and rubber materials can reduce and help major climate issues in our times based on the statistics reducing glass can bring down air pollution by 20% and also reduce water pollution by 50% as well as can reduce the use of landfill space. A laboratory study will be launched, and tests will be conducted following the ASTM standards, ASTM C143 for a concrete slump, and ASTM C31 for making and curing concrete specimens. Samples of …

Behavior Analysis Of Cement Concrete With Combination Of Waste Plastic And Glass, Mohamad Alamayreh

Symposium of Student Scholars

The waste stream in our society contains abundant plastic and glass waste, which can be effectively recycled to reduce the waste volume and save landfill space. Several studies have demonstrated that recycling glass can lower air pollution by 20% and water pollution by 50%, while recycling waste plastic can help reduce greenhouse gas emissions and save energy. To explore the potential use of recycled plastic and glass in concrete mixes, a laboratory investigation was conducted. Different percentages of plastic and glass waste will be tested as fine aggregates in cement concrete mixtures to evaluate their performance in terms of resistivity …