添加下水道污泥灰渣對於高性能混凝土影響之研究

Effects of Sewage Sludge ASH on High Performance Concrete

本研究利用緻密配比法探討添加當作細骨材的下水道污泥灰渣對高性能混凝土配比及抗壓強度之影響，水膠比有0.28、0.32、0.36、0.40 及0.44 等五種；下水道污泥灰渣佔細骨材之比例為0%、5%、10%及15% 等四種；混凝土抗壓強度齡期為3、7、28 及56 天。結果顯示，添加適量的下水道污泥灰渣，產製成高性能混凝土，其抗壓強度略有提高之情形，為維持混凝土固定水膠比及緻密配比，混凝土之單位強塑劑用量隨著污泥灰渣含量增加而增加，單位用水量則為減少之趨勢；污泥灰渣最佳含量隨著水膠比增加而增加；若過量添加污泥灰渣會影響混凝土抗壓強度及工作度，顯示混凝土中添加下水道污泥灰渣之應用具有可行性。

This study focuses primarily on the use of recycled sewage sludge ash(SSA) as part of the fine aggregate in High Performance Concrete (HPC)designed using the Densified Mixture Designed Algorithm (DMDA).Four replacement ratios of the fine aggregate, 0%, 5%, 10% and 15%, andfive paste qualities, expressed as W/b (water-to-binder) ratios of 0.28, 0.32,0.36, 0.40 and 0.44, are the parameters utilized to discuss the effects at three, seven, 28, and 56 days. Experimental results demonstrate that thecompressive strength of HPC is slightly improved when made with theproposed mixtures containing appropriate amounts of SSA. Under a fixedW/b ratio and using DMDA, the dosage of superplasticizer (SP) utilized inconcrete increases as the amount of SSA increases and water content decreases.The optimum SSA content increases as the W/b ratio increases.An excessive amount of SSA affects workability and compressive strength.Results indicate that using sewage sludge ash in concrete is feasible.