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2018

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Articles 451 - 480 of 555

Full-Text Articles in Civil Engineering

Viability Of Graywater Reuse In Lesotho’S Lowland Agricultural District, Ryan Wagner Jan 2018

Viability Of Graywater Reuse In Lesotho’S Lowland Agricultural District, Ryan Wagner

Dissertations, Master's Theses and Master's Reports

Water security has become a large issue with populations rising and weather patterns changing to drier and hotter conditions in southern Africa. Lesotho, a mountainous country landlocked by South Africa, is responsible for a large amount of the rainfall in southern Africa. As such, Lesotho provides water to South Africa in exchange for national economic growth. Lesotho, however, is also prone to droughts and with water reserves being sold to South Africa, water security has become a national issue. This study looked at Lesotho’s current water use habits and found that graywater reuse could lead to much more available water. …

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Modified Design Procedures For Bridge Pile Foundations Subjected To Liquefaction-Induced Lateral Spreading, Arash Khosravifar, Jonathan Nasr Jan 2018

Modified Design Procedures For Bridge Pile Foundations Subjected To Liquefaction-Induced Lateral Spreading, Arash Khosravifar, Jonathan Nasr

Civil and Environmental Engineering Faculty Publications and Presentations

Effective-stress nonlinear dynamic analyses (NDA) were performed for piles in the liquefiable sloped ground to assess how inertia and liquefaction-induced lateral spreading combine in long- and short-duration motions. A parametric study was performed using input motions from subduction and crustal earthquakes covering a wide range of durations and amplitudes. The NDA results showed that the pile demands increased due to (a) longer duration shakings, and (b) liquefaction-induced lateral spreading compared to nonliquefied conditions. The NDA results were used to evaluate the accuracy of the equivalent static analysis (ESA) recommended by Caltrans/ODOT for estimating pile demands. Finally, the NDA results were …

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Inertial And Liquefaction-Induced Kinematic Demands On A Pile-Supported Wharf: Physical Modeling, Milad Souri, Arash Khosravifar, Stephen E. Dickenson, Scott Schlechter, Nason Mccullough Jan 2018

Inertial And Liquefaction-Induced Kinematic Demands On A Pile-Supported Wharf: Physical Modeling, Milad Souri, Arash Khosravifar, Stephen E. Dickenson, Scott Schlechter, Nason Mccullough

Civil and Environmental Engineering Faculty Publications and Presentations

Results of a centrifuge test on a pile-supported wharf were used to investigate the time-, depth-, and row-dependent nature of kinematic and inertial loading on wharf piles in sloping rockfill. P-y models were calibrated against recorded bending moments in different piles and different depths. It was found that full kinematic demands and full superstructure inertia should be combined to estimate bending moments at pile head and shallow depths (less than 10 diameters below the ground surface). On the contrary, it was found that applying full kinematic demands alone was adequate to estimate pile bending moments at large depths (greater than …

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The Effects Of Long-Duration Subduction Earthquakes On Inelastic Behavior Of Bridge Pile Foundations Subjected To Liquefaction-Induced Lateral Spreading, Jonathan Nasr, Arash Khosravifar Jan 2018

The Effects Of Long-Duration Subduction Earthquakes On Inelastic Behavior Of Bridge Pile Foundations Subjected To Liquefaction-Induced Lateral Spreading, Jonathan Nasr, Arash Khosravifar

Civil and Environmental Engineering Faculty Publications and Presentations

Effective-stress nonlinear dynamic analyses (NDA) were performed for a large-diameter reinforced concrete (RC) pile in multi-layered liquefiable sloped ground. The objective was to assess the effects of earthquake duration on the combination of inertia and liquefaction-induced lateral spreading. A parametric study was performed using input motions from subduction and crustal earthquakes covering a wide range of motion durations. The NDA results showed that the pile head displacements increased under liquefied conditions, compared to nonliquefied conditions, due to liquefaction-induced lateral spreading. The NDA results were used to develop a displacement-based equivalent static analysis (ESA) method that combines inertial and lateral spreading …

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Development Of Models And Solution Methods For Different Drayage Applications, Samaneh Shiri Jan 2018

Development Of Models And Solution Methods For Different Drayage Applications, Samaneh Shiri

