Cost overrun is prevalent in the construction industry. Usually, an owner sets a budget at the preliminary phase of a project which changes over time. Past studies are focused on analyzing the cost growth of design-bid-build projects during construction. Limited efforts have been made to analyze details of projects delivered with the Construction Manager General Contractor (CM/GC) method. This study tracks and analyzes the construction cost variation of a project from the conceptual phase to the design completion phase. The analysis is presented with a case study of a new stadium construction project. It identifies that the changes in the scope and design of the project due to the change in available budget were a major reason for variation in the cost estimates over time. Further, this study identifies a) trades with the highest variation in subcontractors’ bids, b) trades that were most overestimated, and c) trades that were most underestimated. The findings of this study is expected to aid owners, designers, and contractors of future projects in improving the preparation, planning, and estimating of future projects; reducing cost variation within trades; and optimizing the amount of contingency required to ensure the successful completion of similar projects.

Since 1976 public agencies in Oregon have been allowed to select construction contractors using a "qualification" based competition instead of the more typical lowest responsible bid or Design-Bid-Build (DBB) basis. Since 1985, at least 136 such selections, commonly known as CM/GC for Construction Manager/General Contractor, have been made. The results of this policy have not previously been analyzed. This research compares these selection methods, seeking to answer the following questions: Does the CMl/GC method result in projects that differ from DBB projects regarding cost and schedule control? Are CMl/GC projects more efficient than DBB projects, where efficiency is defined as the data envelopment analysis (DEA) technical efficiency score? Does efficiency depend on an interaction between project type and the selection method? How do project stakeholders evaluate the benefits and drawbacks of the two selection methods? How do projects compare when the only apparent difference between them is the selection method? To answer these questions, we identified 407 Oregon public building construction projects and obtained a variety of data, including cost and schedule results, for 215 jobs (111 CMl/GC and 104 DBB). We analyzed the data several ways, including statistical analysis, DEA, and various qualitative methods. Results: There was no statistically significant difference between the CMl/GC and DBB projects regarding cost and schedule control. The DEA technical efficiency scores showed that CMl/GC projects outperformed the DBB projects. There was no interaction effect between project type and selection method. Project stakeholders stated that reduction of risk is the principal benefit of using CMl/GC; however, architects and subcontractors are less enthusiastic than owners and general contractors. Data on two nearly identical projects indicated that the DBB project was less costly than the comparable CMlGC project and also incurred less cost growth; both projects were completed on time. To summarize, this research fails to find support for the current Oregon law that exempts certain projects from competitive bidding based on the presumption that CMl/GC will lead to substantial cost savings but does indicate that the CMl/GC projects may be better able to accommodate accelerated project schedules.

Zoning map of downtown Elizabethton, TN and the surrounding area. Legend includes notations of type of dwelling. Originally published in 1953 by the Elizabethton Planning Commission, the color portions were filled in by hand using colored pencil and correspond to the different zoning areas. It is unclear when the color was added. As you can see in the top left quarter of the map, this was before the creation of Sycamore Shoals State Park which was established in 1975 along the Watauga RIver and is located just northwest of downtown. Physical copy resides in the Government Information, Law and Maps Department of East Tennessee State University’s Sherrod Library. / https://dc.etsu.edu/rare-maps/1001/thumbnail.jpg

Zoning map for Johnson City, Tennessee created February 18, 2000 by Johnson City GIS. The guide to zoning districts can be found in a box on the lower left corner. The color coded key and additional information is included along the bottom. Arterial and collector streets are also denoted using empty versus solid circles. Physical copy resides with Johnson City, Geographic Information Systems Division. Scale - 1" = 2000' / https://dc.etsu.edu/rare-maps/1058/thumbnail.jpg

This design explores an alternative approach to New England home construction which emphasizes construction efficiency as well as ease of maintenance, renovation, and reconfiguration throughout the structure’s lifetime. The structure’s efficiency and flexibility is achieved by using the Bosch-Rexroth framing system and strategic placement of building systems. The reconfigurable structure paired with a changeable cladding system anticipates necessary seasonal and programmatic changes. The buildings systems are concentrated together for increased accessibility and serviceability. The design proposes a house that is inexpensive and easily maintained and adapted by the occupants throughout its lifetime.

This research compares the energy performance of a code-built residential building within the moist climate zone classification in Canada, Europe, and the Northeastern United States. The primary objectives are to reveal how specific differences in code requirements in similar climates influence a building’s energy profile, offer a means to quantify and evaluate the extent of energy savings as a result of each requirement, and provide a comparison of each location’s building culture and how this affects the standards in place. Using the building energy simulation tool, DesignBuilder EnergyPlus Simulation, a model single-family home was created and input energy code requirements for each location. An evaluation of each location’s building culture is examined through such factors as the training of building professionals, commonly used materials and products, energy reduction goals, and cultural attitudes. The results of this study point to the need for more advanced building practices, stricter code mandates, and higher performing products based on energy savings achieved from buildings built to different standards in equivalent climate zones. This has the potential to drive the development and use of better performing building materials and assemblies in the future.

