Structural Engineering Commons^™

Evaluating The Impact Of Bridge Deck Removal Method On The Performance Of Precast/Prestressed Concrete I-Girders, Shaddi Assad

Department of Construction Engineering and Management: Dissertations, Theses, and Student Research

Wide flange precast/prestressed concrete I-girders have been widely used by several State Departments of Transportation (DOTs) in the last two decades. These girders have many advantages over standard AASHTO I-girders. Their wide and thick bottom flange accommodates a large number of prestressing strands and their wide and thin top flange provides a shorter deck span, reduced girder weight, greater stability in construction, and adequate platform for workers. Despite these advantages, the wide and thin top flange might be disadvantageous when it comes to deck removal, as it is more susceptible to damage. Therefore there is a need to investigate the …

Effects Of Stirrups On Bond Behavior Between Concrete And Corroded Steel Bars, Hongwei Lin, Yuxi Zhao, Ming Sun

International Conference on Durability of Concrete Structures

Steel corrosion leads to the deterioration of bond between concrete and steel bars. The serviceability and ultimate strength of concrete elements within RC structures are hence affected. Many researchers have studied the bond behavior of corroded steel bars. However, very few studies have investigated the effects of confinements on the degradation of bond strength. The present paper proposed a new kind of beam specimen based on which the effects of stirrups on degradation of bond were investigated. The test results proved that stirrups can effectively increase the bond strength between concrete and corroded steel bars.

No Admixture, Sustainable, Self-Consolidating Grout, Craig V. Baltimore Dr

Craig V. Baltimore

ABSTRACT: The consolidation of grout in concrete masonry unit (CMU) walls is labor-intensive. Also, the grout’s Portland cement content has a high embodied energy demand – a non-sustainable characteristic. For the labor-intensive issue, chemical admixture self-consolidating grouts have been used in walls 12.67 ft. (3.86 m) tall, however the chemical additive can impose new limitations on the grout (non-robust characteristics). No admixture self-consolidating grout with high percentage Portland cement replacement have potential for robust and sustainable application.

This paper reports on the consolidation of no admixture self-consolidating grout made by substituting high percentages of Portland cement with Type-F fly ash …

Seismic Response Of A Tall Building To Recorded And Simulated Ground Motions, Nenad Bijelic, Ting Lin, Gregory Deierlein

Civil and Environmental Engineering Faculty Research and Publications

Seismological modeling technologies are advancing to the stage of enabling fundamental simulation of earthquake fault ruptures, which offer new opportunities to simulate extreme ground motions for collapse safety assessment and earthquake scenarios for community resilience studies. With the goal toward establishing the reliability of simulated ground motions for performance-based engineering, this paper examines the response of a 20-story concrete moment frame building analyzed by nonlinear dynamic analysis under corresponding sets of recorded and simulated ground motions. The simulated ground motions were obtained through a larger validation study via the Southern California Earthquake Center (SCEC) Broadband Platform (BBP) that simulates magnitude …

Behaviour Of Reinforced Concrete Conical Tanks Under Hydrostatic Loading, Tareq M. Azabi

Electronic Thesis and Dissertation Repository

Reinforced concrete conical tanks are used in municipalities and industrial applications as liquid containing vessels. Such tanks can be ground supported tanks or elevated on a supporting shaft. Although most design codes provide guidelines for rectangular and cylindrical tanks, no guidance is provided in such codes for conical tanks. Therefore, this thesis is motivated to study the behaviour and design of this type of tanks. In the current study, the accuracy of a design approach based on the provisions of Portland Cement Association (PCA-CCTWP) code for cylindrical tanks combined with an equivalent cylindrical approach provided by the American Water Works …

Making Bridges Outlast Rising Waters, Daniel Cox

TREC Project Briefs

During Hurricanes Ivan in 2004 and Katrina in 2005, at least 11 highway and railroad bridges along the U.S. Gulf Coast were damaged by wave forces. The spans of these bridges typically rested on bent column supports, and were attached to the supports by a variety of connection methods. Failure of these connections caused bridge spans to be washed away when the water rose high enough to lift them off. To build bridges that can withstand such forces, engineers must be able to estimate the effects the forces will have.

Investigator Daniel Cox of Oregon State University has conducted wave …

Testing And Analysis Of An Alternative Connection Method In Closed Panel Timber Frame Domestic Construction, Brendan Towey

Masters

Construction practices continue to evolve in tandem with the requirements for more energy efficient buildings, materials and construction methods. This steady and progressive move towards the development of the industry and its products comes, not in leaps and bounds, but in incremental advances across all areas of construction. The research detailed in this project is one such advancement. Timber frame construction has been in existence for centuries and its tried and tested methods have been utilised worldwide in both domestic and industrial building. In recent times, standard open panel timber frame construction has been enhanced by the development of closed …

Mechanical And Transport Properties Of Alkali-Activated Natural Pozzolans As Sustainable Binders, Brittany Radke

Calvert Undergraduate Research Awards

OPC production accounts for 5 to 7% of the global carbon dioxide (CO₂) emissions, contributing to global warming. The desire to reduce CO₂ emissions and produce more durable concrete has given impetus to search for new binders. It is suggested that alkali-activated natural pozzolans have the potential for use as a sustainable replacement for OPC in concrete.

The current study presented herein evaluated fresh, mechanical, and transport properties of alkali-activated natural pozzolan mortars containing various concentrations of sodium hydroxide solutions as an alkaline activator. To this aim, alkali-activated natural pozzolan mortars were made with concentrations of sodium …

Implementing Green Roofs On Movie Theaters And Shopping Centers: Business Cases In Profitable Sustainability, Ryan J. Miller

Pomona Senior Theses

This thesis presents the business case for installing green roofs on movie theaters and shopping centers. These businesses can then derive increased profits from the environmental benefits of reduced energy use and increased stormwater retention. After presenting the basic design and benefits of a green roof, the thesis develops stand-alone business plans for a movie theater and shopping center. The author finds that green roofs are a profitable sustainability solution for the commercial enterprise.