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Item Geostatistical Interpolation and Analyses of Washington State AADT Data from 2009 – 2016(North Dakota State University, 2019) Owaniyi, Kunle MeshachAnnual Average Daily Traffic (AADT) data in the transportation industry today is an important tool used in various fields such as highway planning, pavement design, traffic safety, transport operations, and policy-making/analyses. Systematic literature review was used to identify the current methods of estimating AADT and ranked. Ordinary linear kriging occurred most. Also, factors that influence the accuracy of AADT estimation methods as identified include geographical location and road type amongst others. In addition, further analysis was carried out to determine the most apposite kriging algorithm for AADT data. Three linear (universal, ordinary, and simple), three nonlinear (disjunctive, probability, and indicator) and bayesian (empirical bayesian) kriging methods were compared. Spherical and exponential models were employed as the experimental variograms to aid the spatial interpolation and cross-validation. Statistical measures of correctness (mean prediction and root-mean-square errors) were used to compare the kriging algorithms. Empirical bayesian with exponential model yielded the best result.Item Conceptual Cost Estimation Models for Bridge Projects(North Dakota State University, 2021) Essegbey, Adikie EsinamConceptual cost estimating is typically completed early in the project lifecycle when little design work has been completed. Because little information is known at this early stage, the estimate usually deviates substantially from the actual construction cost. Therefore, the objective of this research is to develop a conceptual cost estimate model for bridge infrastructure projects. In this study, a systematic literature review and meta-analysis of Mean Average Percentage Errors (MAPEs) of cost models was undertaken to identify the various cost estimation methods, the input variables that have adopted in the development of models and determine the impact of cost estimation method on the accuracy of cost prediction. The research study utilized regression analysis, decision tree and random forest methods for cost prediction of Wisconsin bridges. A comparison of the three models that were developed revealed that random forest cost estimation method yielded better cost prediction.Item Studying Window Energy Performance Using Thermal Camera(North Dakota State University, 2020) Akbari, SevdaWindows, which are responsible for 45% of overall heat loss, play a major role in a building’s energy performance. Therefore, it is critical to measure window energy performance for existing buildings. This study aimed to evaluate the energy performance of windows to determine if replacement of windows is necessary. The evaluation was based on window location, height, orientation, and weather condition in a high-rise residential building. A thermal camera was used for measurements and statistical analyses were performed for measured data. Analysis results showed different performance of each side and floor of the building with a significant difference at the 0.05 level due to various temperatures, wind speeds, and directions. This study suggests using more efficient windows on upper floors, particularly from the fourth floor and above is beneficial as well as considering dominant wind speed and direction for the best configuration of window design.Item Contractor Prequalification Practices in Bangladesh(North Dakota State University, 2013) Molla, Mohammad Mofigul IslamLike many developing economies, the construction industry in Bangladesh is vital to its economic development and growth. However, the Bangladeshi construction industry is plagued by unethical practices, sub-standard construction work, and the inability of local contractors to partake in internationally funded (lucrative) contracts (as general contractors). A contractor prequalification process is proposed to address the problems facing the industry. In this work, an extensive literature review was used in combination with research surveys, statistical analyses of the literature and survey results, and the analytical hierarchy process to develop sets of factors and criteria pertinent to contractor prequalification/selection. A five-level framework involving regulatory verification, project-specific validation, performance evaluation, state-of-the-art best practices, and capacity assessment was developed to address the problem. This research developed innovative practices that could be used for the prequalification of contractors in Bangladesh and a method for implementing a recommended system for evaluating and prequalifying contractors.Item Insulation in Windows Using Resin & Aerogel Mixture(North Dakota State University, 2019) Pujar, Priyanka MallikarjunInsulation materials are essential in building construction; this study proposed to use one such material called silica aerogel, which is known for its excellent thermal properties, and a UV acrylate resin that has been formulated to mix with the aerogel. In this experiment, existing methods of aerogel insulation are discussed and a novel method is investigated. U- value and R- values were obtained by LHICD (i.e., Laser Heating Infrared Camera Detecting method), and K - values were calculated using an equation for 0%, 22.5% and 45% volume of aerogel. The study suggests that using aerogel and resin coating on windows could help to improve the insulating properties of windows. i.e., low thermal conductivity and high thermal resistivity. The results obtained demonstrate that as we increase the