Engineering Journal of Research and Development

STRUCTURAL STRENGTH INDEX FOR HIGHWAY PERFORMANCE EVALUATION

2024-07-16T13:39:35+07:00

This paper presents the analysis and evaluation of the structural performance of highway pavements using the Falling Weight Deflectometer (FWD) on major highways in Thailand. The study includes: (1) the relationship between the normalized deflection (d_o/d_{o, doh}) and pavement structural design parameters e.g. T_A, SN, and h_e according to Asphalt Institute (AI), American Association of State Highway and Transportation Officials (AASHTO), and Odemark's Method of Equivalent Thickness (MET), respectively, (2) the comparison between the modulus ratio (MR) obtained from the empirical approach by Wimsatt and that obtained from the Evaluation of Layer Moduli and Overlay Design (ELMOD), and (3) the comparison between the structural capacity index (SCI) obtained from the empirical approach by Rohde and that obtained from AASHTO. Results suggested that the normalized deflection required the maximum deflection (d_{o, DOH}) obtained from typical Department of Highways’ pavement structure. Conventional pavements were generally weaker than semi-rigid pavements. Both MR and SCI exhibited similar trends with respect to road engineering and maintenance management aspects. Higher MR and SCI values indicated stronger and safer pavements.

PROBLEMS THAT CAUSE HOME REPAIR AND RENOVATION CONTRACTORS TO ABANDON THEIR PROJECTS

2024-08-30T14:16:05+07:00

Home renovation and repair in Thailand has become more popular after the COVID-19 outbreak as people spend more time at home, resulting in a need to improve the space to make it more suitable for use. However, home renovation and repair projects often encounter the problem of contractors abandoning their projects, which affects both homeowners and contractors. This research aims to study the problems that cause contractors to abandon their projects in home renovation and repair, as well as to propose ways to prevent the problem. This research is qualitative research using a data collection method by interviewing the opinions of twelve contractors/construction business owners or engineers who have three years or more experience in home renovation and repair and have been responsible for projects worth more than one hundred fifty thousand baht. The researcher checked the validity of the question set by analyzing the consistency index. Then, the triangulation method was used to check the consistency of the data. In addition, the content analysis technique was used until the data was saturated to ensure that the obtained data was consistent with the objectives of the research. The results of the research found that the problems from the scope of work group, the financial problem group, and the quality of work group and the group of human resource problems covers up to 82% of the problems. If contractors manage to solve and prevent problems that may occur in these 4 groups, it will help reduce the chances of job abandonment and increase work efficiency effectively.

THE ANALYSIS OF ROAD ACCIDENT COMPONENT’ S FACTORS FOR THE FATALITY CASES: THE CASE STUDIES OF CHONBURI’ S PRICIPAL URBAN AREAS

2024-09-05T16:44:15+07:00

บทความนี้มีวัตถุประสงค์ เพื่อศึกษาปัจจัยองค์ประกอบการเกิดอุบัติเหตุทางถนนในกรณีที่มีผู้เสียชีวิตในพื้นที่เขตเมืองหลักจังหวัดชลบุรี ประกอบด้วย เมืองชลบุรี ศรีราชาและบางละมุง กลุ่มตัวอย่าง ทำการเลือกแบบเจาะจง (Purposive sampling) โดยคัดเลือกเฉพาะกรณีที่มีผู้เสียชีวิต จำนวน 1,016 ตัวอย่าง จากรายงานการเกิดอุบัติเหตุทางถนนของตำรวจภูธรภาค 2 จังหวัดชลบุรี ทำการวิเคราะห์ข้อมูลด้วยแบบจำลองสมการเชิงโครงสร้าง (Structural Equation Modeling, SEM) ผลการศึกษา พบว่า ประเภทพื้นทาง จำนวนช่องจราจร ตำแหน่งบนช่วงถนน และช่องจราจรที่เกิดเหตุ มีอิทธิพลทางตรงต่อปัจจัยที่เกี่ยวข้องกับถนน อย่างมีนัยสำคัญทางสถิติที่ระดับ .05 ประเภทยานพาหนะ และอายุ มีอิทธิพลทางตรงต่อความรุนแรงของอุบัติเหตุ อย่างมีนัยสำคัญทางสถิติที่ระดับ .05 โดยแบบจำลองสมการเชิงโครงสร้างของอิทธิพลที่ส่งผลต่อความรุนแรงของอุบัติเหตุในพื้นที่เขตเมืองหลักจังหวัดชลบุรี มีความสอดคล้องกลมกลืนกับข้อมูลเชิงประจักษ์ (p = .11, CMIN/DF = 1.29, GFI = .99, AGFI = .99, CFI= .97, RMR = .05, RMSEA = .02)

SIMULATION ANALYSIS OF THE REINFORCED EARTHQUAKE RESISTANCE OF RC BUILDING STRUCTURE MODEL WITH GLASS FIBER REINFORCED POLYMER USING BRACED FRAME SYSTEM

2024-09-21T11:08:54+07:00

This research aimed to study simulation analysis of the reinforced earthquake resistance of RC building structure model with glass fiber reinforced polymer using braced frame system. The size of reinforced concrete rigid frame used in the study was a 4000 mm in width and 3000 mm in height to simulate the strengthened behavior with glass fiber reinforced polymer by using braced frame system in bracing consisted of 4 types: X-braced frame, V-braced frame, Inverted V-braced frame, and Diagonal braced frame. The performance of the reinforced concrete rigid frame was evaluated using non-linear statics. The study results were found that: The X-braced bracing model provided the highest base strength compared to V-braced, Inverted V-braced and Diagonal braced model. The increased cross-sectional area ratio of the materials in bracing reinforced concrete rigid frame did not affect the increased strength of reinforced concrete rigid frame. Therefore, reinforced concrete materials in cross-section using reinforced materials with the lowest cross-section were sufficient to resist earthquake force. When comparing to deformed bar, the use of glass fiber reinforced polymer in cross-section can be used to replace deformed bar effectively.

