掺和料对塑性混凝土的性能影响研究

Study on the Impact of Admixture on the Performance of Plastic Concrete

塑性混凝土在水利工程的防渗墙中被广泛应用,在其拌制过程中,使用的掺和料不同,其强度和弹性模量等性能也不同。为了更好地满足工程质量和环保要求,选取三种常见的掺和料进行配合比试验。以塑性混凝土的配合比为基准,分别加入粉煤灰、胶粉和硅灰三种掺和料,形成四种不同的试验配合比,试验分析这五种塑性混凝土配合比拌合物的和易性情况、力学性能和抗渗性能,从而得出三者中胶粉对拌和物和易性影响最大,粉煤灰次之,硅灰最小;粉煤灰和胶粉能降低塑性混凝土强度和弹性模量,硅灰则能提高强度和混凝土弹性模量;粉煤灰和硅灰能提高塑性混凝土的抗渗性能,胶粉则能降低。三者混掺则和易性及抗渗性有所增加,强度和弹性模量减小。

Plastic concrete is used widely in diaphragm wall of water conservancy project. In the process of mixing,strength and elastic modulus were different with the different of admixture. With the request of water conservancy projects on the quality and environmental protection,three kinds of common admixture were selected to carry out mix proportion tests. Used ordinary mix proportion of plastic concrete as a benchmark,three kinds of admixture were mixed,which form of four different of mix proportion test,ultimately selecting fly ash,rubber powder and silica fume mixed with ordinary plastic concrete,at the same time,researching the workability,mechanical properties and impermeability of mixed plastic concrete,the main research contents are reached: for three admixtures ranked according to the impact degree on the workability from big to small,the order is as follows:rubber powder,fly ash and silica fume;fly ash and rubber powder can decrease strength and elastic modulus,silica fume can increase them;fly ash and silica fume can increase impermeability;rubber powder can decrease impermeability;mixing three kinds of admixture,workability and impermeability can be increased,strength and elastic modulus can be decreased.