Civil Engineering Commons^™

Development Of A Structured Concrete Thermocline Thermal Energy Storage System, Bradley M. Brown

Graduate Theses and Dissertations

The past couple of decades have shown a concern when considering the way the world obtains its power. The focus has been switching from fossil fuels that have been used for hundreds of years to renewable energy sources, such as the sun. Solar energy is readily and infinitely available for harnessing. One problem with solar energy, though, is its inability to be used during the night time and during cloud covered weather. A solution to this problem is the use of energy storage mechanisms. For solar plants that use solar thermal energy (concentrating solar power plants), thermal energy storage (TES) …

Investigation Into The Role Of Airfield Pavement Deicer In Concrete Pavement Deterioration, David Wingard

All Dissertations

Premature deterioration of concrete due to materials-related distresses has been observed with increased frequency in airfield pavements across the United States in the past two decades. The use of a new breed of deicing chemicals based on alkali-acetates and alkali-formates, starting in the early 1990s, has been suspected to be one of the significant reasons for the increase in the observed deterioration. Previous laboratory-based studies have found that the early-age deterioration in concrete is associated with exposure to deicers causing acceleration of the Alkali Silica Reaction (ASR) deterioration mechanism and consequent failure. However, no systematic forensic studies on the impact …

Retrofit Solutions For Sealed Pervious Concrete Pavements, Gregory Bunting

All Theses

The goal of this research was to design, implement, and evaluate several retrofit solutions for sealed pervious concrete. Properly functioning pervious concrete pavements allow water to drain through the structure, eliminating the need for traditional drainage infrastructure. A recent study of South Carolina porous pavements (Putman 2010) revealed that some pervious concrete pavements are not properly draining, either because of sealing at the surface. Sealed pavements are generally a result of construction processes, and sealed pavements cannot be fixed with sediment removal techniques such as vacuuming and pressure washing. This study investigates a technique to increase infiltration of sealed pervious …

Comparison Of Two Methods For The Assessment Of Chloride Ion Penetration In Concrete: A Field Study, Eric William Ryan

Masters Theses

The currently accepted method for assessing the resistance of concrete to penetration of chloride ions is ASTM C1202, commonly known as the “Rapid Chloride Permeability (RCP) Test.” The test is time-consuming, laborious, has rather high variability, and, is to a degree, user sensitive, making it problematic for inclusion in a performance-based specification. A potential alternative to the RCP test is the “Surface Resistivity (SR) Test”, a method which is dramatically easier, faster, and has less variability than the RCP test. The research reported herein was directed toward determining a correlation between RCP and SR test measurements for Tennessee bridge deck …

Piedras Blancas Light Station Vista Point Improvement Plan, Larissa Heeren, Reuben Juster, Annamarie Usher, John Rossi, Nick Mitchell

Mechanical Engineering

Piedras Blancas Light station Improvement Involved the design of two separate parking lot/vista point plans as well as the creation of a concrete Iron Ranger located near the gift shop on site.

Gis Based Pavement Maintenance: A Systematic Approach, Robert J. Kmetz

Purdue Polytechnic Directed Projects

Abstract

According to 2008 Federal Highway Administration (FHWA) statistics, there are 2,734,102 miles of paved public roads in the United Sates, with an additional 1,324,245 miles of unpaved public roads. Road conditions deteriorate with time as the result of weather effects, deicing salts, and vehicle loads. The most common pavement distress includes cracking, rutting, and potholes. These pavement defects must be repaired to restore the pavement to a satisfactory service level for road users. According to the FHWA, in 2006 approximately $54.2 billion dollars was spent on maintenance and expansion, just on U.S. highways alone.

Routine maintenance is a cost …

Strength Properties Of Hybrid Nylon-Steel And Polypropylene-Steel Fibre-Reinforced High Strength Concrete At Low Volume Fraction, Hilmi Mahmud

Hilmi Mahmud

The strength properties of hybrid nylon-steel fibre-reinforced concrete were investigated in comparison to that of polypropylene-steel fibre-reinforced concrete, at the same volume fraction (0.5%). The content of the high performance macro structure steel fibres is at 0.4% volume fraction, and the content of micro nylon and polypropylene-fibres is at 0.1% volume fraction. The experimental results show that the compressive strength and splitting tensile strengths and modulus of rupture (MOR) properties of the nylon-steel fibre concrete improved by 3.2, 8.3 and 10.2%, respectively, over those of the polypropylene-steel fibre concrete. On the impact resistance, the first-crack and failure strengths, and the …

Improved Joining Method For Segmental Prestressed Structures, Ralph Warren Jensen

Open Access Theses & Dissertations

This dissertation addresses the need for more robust and materially efficient structures, specifically structures that absorb higher levels of energy, can self-erect and which have variable reaction capabilities. These structures can take much higher levels of strain and loading compared to current technologies in reinforced concrete and carbon fiber composites. These structures are made using a novel method of joining segmental elements. A great advantage with this segmental structural system is it's survivability under overloaded conditions. During an impact, or concentrated pressure load, the structure will wrap around the impact zone thereby widely distributing the contact stresses. This function or …

A New Method Of Producing High Strength Oil Palm Shell Lightweight Concrete, Zamin Jumaat

Zamin Jumaat

This paper presents a new method to produce high strength lightweight aggregate concrete (HSLWAC) using an agricultural solid waste, namely oil palm shell (OPS). This method is based on crushing large old OPS. Crushed OPS are hard and have a strong physical bond with hydrated cement paste. The 28 and 56 days compressive strength achieved in this study were about 53 and 56 MPa, respectively. Furthermore, it was observed that it was possible to produce grade 30 OPS concrete without the addition of any cementitious materials. Compared to previous studies, significantly lower cement content was used to produce this grade …