Theses and Dissertations

In the last decades, intermodal freight transport is becoming more attractive in the global supply chains and freight transport policy makings. Intermodal freight transport provides a cost-effective, reliable, and efficient movement of freight by utilizing the strengths of different transport modes. The initial and final segment of intermodal freight transport, performed by truck, is known as “drayage.” The scheduling of truck movements in drayage operation within the service area of an intermodal terminal is an operational problem which leads to a truck scheduling problem that determines the efficient schedule of trucks while satisfying all transportation demands and constraints. Drayage accounts …

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Computations Of The Dynamic Fracture Of Plane Structures By The Extended Finite Element Method, Iman Asareh Jan 2018

Computations Of The Dynamic Fracture Of Plane Structures By The Extended Finite Element Method, Iman Asareh

Theses and Dissertations

Finite element methods for the simulation of dynamic fracture in plane structures are presented. The method is a modified extended finite element method (XFEM) for dynamic fracture simulations with a new methodology to construct the XFEM basis functions for discontinuities. In contrast to conventional XFEM in which the extended interpolation is defined to only capture the discontinuities, the proposed method describes the enrichment functions so that they reproduce both the discontinuities and the polynomial bases of sufficiently high order which are critical for finite element convergence. Such enrichment functions, by adopting the Duffy’s transformation, can be simply defined in terms …

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Assessing Exposure To Occupants In An Indoor Space Due To Expirated Aerosols: Application Of Computational Fluid Dynamics, Firoza Binte Omar Jan 2018

Assessing Exposure To Occupants In An Indoor Space Due To Expirated Aerosols: Application Of Computational Fluid Dynamics, Firoza Binte Omar

Theses and Dissertations

Indoor environment is an important issue for the well-being of the society. In the United States more than 90% people spend their time indoor, indoor air pollution is more culpable than the pollution outside air. Two third of US businesses lose more than $100,000 per year due to workplace related illness. The trend of sharing the work space has an impact on total sick leaves in a company. Infectious particles released by a flu sufferer’s sneezing, coughing or even laughing can be a vital source. A thorough analysis on infectious particles’ transmission and air flow of the space can provide …

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Understanding Geopolymerization Process For Enhancement Of Mechanical Properties Of Fly Ash Based-Geopolymer Concrete, Lateef Najeh Assi Jan 2018

Understanding Geopolymerization Process For Enhancement Of Mechanical Properties Of Fly Ash Based-Geopolymer Concrete, Lateef Najeh Assi

Theses and Dissertations

Concrete is a major construction material that is largely made up of cement. Unfortunately, the manufacturing process for the cement currently used to produce concrete releases a great deal of CO2, which endangers the environment. Hence, finding alternatives to ordinary Portland cement is of extreme importance. The intellectual contribution of this dissertation is the development of an improved understanding of the geopolymerization process so that the compressive strength of cement can be maximized while the need for external heating is minimized. The intent is to create a substance to replace commonly used cement without sacrificing other beneficial properties. The first …

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Evaluation Of Sonocatalytic Degradation Of Ibuprofen And Sulfamethoxazole In The Presence Of Various Catalysts, Yasir Alhamadani Jan 2018

Evaluation Of Sonocatalytic Degradation Of Ibuprofen And Sulfamethoxazole In The Presence Of Various Catalysts, Yasir Alhamadani

Theses and Dissertations

Over the last two decades, large quantities of products, such as medicines, disinfectants, and personal care products, have been released into surface waters and wastewater treatment facilities by the pharmaceutical and chemical industries which have come to the attention of scientists with regard to their impacts on life in lakes, rivers, and groundwater. Among various types of treatment processes, ultrasonic (US) treatment process was used in this study to investigate the effect catalysts and removal of selected pharmaceutical’s (PhACs) compounds (ibuprofen (IBP) and sulfamethoxazole (SMX)). Carbon nanomaterials (CNMs) have become candidates for numerous applications in nanocomposites, microelectric devices, sensors, energy …

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Effect Of Vessel-Generated Waves In Near Low Tide Conditions On Shorelines In The Intracoastal Waterways, Mackenzie Lee Sanchez Jan 2018

Effect Of Vessel-Generated Waves In Near Low Tide Conditions On Shorelines In The Intracoastal Waterways, Mackenzie Lee Sanchez

UNF Graduate Theses and Dissertations

Erosion is caused when there is a net loss of sediment in a coastal system, i.e. when the amount of sediment leaving a system is more than the amount of sediment entering that same system. This investigation will focus on vessel-generated waves and their effect on the shorelines of the Jacksonville, Florida Intracoastal Waterways near low tide conditions. The investigation conducted herein examines variations in turbidity and pressure measurements in response to passing vessels at a single site location previously selected in 2016. The primary water/shoreline interaction recorded during this investigation is located below the visible scarp (near low tide …