percentage volume of aerogel in window coating, the window’s thermal conductivity decreases, and the thermal resistance increases.Item Identification of Factors Contributing to Traffic Fatalities in the United States(North Dakota State University, 2015) Kaur, DharminderTraffic accidents not only cause injuries and deaths but also result in significant property and economic losses. With annual 40,000 lives lost in United States and $80 billion in economic losses, research in minimizing accidents is a major priority. This research identified and ranked factors that reduce traffic fatalities and determined their relative importance. A total of 93 factors were identified and ranked into seven major categories through a systematic literature review. A questionnaire was sent to the State Departments of Transportation, and the responses were coded and analyzed using a relative importance index, rankings and percentages. The systematic literature review and survey results indicated that agencies should direct resources toward the highest-ranking factors to achieve better safety performance. Efforts should be made to improve infrastructure and influence road-user behavior towards safer habits. Laws and policies are vital to maintaining good road-user behavior, which could leads to lower traffic fatalities.Item Comparing Cooling of Warm Mix to Hot Mix Asphalts(North Dakota State University, 2015) Ahmed, Syed OwaisWarm mix asphalt (WMA) is increasingly being tried in highway paving in the United States. Apart from environmental benefits, WMA is being considered useful in projects involving long haul distances and late season paving operations due to its material characteristics and the rate of cooling during field compaction. This thesis investigates whether WMA cools at a slower rate than hot mix asphalt (HMA) to offer more compaction time. Following an indirect investigative approach, comparative analysis of field observations with software predicted values for two paving projects was carried out. The results indicated that some types of WMA cool at a slower rate than HMA and would allow a longer period of compaction time to achieve the same density as HMA. The findings presented here can be informative to the asphalt paving industry in considering WMA for use in long haul, nighttime, and late season paving.Item Conceptual Cost Estimation of Highway Bid Items Using Geostatistical Interpolation(North Dakota State University, 2021) Awuku, BrightChallenges associated with ensuring the accuracy and reliability of cost estimation of highway bid items, especially during the conceptual phase of a project, are of significant interest to state highway agencies. Even with the existing research undertaken on the subject, the problem of inaccurate estimation of highway bid items still exists. A systematic literature review was performed to determine research trends, identify, categorize the factors influencing highway unit prices, and assess the performance of conceptual cost prediction models. This research proposes a geographic information system (GIS)–based methodology that leverages vast historical bid data for unit-price estimation and the robust GIS capabilities with consideration of the effects of project-specific location and variations due to cost escalation on different bid items. A comparison of the three spatial interpolation techniques operationalized in this research revealed that disjunctive and empirical Bayesian kriging models led to more accurate cost prediction than ordinary kriging algorithms.Item Development of Sustainable Construction Material From Fly Ash C(North Dakota State University, 2016) Shrestha, MonishaEnvironmental issues caused by the production of Portland cement have necessitated its replacement by waste materials like fly ash which has been proven to be quite beneficial environmentally and economically. Therefore, this research project was focused on the development of sustainable construction materials using 100% of high-calcium fly ash with KOH based alkaline solution. Experimental work was conducted to determine concrete properties like compressive strength, flexural strength, setting time, and slump. In the phase I of the research, CNTs were also used to study its effect on geopolymer mortar. The results derived from the experiments show that mortar and concrete made with 100% fly ash C needs alkaline solution to reach properties established by Portland cement concrete. However increased amount of KOH generates heat making the concrete to set faster without forming a proper bond. Furthermore, the addition of CNTs makes the mortar sturdier than the one without CNT.Item Numerical Simulation and Structural Optimization of Composite Rigid Frame Bridge(North Dakota State University, 2017) Xie, YanmeiA composite rigid frame bridge replaces a certain portion of the concrete middle span of a bridge with a section of the steel girder. While the steel span improves the bending moment distribution of the rigid frame structure, it increases the stress level of certain cross-sections of the girder. There is little research reporting the effects of the addition of the steel span on the layout and structural design. This research studies the influence of the steel span on the structural behavior of the rigid frame bridge and conducts the structural optimization regarding the steel span ratio, curve order of the girder’s bottom line, and height-to-span ratio using the bending strain energy as the objective function. Finally, this study develops the computer program for structural analysis of composite rigid frame bridge structure using MATLAB, which can be used for advanced structural optimization.