The purpose of this study is to determine the value of a master's degree in construction management in southern Idaho. A telephone and Internet survey was employed to determine the value that members of the construction industry in southern Idaho place on construction management (CM) degrees, both graduate and undergraduate. The survey included 27 self-described general contractors who are members of The Associated General Contractors of America (AGC) in regions 3 and 4 in the state of Idaho. Regions three and four include Twin Falls, Idaho Falls, Pocatello, Ketchum, Burley and surrounding communities. Following the compilation of surveys, it was found that the group of participants 1) knew there was a bachelor's degree in CM; however, some didn't realize there was a master's degree in CM; 2) felt that education is sometimes over rated; 3) perceived no difference in hiring an undergraduate v. a graduate in terms of monetary value. There was a perceived value in a master's degree itself.

Wire Electric Discharge Machining (wire-EDM) is a non-traditional machining process. Controlled electric sparks are successively used to vaporize part of a workpiece along a programmed path in order to machine a desired part. Because there is no tool that comes in direct contact with the workpiece, it is possible to machine thin, delicate parts. This thesis was designed to observe and analyze the differences in cutting capabilities for a conventional wire-EDM machine when cutting thin-walled sections from five commonly used metals utilizing a variation of roughing and finishing passes. The five metals that were used in this study are: Aluminum 6061 T6, Yellow Brass SS360, 420 Stainless Steel, D2 Tool Steel at 25 to 30 RC, and D2 Tool Steel at 60 to 65 RC. The thin-walled sections were constrained on each end by the parent material to which they remained attached, and they ranged in thickness from 0.05 millimeters (0.002 inches) increasing incrementally by 0.05 millimeters (0.002 inches) until they reached a thickness of 0.30 millimeters (0.012 inches). A Sodick AQ325L wire-EDM machine was employed to perform the machining. It was observed that differences exist in the capabilities of cutting thin-walled sections from the five different metals. This could be both observed visually through inspection and statistically through the analysis of each data set obtained by measuring the resultant thickness of each section. It was also observed that differences exist for the same material while utilizing the variations of cutting parameters: a roughing with no finishing passes, a roughing with one finishing pass, and a roughing with three finishing passes. Thus both the material properties and the cutting parameters play a significant role in determining the capability of cutting thin-walled sections with a wire-EDM machine.

Polyvinyl Chloride, commonly known as PVC is a common and effective construction material. PVC is also one of the most common types of plastic. In 2008, global production and consumption of PVC was approximately 34.5 million tons. The construction industry is responsible for about 70% of the world's consumption of PVC. The largest construction use of PVC is for pipe and conduit. Modern construction, especially structures built for data services depend heavily upon PVC conduit for underground pathways to distribute electricity and data. PVC is also at the center of a fierce effort by environmental groups who would like to see it eliminated completely. If environmentalists are successful in their efforts to eliminate PVC; builders will be left without a material that is crucial for many applications. Seven alternative conduit materials have been identified as potential replacements for PVC electrical conduit. PVC electrical conduit is commonly used in commercial, industrial, and civil construction. This thesis undertook to study the four major electrical contractors in the state of Utah which employ more than one hundred electricians. Because major electrical contractors use large quantities of PVC conduit, electricians working for these contractors were surveyed to determine their preferences of alternative materials. A questionnaire was distributed and received 112 responses, which represent 6.5% of the total population. This study found that PVC was the most used, most preferred, easiest to install and was perceived as the least expensive conduit material. Polypropylene and High Density Polyethylene were rated next highest, but were also the least commonly used of the alternative materials. The other materials, which include: Nylon, Fiberglass, Fiberglass Reinforced Epoxy, Polyurethane Coated Steel, and Galvanized Steel were also examined. Many of the respondents expressed displeasure by the effort to eliminate PVC and the vast majority felt that green certification for construction did not justify elimination. These responses indicate that more needs to be done to introduce alternative conduit materials to users of PVC and educate them about the value of the alternatives. This study represents an important step in evaluating the value of PVC conduit and its alternatives.

Friction Bit Joining (FBJ) is a recently developed spot joining technology capable of joining dissimilar metals. A consumable bit cuts through the upper layer of metal to be joined, then friction welds to the lower layer. The bit then snaps off, leaving a flange. This research focuses on FBJ using DP980 or DP590 steel as the lower layer, AZ31 magnesium alloy as the top layer, and 4140 or 4130 steel as the bit material. In order to determine optimal settings for the magnesium/steel joints, experimentation was performed using a purpose-built computer controlled welding machine, varying factors such as rotational speeds, plunge speed, cutting and welding depths, and dwell times. It was determined that, when using 1.6 mm thick coupons, maximum joint strengths would be obtained at a 2.03 mm cutting depth, 3.30 mm welding depth, and 2500 RPM welding speed. At these levels, the weld is stronger than the magnesium alloy, resulting in failure in the AZ31 rather than in the FBJ joint in lap shear testing.