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Development Of Forward And Inversion Schemes For Cross-Borehole Ground Penetrating Radar, Donald Jones Jan 2018

Development Of Forward And Inversion Schemes For Cross-Borehole Ground Penetrating Radar, Donald Jones

UNF Graduate Theses and Dissertations

Tomography is an imaging technique to develop a representation of the internal features of material using a penetrating wave, such as an electromagnetic wave. The calculation method used is an example of an inverse problem, which is a system where the input and the output are known but the internal parameters are not. These parameters can be estimated by understanding the responses of a penetrating wave as it passes through the unknown media. A forward problem is just the opposite; the internal structure and input penetrating wave is known and the output is determined. For both forward and inverse problems, …

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Probabilistic Multilevel Constitutive Model Of The Compressive Strength Of Hardened Cement Paste Reinforced With Mwcnts, Yohanna Mejia Cruz Jan 2018

Probabilistic Multilevel Constitutive Model Of The Compressive Strength Of Hardened Cement Paste Reinforced With Mwcnts, Yohanna Mejia Cruz

Theses and Dissertations

Constitutive models available in the literature typically describe the compressive strength of ordinary Portland cement paste (OPC) in a deterministic fashion, in some cases as a function of variables such as W/C, porosity, and the clinker chemical composition. The significant effect of the proportion of W/C on the final strength, porosity and density have been reported in several works in material science. Some studies have shown that the addition of MWCNTs can also modify the microstructure of cement significantly, and improve compressive strength and other mechanical and physical properties. In principle, W/C, MWCNTs addition, porosity, density, and compressive strength are …

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Hydrothermal Carbonization Of Food Waste For Nutrient Recovery And Reuse, Ifeolu M. Idowu Jan 2018

Hydrothermal Carbonization Of Food Waste For Nutrient Recovery And Reuse, Ifeolu M. Idowu

Theses and Dissertations

Food waste represents a rather large and currently underutilized source of potentially available and reusable nutrients. Laboratory-scale experiments evaluating the hydrothermal carbonization of food wastes collected from restaurants were conducted to understand how changes in feedstock composition and carbonization process conditions influence primary and secondary nutrient fate. Results from this work indicate that at all evaluated reaction times and temperatures, the majority of nitrogen, calcium, and magnesium remain integrated within the solid-phase, while the majority of potassium and sodium reside in the liquid-phase. The fate of phosphorus is dependent on reaction times and temperatures, with solid-phase integration increasing with higher …

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Nondestructive Evaluation Of Corrosion Damage In Reinforced Concrete Aged Slab Specimen, Rawya Abdulsattar Abduljabbar Jan 2018

Nondestructive Evaluation Of Corrosion Damage In Reinforced Concrete Aged Slab Specimen, Rawya Abdulsattar Abduljabbar

Theses and Dissertations

The deterioration of concrete bridge decks presents a maintenance challenge for most transportation agencies and bridge owners. This problem increases during the freeze-thaw cycle. De-icing salts can accelerate the deterioration process. Corrosion of steel reinforcement in reinforced concrete structures is considered a dominant factor causing premature deterioration, especially those structures located in a coastal environment. The resulting corrosion product produced has several times the volume of steel, resulting in cracking of the concrete cover if the corrosion is significant. In this study, a bridge deck specimen was subjected to an artificial environment to accelerate the corrosion process. Prior to this …

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Impact Of Critical Path Method (Cpm) Of Scheduling On On-Time Completion Of Transportation Projects, Fahim Ahmed Jan 2018

Impact Of Critical Path Method (Cpm) Of Scheduling On On-Time Completion Of Transportation Projects, Fahim Ahmed

Theses and Dissertations

This study addresses the effectiveness of Critical Path Method (CPM) scheduling on project delivery. Specifically, the on-time completion of projects with and without a CPM schedule is explored. The paper uses data from 2,097 South Carolina transportation projects let after February 2008 and substantially completed by August 2015. The delay analysis uses the original contract completion date as well as the completion date adjusted by change orders. Chi-Squared tests are used to examine the relationship between CPM scheduled projects and delayed projects, and t-tests are used to compare the mean delay (in days) between CPM scheduled and unscheduled projects. The …