STRENGTH AND WATER ABSORPTION PROPERTIES OF UNFIRED BRICKS CONTAINING SUGAR CANE BAGASSE ASH

2024-09-13T15:55:23+07:00

Bricks have been a widely utilized material in construction, though their production involves a firing process lasting between 7 and 15 days, which causes air pollution. This research had developed unfired bricks mixed with sugar cane bagasse ash to reduce environmental impacts and utilize biomass materials. The cement - soil ratio is 1:6 and finely ground bagasse ash replaces cement at 0, 10, 20, 30, 40, and 50 percent by weight. These mixtures were pressed into blocks, cured, and subjected to testing for compressive strength at 7, 14, 28, 60, and 90 days, water absorption and modulus of rupture at 28 days. The study found that the compressive strength at 7, 14, 28, and 60 days decreased as the amount of bagasse ash increased. Notably, at 90 days, the mixture with 10% bagasse ash substitution exhibited the highest compressive strength. An increase in bagasse ash content also led to a decreased modulus of rupture and higher water absorption. The recommended mixture is one that uses bagasse ash to replace 30% of cement, which had a compressive strength of 60 days or more and water absorption that passes the TIS 77-2565 criteria for quality bricks of grades C. Additionally, plaster applied to these unfired bricks demonstrated good adhesion during construction and plastering tests.

OPTIMIZING MAP PROJECTIONS FOR EQUILIBRIUM AND MINIMAL DISTORTION IN PROVINCIAL CONSTRUCTION PROJECTS

2024-10-08T21:49:35+07:00

The Universal Transverse Mercator (UTM) projection is widely used in design and construction projects in Thailand. However, in some areas, it may introduce linear distortions of up to 965 ppm. Therefore, the linear distortion caused by the UTM projection is considered a significant systematic error. This study investigates the design of Low Distortion Projections (LDP) at the provincial level, including Transverse Mercator (TM), Lambert Conformal Conic Projection (LCC), and Oblique Mercator (OMC). The research highlights the importance of "urban areas," where construction frequently occurs. These areas often have terrain elevations higher or lower than the average topographic surface, necessitating the development of a provincial LDP with a Combined Scale Factor (CSF) between -20 ppm and +20 ppm, covering over 80% of urban areas.Furthermore, an optimal balance for construction project LDPs is sought, with CSF values ranging between -10 ppm and +10 ppm.Using Phayao Province as a case study, specifically the Denchai - Chiang Rai - Chiang Khong railway project, Contract 2 (Ngao - Chiang Rai section), it was found that the Transverse Mercator LDP was the most suitable. This projection resulted in a provincial CSF range of -18 to +17 ppm and a project-specific CSF range of -8 to +8 ppm. Horizontal and vertical distortions were also analyzed using LDP parameters from control points within the project. The results revealed horizontal and vertical deviations ranging from -6 to +6 millimeters, demonstrating that a combined scale factor was unnecessary in practice. Selecting an appropriate LDP can significantly reduce errors in design and construction caused by map distortions. It is anticipated that Low Distortion Projections will play a more prominent role in Thailand's construction industry in the future.

APPLICATION OF GEOINFORMATICS AND REMOTE SENSING IN URBAN EXPANSION PREDICTION MODELING FOR COMPARATIVE URBAN ROAD NETWORK PLANNING: A CASE STUDY OF KHON KAEN CITY

2024-10-29T15:25:32+07:00

The objective of this research is to develop a predictive model for the urban expansion of Khon Kaen city, aimed at supporting analysis and comparison with maps produced from the prioritization of urban road networks included in the urban road network development plan by the Department of Rural Roads. This research integrates urban expansion prediction with three key factors: (1) land use change, (2) road networks, and (3) Digital Elevation Model (DEM) data. The prediction results are evaluated alongside urban road network development data to confirm the suitability of the maps included in the plan. The study area focuses on Khon Kaen Municipality in Khon Kaen Province as a case study. This research employs Landsat satellite images (1999–2019) and Google Maps data to construct a land use change model from 2024 to 2049. Additionally, artificial neural networks are applied to predict future land use trends. When comparing the 2024 simulation with actual conditions, the Kno, Klocation, and Kquantity indices range between 0.6 and 0.8, indicating an acceptable level of accuracy. The model is subsequently used to predict urban expansion and land use for the years 2024, 2029, 2034, 2039, 2044, and 2049. The research findings confirm the alignment of the proposed road network improvements, demonstrating the model's utility in supporting strategic urban planning.

ESTABLISHING CRITERIA FOR MACHINERY APPRAISAL USING MARKET APPROACH

2024-06-14T21:01:46+07:00

This research aimed to create criteria for machine price evaluation using the market approach. The research started with an in-depth review of relevant criteria from professionals. The next stage, the Analytic Hierarchy Process (AHP) was to create an analytical hierarchical diagram for prioritizing criteria, consisting of 6 main and 15 sub-criteria. A vertical milling machine was selected as a case. It was found that the top three important criteria were machine condition, machine efficiency, and maintenance with weights of 32.03%, 31.42%, and 13.38, respectively, the top three important sub-criteria were availability, machine integrity, and accuracy/precision, with weights of 18.28%, 14.44%, and 14.31%, respectively. After that, the Delphi technique was used to determine the rating level for each criterion. Consequently, when evaluating the value of a vertical milling machine, it was found that the difference in the value of the vertical milling machine of each appraiser could be reduced by 83%.