The Study of Controlled Low Strength Material Using Sandy Soils from Trench Excavation Mixed with Bottom Ash

• Main Authors: Sung-Chi Lu, 呂松吉
• Other Authors: Tzyy-Shiou Chang
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/d9fa6b

碩士 === 朝陽科技大學 === 營建工程系碩士班 === 96 === The study was designed to investigate the mechanical properties of controlled low strength material (CLSM) with the use of re-cycled construction materials such as sandy soils from trench excavation and bottom ash from power plant furnace. A series of tests were conducted at 3 water/cement ratios (1.41, 1.71, and 2.18) and sand soils mixed with bottom ash for selected volume percentages (100:0, 80:20, and 60:40). The results of study indicated that the compressive strength of CLSM is mainly dependent upon the w/c ratio. The lower w/c ration resulted in higher strength of CLSM, especially when w/c ratio is smaller than about 1.6~1.75, the strength increases even more significantly. The results of study also revealed that strength of CLSM also increases with increasing volume percentage of the bottom ash. However, the study preliminarily concluded that the increase tends to become lesser when the bottom ash is greater than about 20-25%. In addition, the results of the study also revealed a preliminary finding that when w/c ratio is smaller than 2.5, the strength of CLSM could be enhanced by properly increasing the volume percentage of bottom ash. This water/cement ratio of 2.5 should be confirmed by further tests and study. For the practical application of the CLSM in the field, the study suggested that w/c ratio between 1.4-2.2 and volume percentage of bottom ash between 20-40% may be used in accordance with project requirements in terms of strength and workability.