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Designing And Testing 3-D Printed Wafer-Box With Embedded Pzt Sensors To Identify The Shape Effect On Energy Harvesting, Ahmad Jami Safayet Jan 2018

Designing And Testing 3-D Printed Wafer-Box With Embedded Pzt Sensors To Identify The Shape Effect On Energy Harvesting, Ahmad Jami Safayet

College of Graduate Studies: Theses & Dissertations

Piezoelectric energy has been recently paid attention in the field of alternative energy. Day by day the traditional energy sources including Coal tar and oils are becoming scarce. People are heading to an alternative energy source to meet the future energy demand. Piezoelectric energy is one of the competitive energy sources compared to the conventional renewable energy sources including solar, wind, and geothermal power and so on. This energy production method bears enormous research potential because it can be used as the roadway for a new method of power generation. This research project aimed to identify which shaped wafer-box produced …

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การวิเคราะห์ปัจจัยที่ส่งผลต่อการเชื่อฟังของผู้ขับขี่ที่มีต่อป้ายขีดจำกัดความเร็วแบบปรับเปลี่ยน, กนกวรรณ ศรีเสาวกาญจน์ Jan 2018

การวิเคราะห์ปัจจัยที่ส่งผลต่อการเชื่อฟังของผู้ขับขี่ที่มีต่อป้ายขีดจำกัดความเร็วแบบปรับเปลี่ยน, กนกวรรณ ศรีเสาวกาญจน์

Chulalongkorn University Theses and Dissertations (Chula ETD)

งานวิจัยนี้มีจุดประสงค์เพื่อศึกษาการตัดสินใจของผู้ขับขี่ยานพาหนะเมื่อเห็นป้ายขีดจำกัดความเร็วแบบปรับเปลี่ยนและวิเคราะห์ความสัมพันธ์ระหว่างปัจจัยต่างๆและการเชื่อฟังของผู้ขับขี่ที่มีต่อป้ายขีดจำกัดความเร็วแบบปรับเปลี่ยน โดยศึกษาจากกลุ่มผู้ขับขี่รถยนต์ภายในกรุงเทพมหานครจากแบบสอบถามออนไลน์ ตัวแปรที่ใช้ในการศึกษา ได้แก่ คุณลักษณะเศรษฐกิจสังคม คุณลักษณะพฤติกรรมการใช้ความเร็วและคุณลักษณะสถานการณ์การขับขี่ ในการวิเคราะห์ข้อมูลโดยใช้วิธีสถิติพรรณนาและแบบจำลองสมการถดถอยโลจิสติก ผลการวิจัยจากกลุ่มตัวอย่างจำนวน 907 ตัวอย่างพบดังนี้ 1) การตัดสินใจใช้ความเร็วเมื่อพบป้ายขีดจำกัดความเร็วแบบปรับเปลี่ยนส่วนใหญ่ตัดสินใจชะลอความเร็วแต่จะใช้ความเร็วไม่ถึงป้าย 2) การเปลี่ยนช่องจราจรส่วนใหญ่ไม่คิดเปลี่ยนช่องจราจร 3) ความเร็วเฉลี่ยหลังผ่านป้ายขีดจำกัดความเร็วแบบปรับเปลี่ยนที่ตั้งใจใช้อยู่ที่ 93.44 กิโลเมตรต่อชั่วโมง 4) การเชื่อฟังป้ายขีดจำกัดความเร็วแบบปรับเปลี่ยนส่วนใหญ่ตัดสินใจไม่เชื่อฟัง 5) การวิเคราะห์แบบจำลองความถดถอยโลจิสติกพบว่า ปัจจัยที่มีอิทธิพลต่อการเชื่อฟังป้ายขีดจำกัดความเร็วแบบปรับเปลี่ยน ได้แก่ เพศ อายุ การตัดสินใจของยานพาหนะคันหน้า ความเร็วเฉลี่ยที่ใช้ประจำบนทางพิเศษ การได้รับใบสั่งจากการใช้ความเร็วเกินกฎหมายกำหนดและการประสบอุบัติเหตุในช่วง 3ปี โดยปัจจัยที่มีอิทธิพลต่อการเพิ่มการเชื่อป้ายหลักคือ เพศ การได้รับใบสั่งจากการใช้ความเร็วเกินกฎหมายกำหนดแลละการตัดสินใจชะลอความเร็วของยานพาหนะคันหน้าเมื่อเห็นป้ายขีดจำกัดความเร็ว

