Civil and Environmental Engineering Commons^™

Indirect Evaporative Cooling Potential In Air-Water Systems In Temperate Climates, Ben Costelloe, Donal Finn

Articles

Recent developments have prompted a review of evaporative cooling technology as an effective means of cooling modern deep plan buildings. Prominent among these developments is the success of high temperature sensible cooling systems, particularly, chilled ceilings, which require a supply of cooling water at 14–18 °C. Crucial to the success of evaporative cooling technology, as a significant means of cooling in modern applications, is the ability to generate cooling water, in an indirect circuit, at a temperature which closely approaches the ambient adiabatic saturation temperature (AST) or wet bulb temperature (WBT). Recent experimental research has demonstrated that it is technically …

Bs News

Building Services Engineering

No abstract provided.

Bs News

Building Services Engineering

No abstract provided.

Strengthening Of Short Shear Span Reinforced Concrete T Joists With Fiber-Reinforced Plasic Composites, Francesco Micelli, Raghu H. Annaiah, Antonio Nanni

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In this work, the results of an experimental study conducted in a 1964-vintage building are presented. Twelve reinforced concrete (RC) T-joists strengthened with fiber-reinforced plastic (FRP) composites were loaded until failure in a short shear span configuration. Different strengthening schemes, including different FRP materials and a new FRP anchorage system, were adopted in order to compare the performance of the different installations. Carbon FRP and aramid FRP sheets in an epoxy matrix were bonded to the RC joists using the wet layup technique. All of the joists were loaded close to one end support and showed similar cracking patterns at …

Strengthening And Load Testing Of Three Bridges In Boone County, Missouri, S. Schiebel, R. Parretti, Antonio Nanni, M. Huck

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Three bridges in Boone County, Missouri - Brown School Road, Coats Lane, and Creasy Springs Bridges - were selected for strengthening with carbon-fiber-reinforced polymer laminates in both shear and flexure. The objective of the rehabilitation program was to remove the 15-ton load posting that had been imposed on each of the bridges. To verify the results of the upgrade, load tests were performed before and after strengthening on two of the bridges - Brown School Road and Coats Lane Bridges. This paper presents the procedures followed in the design, installation, and load testing of the bridges. A recommendation regarding the …

Review Of Stabilization Of Clays And Expansive Soils In Pavements And Lightly Loaded Structures - History, Practice, And Future, Thomas M. Petry, Dallas N. Little

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Expansive clay soils-those that change significantly in volume with changes in water content-are the cause of distortions to structures that cost taxpayers several billion dollars annually in the United States. Much has been learned about their behavior over the past 60 years, and relatively successful methods have been developed to modify and stabilize them. This paper reviews some of the key advances developed over the past 60 years in improving our understanding of the nature and methods of modifying and stabilizing expansive clay soils. The state of the practice in stabilization is presented, and practical and research needs to help …

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Building Services Engineering

No abstract provided.

Bs News

Building Services Engineering

No abstract provided.

Evaluation And Carbon Fiber Reinforced Polymer Strengthening Of Existing Garage: Case Study, Milan Vatovec, Paul L. Kelley, Tarek Alkhrdaji, Antonio Nanni

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The concrete-repair fiber reinforced polymer technology emerged in the United States during the past 10 years. Since 1995, carbon fiber reinforced polymer (CFRP) has been applied to strengthen concrete decks of a troubled posttensioned garage in Atlanta. During the construction of the garage, design deficiencies were found. A remedial repair, involving heavily reinforced, 7.6 cm (3 in.) thick Gunite (Shotcrete) beams, applied to the underside of the slab between drop panels in the east-west (E-W) direction, was developed in 1984. Since then, delamination of Gunite beams and other structural problems repeatedly occurred. Epoxy injection and other limited repairs were done …

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Building Services Engineering

No abstract provided.

Strength And Modulus Degradation Of Carbon Fiber-Reinforced Polymer Laminates From Fiber Misalignment, Xinbao Yang, Antonio Nanni, Stephen B. Haug, Chung Leung Sun

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Fiber-reinforced polymer (FRP) laminates are being used as external reinforcement for strengthening concrete members. The performance of unidirectional FRP laminates is highly dependent on fiber orientation with respect to applied load direction. In the case of fabrication by manual layup, it is possible to have fiber plies installed with improper orientation. In this project, the degradation of strength and modulus of carbon FRP laminates from fiber misalignment was investigated experimentally using tensile coupons. The specimens consisted of one and two plies of unidirectional carbon FRP impregnated with a two-component epoxy. The misalignment angles varied from 0 to 40° for the …

Formal Engineering Of Residential Buildings, Joseph E. Minor

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The performance of residential buildings during hurricanes is as important as the performance of other buildings. Buildings where people live and where they are likely to be when a hurricane strike must survive. If this premise is accepted, it follows that residential buildings should be afforded a degree of engineering attention that is commensurate with that given to industrial and commercial buildings. Building code authorities have not been blind to this need. In new procedures adopted for hurricane zones in the United States, common sizes and geometric shapes of timber and masonry residential buildings are formally engineered, and associated construction …

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Building Services Engineering

No abstract provided.

Bending Strength Of Hybrid Cold-Formed Steel Beams, Chi Ling Pan, Wei Wen Yu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

For the purpose of determining the load-carrying capacity of cold-formed steel structural members, the effective width approach has been used. Since most studies were limited only to the structural members, which were assembled from the same material in a given section, this investigation was concentrated on a study of structural strength and behavior of hybrid cold-formed steel beams subjected dynamic loads. An investigation was also conducted to study the validity of effective design width formulas for the design of these specimens. The materials used in this study were 25 AK and 50 SK sheet steels. A total of 72 spot-welded …

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Building Services Engineering

No abstract provided.

