http://www.archive.org/details/designofcoalyard00comp Thesis (B.S.)--Armour Institute of Technology; Includes folded leaves in back pocket;... Show morehttp://www.archive.org/details/designofcoalyard00comp Thesis (B.S.)--Armour Institute of Technology; Includes folded leaves in back pocket; Bibliography: leaf 63 Show less
The bond interface line of concrete overlays and enlargements has been the focus of engineers, contractors, and manufacturers for many years.... Show moreThe bond interface line of concrete overlays and enlargements has been the focus of engineers, contractors, and manufacturers for many years. Many products and procedures have been developed to help the contractor and engineering community achieve the highest bond strength of the repair material to the host material, or substrate, to provide a quality, long-lasting repair. It is well known that the difference between a successful overlay or enlargement and one that fails can be directly linked to the preparation of the bonding surface. The objective of this study is to compare what concrete removal techniques, or surface preparations, in conjunction with bonding conditions and agents have on achieving the best direct tensile and guillotine test results. A unique step of this research is to use an overlay material with the same mix design as the base slab. Most overlay materials are stronger and do not use the same coarse aggregate and cement. By having the substrate and the overlay concrete the same material, a true test of the bond can be accomplished as the core samples should fail in both the substrate and overlay. This study consisted of four concrete slabs that were poured and allowed to naturally cure for a full year. Afterwards, each slab used a different method to remove up to two and one-half inches of the substrate concrete to prepare for the overlay. Removal methods used were hydrodemolition, pneumatic impact hammers, abrasive blasting and a control slab that consisted of a light broom finish. Each panel was then divided into four sections and a different surface condition or bonding agent was applied to the substrate just prior to the placement of the overlay. The surface conditions and agents used were dry, surface-saturated dry (SSD), sand/cement slurry and an epoxy and cementitious material. After the overlay was placed, the overlaid test panels were allowed to remain in place and naturally cure for an additional year before test samples were taken. Results supported that any impact blow force to the surface yielded the worst results by almost 50% for both direct tensile and guillotine tests. Even a change in bonding agents could not overcome the damage to the surface of the base slab. These results support years of similar test reporting. There was no increase in test results using a bonding agent on any of the prepared slabs. The results were similar, and in some cases, less than a surface that was dry or SSD. The highest and most consistent results came from the slab that was either dry or SSD. Results indicate that a dry surface that is prepared with either abrasive blasting or hydrodemolition may yield the most consistent results as all other bonding conditions and agents are subject to difficulty in measuring the application accurately and can be highly susceptible to evaporation rates and variations in multiple mixing operations. A well prepared, clean, dry surface will yield the greatest and most consistent failure results and is the easiest to monitor and duplicate in field conditions. M.S. in Civil Engineering, May 2017 Show less
http://www.archive.org/details/effectofaddingsp00hall Thesis (B.S.)--Armour Institute of Technology, 1914 Bibliography: leaf 22 B.S. in Civil... Show morehttp://www.archive.org/details/effectofaddingsp00hall Thesis (B.S.)--Armour Institute of Technology, 1914 Bibliography: leaf 22 B.S. in Civil Engineering, 1914 Show less
Accurate characterization of building characteristics that influence indoor air quality (IAQ), thermal comfort, and energy consumption in... Show moreAccurate characterization of building characteristics that influence indoor air quality (IAQ), thermal comfort, and energy consumption in buildings is often limited to the use of proprietary hardware and software, which can adversely affect both functionality and costs. In response, the Open Source Building Science Sensors (OSBSS) project was launched to design and develop a network of inexpensive open source devices based on the Arduino platform for measuring and recording long-term indoor environmental and building operational data. The project includes a variety of sensors and dataloggers designed to assess energy, comfort, and air quality in buildings, including air and surface temperatures, air relative humidity, surface water activity, human occupancy and activity, light intensity, CO2, and a generic datalogger that can log data from other sensors such as HVAC system pressure sensors for determining system airflow rates or runtimes. The development, calibration, and performance of the sensor network is being documented in its entirety and made available freely online along with detailed tutorials designed to allow other researchers to incorporate the sensors in both ongoing and future investigations of energy, air quality, and comfort in the built environment. The OSBSS network of devices will ultimately allow for more flexibility in synchronizing a large number of measurements with high spatial and temporal resolution in a more cost effective manner for use in research projects and building automation and control. M.S. in Civil, Architectural and Environmental Engineering, May 2015 Show less