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การวิเคราะห์เส้นโค้งปฏิสัมพันธ์กำลังของเสาเหล็กเซลลูลาร์, จักรภัทร พันธรักษ์พงษ์ Jan 2018

การวิเคราะห์เส้นโค้งปฏิสัมพันธ์กำลังของเสาเหล็กเซลลูลาร์, จักรภัทร พันธรักษ์พงษ์

Chulalongkorn University Theses and Dissertations (Chula ETD)

วิทยานิพนธ์นี้นำเสนองานวิจัยเกี่ยวกับการวิเคราะห์กำลังรับแรงอัดกระทำเยื้องศูนย์ของเสาเหล็กเซลลูลาร์ด้วยแบบจำลองไฟไนต์เอลิเมนต์ 3 มิติโดยใช้โปรแกรม ABAQUS โดยในแบบจำลองได้คำนึงถึงความไม่สมบูรณ์เชิงเรขาคณิตและหน่วยแรงคงค้าง และตรวจสอบความถูกต้องของแบบจำลองเสาเซลลูลาร์ด้วยสมการทำนายการโก่งเดาะแบบอิลาสติกสำหรับเสาเซลลูลาร์ ในการวิเคราะห์เสาเซลลูลาร์และเสาหน้าตัดตั้งต้นรับแรงอัดภายใต้แรงกระทำเยื้องศูนย์ สามารถสร้างเส้นโค้งปฏิสัมพันธ์กำลังรับแรงอัดตามแนวแกนและแรงดัดร่วมกัน จากการเปรียบเทียบผลการวิเคราะห์แรงอัดกระทำเยื้องศูนย์ด้วยวิธีไฟไนต์เอลิเมนต์ของแบบจำลองเสาหน้าตัดตั้งต้นกับการวิเคราะห์กำลังด้วยสมการเส้นโค้งปฏิสัมพันธ์อ้างอิงตามข้อกำหนด AISC-2016 พบว่า ผลการวิเคราะห์จากแบบจำลองให้เส้นโค้งปฏิสัมพันธ์กำลังต้านทานแรงอัดร่วมกับแรงดัดที่ใหญ่กว่าสมการตามข้อกำหนด และเมื่อเปรียบเทียบผลการวิเคราะห์แรงอัดกระทำเยื้องศูนย์ระหว่างหน้าตัดเซลลูลาร์และหน้าตัดตั้งต้น พบว่าเสาเหล็กเซลลูลาร์มีกำลังต้านทานแรงอัดร่วมกับแรงดัดต่ำกว่าเสาหน้าตัดตั้งต้นเมื่ออัตราส่วนความชะลูดมีค่าต่ำกว่า 1.0 แต่มีกำลังต้านทานแรงอัดร่วมกับแรงดัดสูงกว่าเสาหน้าตัดตั้งต้นเมื่ออัตราส่วนความชะลูดมีค่ามากกว่าเท่ากับ 1.0 นอกจากนี้ งานวิจัยนี้ได้เสนอแนวทางการสร้างเส้นปฏิสัมพันธ์กำลังสำหรับเสาเหล็กเซลลูลาร์ซึ่งเมื่อตรวจสอบกับผลการวิเคราะห์จากแบบจำลองไฟไนต์เอลิเมนต์ พบว่า ผลจากแบบจำลองไฟไนต์เอลิเมนต์ให้กำลังต้านทานแรงอัดร่วมกับแรงดัดของเสาเซลลูลาร์ต่ำกว่าแนวทางการวิเคราะห์ที่เสนอเมื่ออัตราส่วนความชะลูดมีค่าต่ำกว่า 0.5 แต่เมื่ออัตราส่วนความชะลูดมีค่าเท่ากับ 1.0 ให้กำลังที่ใกล้เคียงแนวทางการวิเคราะห์ในบางกรณีของอัตราส่วนขนาดช่องเปิดและให้กำลังที่มากขึ้นสำหรับอัตราส่วนความชะลูดเท่ากับ 1.5 และ 2.0 ตามลำดับ

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พฤติกรรมการยึดเหนี่ยวระหว่างแผ่นพอลิเมอร์เสริมเส้นใยคาร์บอนและคอนกรีตโดยใช้อีพอกซีเสริมท่อนาโนคาร์บอน, อมเรศ มธุรส Jan 2018

