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The recent rapid economic and population growth in the State of California have led to a significant increase in air conditioning use, especially in areas of the State with coastal and transitional climates. This fact makes the electric peak demand to be dominated by air conditioning use in buildings during the summer time. However, this extra peak demand caused by the use of air conditioning equipment lasts only a few days out of the year. As a result, avoidable power outages occur when power utilities do not keep up with such demand. This paper proposes a possible solution to this problem by using building thermal mass via phase change materials to reduce peak air conditioning demand loads. This proposed solution was tested using a wall herein referred to as phase change frame wall (PCFW). The PCFW is a typical residential frame wall in which Phase Change Materials (PCMs) were integrated to add thermal mass. The thermal performance of PCFWs using a hydrated salt PCM was evaluated via computer simulations of residential buildings located in coastal and transitional climates in California. Simulated results indicated that the PCFWs would reduce the space cooling load by an average of 10.4%. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents experimental results on the improvement of the California Bearing Ratio (CBR) performance of fine-grained soils by the addition of geofiber and synthetic fluid. CBR tests were conducted for freezing and thawing conditions in addition to non-freezing conditions. The improvement of soil was tested with the inclusion of: i) geofiber only, ii) synthetic fluid only, and iii) synthetic fluid and geofiber together. To represent unsaturated and saturated soil conditions for various field applications, both unsoaked and soaked samples were investigated. The results for unsoaked conditions indicated significant improvement in the CBR performance, particularly in samples treated with geofiber and synthetic together. For soaked conditions, the best performance was obtained from the samples treated with geofiber only. The CBR performance of samples subjected to a freeze–thaw cycle was also tested. Freezing and thawing tests on unsoaked samples showed that the addition of geofiber together with synthetic fluid was generally successful in providing resistance against freeze–thaw weakening, and that the addition of synthetic fluid alone was not very effective against the detrimental impact of freeze–thaw. The results from soaked samples subjected to a freeze–thaw cycle showed poor CBR performance for treatments involving synthetic fluid while samples improved with geofibers alone generally produced better performance. [Copyright &y& Elsevier]