Rehabilitation Of Rectangular Simply Supported Rc Beams With Shear Deficiencies Using Cfrp Composites, Ahmed Khalifa, Antonio Nanni

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The present study examines the shear performance and modes of failure of rectangular simply supported reinforced concrete (RC) beams designed with shear deficiencies. These members were strengthened with externally bonded carbon fiber reinforced polymer (CFRP) sheets and evaluated in the laboratory. The experimental program consisted of twelve full-scale RC beams tested to fail in shear. The variables investigated within this program included steel stirrups, and the shear span-to-effective depth ratio, as well as amount and distribution of CFRP. The experimental results indicated that the contribution of externally bonded CFRP to the shear capacity was significant. The shear capacity was also …

Bs News

Building Services Engineering

No abstract provided.

Smart Growth And Land Acquisition Priorities, New England Environmental Finance Center

Land Conservation

It is well-known and generally accepted that all undeveloped land in New England cannot forever be protected from development; nor would this be a desirable goal, as continued economic development and population growth are near certainties. For these and other reasons, private land trusts and government agencies generally use explicit criteria to prioritize their land acquisition activities and prospects.

Much land protection in New England and elsewhere, however, has occurred without substantial attention to such land use needs as fostering the best locations for where people will live, businesses will locate, and infrastructure will be built to avoid degrading resources. …

Effect Of Ph And Gas-Phase Ozone Concentration On The Decolorization Of Common Textile Dyes, Craig D. Adams, Steven Gorg

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper presents the results of a laboratory study on the effect of pH (2, 5, and 9) and gas-phase ozone concentration (1, 7, and 11 wt. %) on the decolorization efficiency via ozonation for seven common textile dyes. Higher gas-phase ozone concentrations resulted in higher decolorization rates due to more rapid ozone transfer. Higher gas-phase ozone concentration, however, was also observed to have a positive, neutral, or negative effect on ozone dose requirements for different dyes. In general, greater ozone utilization efficiency was achieved at lower pH levels where direct ozone reactions predominate. It was observed that because ozonation …

Removal Of Antibiotics From Surface And Distilled Water In Conventional Water Treatment Processes, Craig D. Adams, Yang Wang, K. Loftin, M. Meyer

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Conventional drinking water treatment processes were evaluated under typical water treatment plant conditions to determine their effectiveness in the removal of seven common antibiotics: carbadox, sulfachlorpyridazine, sulfadimethoxine, sulfamerazine, sulfamethazine, sulfathiazole, and trimethoprim. Experiments were conducted using synthetic solutions prepared by spiking both distilled/ deionized water and Missouri River water with the studied compounds. Sorption on Calgon WPH powdered activated carbon, reverse osmosis, and oxidation with chlorine and ozone under typical plant conditions were all shown to be effective in removing the studied antibiotics. Conversely, coagulation/flocculation/sedimentation with alum and iron salts, excess lime/soda ash softening, ultraviolet irradiation at disinfection dosages, and …

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Building Services Engineering

No abstract provided.

Bs News

Building Services Engineering

No abstract provided.

Optimal Placement Of Dampers And Actuators Based On Stochastic Approach, Franklin Y. Cheng, Hongping Jiang, Xiaozhe Zhang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A general method is developed for optimal application of dampers and actuators by installing them at optimal location on seismic-resistant structures. The study includes development of a statistical criterion, formulation of a general optimization problem and establishment of a solution procedure. Numerical analysis of the seismic response in time-history of controlled structures is used to verify the proposed method for optimal device application and to demonstrate the effectiveness of seismic response control with optimal device location. This study shows that the proposed method for the optimal device application is simple and general, and that the optimally applied dampers and actuators …

Biological Fixed Film Systems, Mark W. Fitch, Ellen England

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

No abstract provided.

Behavior Of Screw Connections In Residential Construction, Roger A. Laboube, M. A. Sokol

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Self-drilling screws are the primary means of fastening cold-formed steel members in residential construction. Because the fabrication of connections is the most labor-intensive aspect of the construction process, a better understanding of the behavior of screw connections could lead to more optimum connection design. Therefore, studies have been performed at the University of Missouri-Rolla aimed at developing a better understanding of the behavior of single-shear connections using self-drilling screws in cold-formed steel construction. The study's focus was on design parameters typically employed in residential construction. Fastener patterns, screw spacing, stripped screws, and the number of screws in a connection was …

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Building Services Engineering

No abstract provided.

Smooth Static And Dynamic Indentation Of A Cantilever Beam, Minggang Zhou, William P. Schonberg

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The static and dynamic indentation of structural elements such as beams and plates continue to be intriguing problems, especially for scenarios where large area contacts are expected to occur. Standard methods of indentation analyses use a beam theory solution to obtain an overall load-displacement relationship and then a Hertzian contact solution to calculate local stresses under the indenter. However, these techniques are only applicable in a fairly limited class of problems: the stress distribution in the contact region will differ significantly from a Hertzian one when the contact length exceeds the thickness of the beam. The indentation models developed herein …

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Building Services Engineering

No abstract provided.

Practical Issues For The Application Of High-Performance Concrete To Highway Structures, John J. Myers, Yumin Yang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In recent years, the advantages of high-performance concrete (HPC) have been well documented. Among others, these advantages include enhanced design flexibility and improved durability performance that results in reduced maintenance costs and an increased service life. Despite these obvious benefits, the implementation of HPC has been very slow. This can be attributed to several factors including the uncertainty related to current design codes and a lack of familiarity of designers and contractors with practices and requirements for proper design and construction of high-performance concrete structures. This paper introduces and discusses several fundamental issues that affect the implementation of HPC and …

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Building Services Engineering

No abstract provided.