พฤติกรรมการยึดเหนี่ยวระหว่างแผ่นพอลิเมอร์เสริมเส้นใยคาร์บอนและคอนกรีตโดยใช้อีพอกซีเสริมท่อนาโนคาร์บอน, อมเรศ มธุรส

Chulalongkorn University Theses and Dissertations (Chula ETD)

งานวิจัยนี้มีวัตถุประสงค์เพื่อศึกษาพฤติกรรมการยึดเหนี่ยวระหว่างแผ่นพอลิเมอร์เสริมเส้นใยคาร์บอน (CFRP) และคอนกรีตโดยใช้อีพอกซีเสริมท่อนาโนคาร์บอน (CNTs) โดยมีตัวแปรที่ใช้ในการศึกษา คือประเภทของท่อนาโนคาร์บอน ประกอบด้วย แบบผนังชั้นเดียว (SWCNTs) และแบบผนังหลายชั้น (MWCNTs) ปริมาณของท่อนาโนคาร์บอนที่ปริมาณ 0.25, 0.50, 1.00 และ 2.00% ของปริมาณอีพอกซี และประเภทของอีพอกซี ประกอบด้วยอีพอกซีชนิดค่าความหนาแน่นเท่ากับ 1.30 และ 1.65 กิโลกรัมต่อลิตร ผลการศึกษาพบว่าพลังงานการต้านทานการแตกหักที่ผิวสัมผัสและหน่วยแรงยึดเหนี่ยวสูงสุดมีค่าเพิ่มขึ้นสูงสุด 51.11% และ 56.47% ตามลำดับ เมื่อใช้ SWCNTs ที่ 1.00% ของปริมาณอีพอกซีในอีพอกซีค่าความหนาแน่น 1.30 กิโลกรัมต่อลิตร อย่างไรก็ตามการใช้ SWCNTs และ MWCNTs เสริมอีพอกซีที่ความหนาแน่น 1.65 กิโลกรัมต่อลิตร มีแนวโน้มให้พลังงานการต้านทานการแตกหักที่ผิวสัมผัส หน่วยแรงยึดเหนี่ยวสูงสุด รวมถึงค่าการเลื่อนไถลสูงสุดที่ลดลง สำหรับรูปแบบการหลุดล่อนโดยส่วนใหญ่มีการแยกตัวที่วัสดุประสานและคอนกรีต ทั้งนี้การใช้อีพอกซีที่ความหนาแน่น 1.65 กิโลกรัมต่อลิตร โดยการใช้อีพอกซีเสริม SWCNTs ที่ปริมาณ 0.25% ของปริมาณอีพอกซี มีการหลุดล่อนจากการสูญเสียการยึดเหนี่ยวของวัสดุเชื่อมประสาน และการใช้ MWCNTs 0.25% ของปริมาณอีพอกซีมีการหลุดล่อนจากการแตกหักของคอนกรีต จากการตรวจสอบการยึดเหนี่ยวภายในชั้นของอีพอกซีและการยึดเหนี่ยวของอีพอกซีกับ CFRP ด้วยกล้องจุลทรรศน์อิเล็กตรอนแบบสแกน พบว่าให้ผลสอดคล้องกับผลของหน่วยแรงยึดเหนี่ยวสูงสุด โดยผลของชุดทดสอบที่มีหน่วยแรงยึดเหนี่ยวสูง มีลักษณะการยึดเกาะหรือการรวมตัวของอีพอกซีที่ดีและช่องว่างของอีพอกซีน้อย จึงแสดงให้เห็นถึงประสิทธิภาพของท่อนาโนคาร์บอนที่มีการปรับปรุงคุณสมบัติของอีพอกซี

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Development Of Causal Relationship Model Of Knowledge Sharing In Construction Projects, Lambada Roeun Jan 2018

Development Of Causal Relationship Model Of Knowledge Sharing In Construction Projects, Lambada Roeun

Chulalongkorn University Theses and Dissertations (Chula ETD)

Knowledge sharing among construction project members is very crucial for improving project success and project performance. It can also reduce mistakes in the construction process. Project management has been growing more complicated, and project members need to learn best practice from others. Currently, knowledge sharing is not well performed yet; especially, few research studies have been focused on the relationship evaluation of supporting factors that affect knowledge sharing from different contexts in construction projects. Therefore, this study aims to develop the causal relationship model of supporting factors from psychological, individual, organizational, and technological factors that affect mediators – knowledge sharing …

