The papers featured on this page are the culmination of student research regarding aspects of the Concrete Canoe. In many cases these projects were term projects for CE 334 - Mechanical Behavior of Materials. These papers are intended only for informational purposes and to assist in the development of future and current Concrete Canoe projects. USC ASCE is not responsible for the content or reliability contained in this research. For questions regarding these papers please contact uscasce@usc.edu
This report details the testing of four different size ranges of Poraver, a mixture of expanded glass granules, to determine the aggregate properties for use in concrete mix design.Specifically this testing sought to determine the specific gravity; absorption and gradiation of the Poraver samples for use in mix design for the USC ASCE Concrete Canoe.This experiment made use of standards from the American Society for Testing and Materials (ASTM Standards C29, C128 and C136).Our experimental data yielded specific gravities around 0.5 and absorption of approximately 6%.The errors in this data are largely believed to stem from deviation from the standard procedure specified in the ASTM Standards due to the availability of testing equipment. This report also includes gradiation curves and the Material Safety Data Sheet for Poraver as reference data for use by the USC ASCE Concrete Canoe teams.
Our objective for this project was to determine the optimum percentage by mass of recycled red glass to add into concrete mix by testing compressive and tensile strengths. We began with the last year’s design mix for our control. Our first glass amount (G1) was 11.7% of the mix and 42.5% of total aggregate. For G1 we substituted the same size poraver by mass as the amount of glass we added. Our second glass amount (G2) was 21.8% of the mix and 55.5% of total aggregate, and we added additional glass without taking out poraver to ensure it was more visible in the concrete. Compared to the control’s yield strength, G1 and G2 were both stronger in compressive tests. G1 had a stronger compressive strength than G2 on both day 7 and day 20. The tensile test revealed that red glass can lower the tensile strengths; however, because concrete canoe will add reinforcing for tensile strength, it is not as significant as compressive strength. We predict it would cost 180 dollars to add glass to the mix, which may or may not be feasible depending on this year’s budget.
Concrete admixtures have many uses in the construction industry, from allowing contractors to pour concrete in extremely cold and hot weather, or reducing waste by extending the workable lifetime of a batch of concrete, to chemically increasing the strength of concrete without affecting density. For the ASCE Concrete Canoe Team, admixtures could be the difference in having a low density, lightweight, yet workable concrete mix, or a problematic, crumbly and heavy mix – which has plagued the team for the past few years. The intricacies involved in choosing helpful admixtures, and the proper quantity to use, is what this research project will attempt to work out in order to assist this year’s Concrete Canoe Team in creating a better concrete mix. There are several different categories of admixtures, and hundreds of manufacturers. The following report discusses the types deemed advantageous to the Concrete Canoe Team, as well as the properties of these admixtures that make them an important addition to the concrete mix. The three admixtures chosen through extensive research were then tested in several different ways, both theoretical and experimental, to assess their effectiveness versus a control mix from last year’s team. The results of these tests determine whether or not the admixtures will be used in the Concrete Canoe Team’s concrete mix this year, and what tests would need to be performed next in order to find the exact amount of each to maximize effectiveness.
ASCE's concrete canoe team is researching effective mesh materials and spacing for the reinforcement in the concrete. Testing of various materials will be done by building multiple concrete specimens and failing them by loading with the Universal Testing Machine. By comparing the load carried by each specimen to possible situations in the concrete canoe, we can determine the most effective reinforcement material. "
In the consideration of this project we observed the flexural strength and serviceability of concrete that is reinforced with two different synthetic fibers: Polyvinyl Alcohol and Alkali Resistant Fiber Glass. In association with the American Society of Civil Engineers Concrete Canoe team, we utilized the pre-existing concrete mixture as a control mix. The concrete mix is a conglomerate of various density reducing agents specially designed for its light-weight and crack resistant properties. To further study the effects on cracking and workability of the fiber reinforced concrete mix, we applied dosages of two volumetric ratios of both synthetic fibers and tested them under flexural stress provided by the Universal Testing Machine. Upon testing we were able to verify an almost 300% increase in flexural strength and also a 210% increase in flexibility. Because of this added strength, a significant increase in ductility occurred which can be beneficial to the Concrete Canoe team. Our hypothetical assumptions were not only met but were surpassed greatly, thus introducing fiber reinforcement as not only a viable option for the ASCE Concrete Canoe team but would also benefit concrete structures and effectively replace steel reinforcement for thin slabs of concrete. For thick slabs of concrete it is not a cost effective means of reinforcement due to high cost.
University of Southern California – Viterbi School of Engineering
