Thesis (M.S.)--University of Texas at El Paso, 2008. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.

Thesis (M.S.)--University of Texas at El Paso, 2009. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.

Thesis (M.S.)--Brigham Young University. Dept. of Civil and Environmental Engineering, 2006. / Includes bibliographical references (p. 39-40).

Thesis (M.S.)--Brigham Young University. Dept. of Civil and Environmental Engineering, 2005. / Includes bibliographical references (p. 61-63).

Not available / text

Thesis (M.S.)--Brigham Young University. Dept. of Civil and Environmental Engineering, 2006. / Includes bibliographical references (p. 43-46).

No description available.

Asphalt concrete pavement is subjected to several damaging actions from traffic loads, water (from precipitation and/or groundwater sources), and temperature. The durability of the asphalt-aggregate mixture, its ability to withstand these damaging actions for long periods, is a very important engineering property. While the durability of the asphalt-aggregates mixture depends on several factors such as the mixture's properties, construction methods, traffic loads and environmental conditions, they have to be evaluated to predict their field performance. Based on mixture evaluations, the mixtures that fail the test would have to be modified by additives or by changing the materials. The first objective of this thesis was to evaluate asphalt-aggregate mixtures for water damage using the Environmental Conditioning System (ECS), and rank the asphalt and aggregate types based on water sensitivity. The second objective was to relate the ECS ranking of the asphalt and aggregate types to Oregon State University (OSU) and University of Nottingham, UK (SWK/UN) wheel tracking test results, and to Net Adsorption Test (NAT) results. The third objective was to evaluate open-graded mixtures and rubber modified mixtures for water sensitivity using the ECS. The ECS test results indicate that performance ranking of mixtures by asphalt type or aggregate type alone cannot be made for the ECS test results due to the significant interaction between asphalt and aggregate. Water sensitivity in the ECS is significant for combinations of asphalt and aggregate. The ECS test results have shown that ECS performance ranking after one cycle is not statistically significant and does not correlate with ranking after three cycles. The results show that the ECS test program has similar aggregate rankings to those of the NAT and SWK/UN test program, while good agreement exists between SWK/UN wheel tracking results and the NAT test program results. However, poor agreement exists between the OSU wheel tracking results and those of the other two tests. Poor or very little agreement exists among the wheel tracking test results, ECS, and NAT test results in terms of asphalt type rankings. When considering the comparisons of materials ranking by different test procedures, one must keep in mind that the mechanisms leading to varying "performance" are not the same. The testing reported herein was aimed at measuring water sensitivity, but all the tests do not do so directly. The NAT procedure addresses only the potential for stripping (adhesion) and is not capable of evaluating cohesion loss. The other tests (ECS, OSU and SWK/UN wheel tracking) included all the mechanisms simultaneously, and these provided a gross effect without clearly separating the cause of failure in each case. Open-graded mixtures used by Oregon Department of Transportation (ODOT) performed well in the ECS in terms of water sensitivity. In the ECS evaluation, six mixtures passed the criteria of 75 % established for Indirect Retained Strength (IRS) test by ODOT, and one mixture was marginal. However, only one mixture passed the IRS evaluation, and another mixture was marginal. This confirms that the IRS test is a very severe test and is not suitable for water sensitivity evaluation of open-graded mixtures. Finally, the IRS test evaluation would suggest that these mixtures would fail prematurely after construction, but all of these mixtures have been used in projects which have been in service for more than three years with no visible signs of distress, or failures. / Graduation date: 1994

Thermal cracking of asphalt concrete pavements is responsible for millions of dollars in annual maintenance and rehabilitation costs in the United States and Canada. Thermal cracking is typically associated with low temperatures in northern climates and at high elevations. However, another form of thermal cracking, known as thermal fatigue cracking, has been proposed by several researchers as a potential mode of distress in regions with relatively moderate climates but significant differences in high and low daily temperatures. The primary purpose of the research reported herein was to evaluate the possibility of occurrence of the thermal fatigue cracking mode of distress. A secondary objective was to identify a suitable laboratory test procedure to facilitate a mechanistic analysis of the thermal fatigue mode of distress. In light of these objectives, several laboratory test procedures were evaluated in the bituminous materials laboratory at Oregon State University (OSU). The test procedures evaluated included the phenomenological Thermal Stress Restrained Specimen Test (TSRST), the Energy Rate Integral Test (ERIT), the Direct Tension Test under constant rate of extension (DTT), and the Direct Tensile Creep Test (DTCT). The TSRST results were used to evaluate the possibility of occurrence of the thermal fatigue mode of distress. The ERIT, DTT, and DTCT procedures were evaluated with respect to the identification of a suitable laboratory test procedure to facilitate a mechanistic analysis of thermal fatigue. The results from the laboratory test program indicate that thermal fatigue distress in asphalt concrete mixtures is not a viable mode of distress in the absence of environmental aging. Based on the data presented herein and the results of previous researchers, it is evident that distress often attributed to thermal fatigue cracking is more likely the result of low temperature cracking of environmentally aged mixtures, and/or subgrade-related distress; fatigue distress due to thermal loading of semi-restrained pavements does not occur. / Graduation date: 1993

Thesis (Ph. D.)--University of Tennessee, Knoxville, 2003. / Title from title page screen (viewed Sept. 26, 2003). Thesis advisor: Eric C. Drumm. Document formatted into pages (xx, 249 p. : ill. (some col.)). Vita. Includes bibliographical references.