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Collaborative Strategies For Sea Level Rise Adaptation In Hampton Roads, Virginia, Carol Considine, Emily Steinhilber Jan 2018

Collaborative Strategies For Sea Level Rise Adaptation In Hampton Roads, Virginia, Carol Considine, Emily Steinhilber

Engineering Technology Faculty Publications

[Introduction] The Hampton Roads region is located in southeastern Virginia where the Chesapeake Bay meets the Atlantic Ocean. The region includes seventeen municipal governments and has a large federal government presence with 26 federal agencies represented (See Figure 1). The region has a population that exceeds 1.7 million and is home to the deepest water harbor on the U.S. East Coast. Hampton Roads' economy is dependent on the local waterways and houses the world's largest naval facility, the sixth largest containerized cargo complex and supports a thriving shipbuilding and repair industry as well as a tourism industry. However, the region's …

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Evaluation Of Driver Behavior At Highway-Railroad Grade Crossings Based On Environmental Conditions And Driver Demographics, Alawudin Salim Jan 2018

Evaluation Of Driver Behavior At Highway-Railroad Grade Crossings Based On Environmental Conditions And Driver Demographics, Alawudin Salim

Dissertations, Master's Theses and Master's Reports

Although the total number of highway-railroad grade crossing (HRGC) accidents has significantly decreased in recent decades, they remain as one of the highest causes of injuries and fatalities in rail transportation. It is known that driver behavior is the leading cause for accidents at HRGCs, but there is less understanding on the reason for these inappropriate behaviors. This research uses the Strategic Highway Research Program 2 Naturalistic Driving Study (SHRP 2 NDS) data and a behavior scoring methodology developed at Michigan Technological University (Michigan Tech), to evaluate driver behavior when traversing HRGCs. More specifically, it uses a two-sample t-test to …

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Analysis Of Cracked Body Repaired By Adhesively Bonded Patches By Bem-Fem Coupling, Binh Viet Pham Jan 2018

Analysis Of Cracked Body Repaired By Adhesively Bonded Patches By Bem-Fem Coupling, Binh Viet Pham

Chulalongkorn University Theses and Dissertations (Chula ETD)

This thesis presents an efficient numerical technique capable of handling the stress analysis of three-dimensional cracked bodies strengthened or repaired by adhesively bonded patches. The proposed technique is implemented within the framework of the coupling of the weakly singular boundary integral equation method and the standard finite element procedure. The former is applied to efficiently treat the elastic body containing cracks whereas the latter is adopted to handle both the adhesive layers and the patches. The approximation of the near-front relative crack-face displacement is enhanced by using local interpolation functions that can capture the right asymptotic behaviour. This also offers …

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The Relationship Of Influential Factors On Material Management Effectiveness In Building Construction Projects: Case Study In Vietnam, Bao Van Pham Jan 2018

The Relationship Of Influential Factors On Material Management Effectiveness In Building Construction Projects: Case Study In Vietnam, Bao Van Pham

Chulalongkorn University Theses and Dissertations (Chula ETD)

The improvement of management processes in construction could be seen as one of the important keys to project success in which material management should be appropriately taken into consideration. Although many previous research studies have examined the components of construction material management, the relationship of factors influencing material management effectiveness has not been explored. This study was carried out to identify influential factors on material management effectiveness and develop a model to explain the relationships between these factors and the effectiveness of material management based on practical projects. The research method included the collection of contractors' opinions in building projects …

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Sbfe Analysis Of Layered Elastic Media With Consideration Of Surface Energy Effect, Chantha Chhuon Jan 2018

Sbfe Analysis Of Layered Elastic Media With Consideration Of Surface Energy Effect, Chantha Chhuon

Chulalongkorn University Theses and Dissertations (Chula ETD)

This thesis presents an efficient and accurate numerical technique for determining mechanical response of a two-dimensional, infinite, elastic, layered medium under arbitrary surface loading and surface stress effects. Governing equations of a generic bulk layer are formulated from the classical linear elasticity theory via a SBFE technique whereas those of the generic material surface are obtained from a full version of Gurtin-Murdoch surface elasticity theory. The formulation is established sufficiently general allowing both homogenous and functionally graded bulk materials to be treated for each layer. By enforcing the continuity at the interface of the material surface and the bulk, it …

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Compression Behavior Of Fire-Damaged Concrete-Filled Steel Tubular Columns Confined With Fiber-Reinforced Polymer Sheets, Dat Thanh Vu Jan 2018

Compression Behavior Of Fire-Damaged Concrete-Filled Steel Tubular Columns Confined With Fiber-Reinforced Polymer Sheets, Dat Thanh Vu

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research investigates the axial compression behavior of fire-damaged circular concrete-filled steel tube (CFST) stub columns externally confined with fiber-reinforced polymer (FRP) sheets. A total of 38 CFST specimens were tested under axial compression to investigate the load capacity, ductility, stiffness and failure mode of fire-damaged CFST columns before and after strengthening with FRP sheets. The test variables include the level of fire damage (no damage and 2-hour ISO standard fire), compressive strength of infill concrete (24MPa and 55MPa), type of FRP sheets (carbon and glass), and the number of FRP layers (0, 1, and 2 layers). The test results …

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A Bim-Database-Integrated System For Evaluating Building Life-Cycle Costs Using A Multi-Parametric Model, Hang Thi Thu Le Jan 2018

A Bim-Database-Integrated System For Evaluating Building Life-Cycle Costs Using A Multi-Parametric Model, Hang Thi Thu Le

Chulalongkorn University Theses and Dissertations (Chula ETD)

Life-cycle cost analysis (LCCA) has become an essential requirement of the sustainable procurement for many construction projects. Conventional building LCCA methods are extremely complex and time-consuming due to repetitive works, numerous required data, scattered data inputs, and various regulatory requirements, which subsequently lead to inaccurate building life-cycle costs (LCC). Building information modeling (BIM) offers a revolutionary information technology, which can overcome the asperities of the conventional building LCCA. This research develops the BIM-database-integrated system for evaluating building life-cycle costs using a multi-parametric model (BIM-BLCC). The BIM-BLCC consists of four interrelated modules. The relational database management module collects and organizes the …

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Improved Response Spectrum Analysis Procedure For Design Of Reinforced Concrete Tall Buildings, Kimleng Khy Jan 2018

Improved Response Spectrum Analysis Procedure For Design Of Reinforced Concrete Tall Buildings, Kimleng Khy

Chulalongkorn University Theses and Dissertations (Chula ETD)

Response spectrum analysis (RSA) procedure commonly used in design practice has been found to underestimate design forces in tall buildings. Failure and damage of reinforced concrete (RC) shear walls in mid-rise and high-rise buildings have been observed in recent earthquakes. In this dissertation, a modified RSA (MRSA) procedure to compute shear forces and strains in RC walls and columns to identify locations requiring ductile detailing was proposed. Six tall RC shear-wall buildings of 15 to 39 stories and four RC moment-frame buildings of 3 to 15 stories subjected to earthquake ground motions expected in Bangkok and Chiang Mai were first …

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Development Of Causal Relationship Model Of Knowledge Sharing In Construction Projects, Lambada Roeun Jan 2018

Development Of Causal Relationship Model Of Knowledge Sharing In Construction Projects, Lambada Roeun

Chulalongkorn University Theses and Dissertations (Chula ETD)

Knowledge sharing among construction project members is very crucial for improving project success and project performance. It can also reduce mistakes in the construction process. Project management has been growing more complicated, and project members need to learn best practice from others. Currently, knowledge sharing is not well performed yet; especially, few research studies have been focused on the relationship evaluation of supporting factors that affect knowledge sharing from different contexts in construction projects. Therefore, this study aims to develop the causal relationship model of supporting factors from psychological, individual, organizational, and technological factors that affect mediators - knowledge sharing …

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The Influences Of Granite Particle As A Mixing Material Of High-Strength Concrete, May Thazin Khine Jan 2018

The Influences Of Granite Particle As A Mixing Material Of High-Strength Concrete, May Thazin Khine

Chulalongkorn University Theses and Dissertations (Chula ETD)

The aim of this study is to investigate the effect of granite particle on the properties of high strength concrete by the partial substitution as fine aggregate. By grouping two categories as concrete with and without admixture is also performed in this experiment. The granite particle substitution percentage for concrete with admixture is set with 0%, 20%, 30%, 40% and 50% by weight of fine aggregate and 0%, 10%, 15% and 20% by weight of fine aggregate for concrete without admixture. The testing of concrete strength is conducted with compressive, split tensile, flexural, water permeability, and microstructure. The result shows …

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