基于核磁共振技术对不同粗骨料混凝土孔隙特征试验研究

摘要

基于核磁共振(NMR)测试技术,选取红浮石、黑浮石和碎石为粗骨料,研究不同粗骨料混凝土内部孔隙特征,并对混凝土进行抗压强度试验.结果表明,龄期为28 d混凝土强度由高到低顺序为碎石混凝土＞黑浮石混凝土＞红浮石混凝土,浮石混凝土T2谱分布主要为2个峰,碎石混凝土T2谱分布主要为3个峰,且T2谱面积由大到小为红浮石混凝土＞黑浮石混凝土＞碎石混凝土,浮石混凝土中毛细孔和非毛细孔总和所占比例大于碎石混凝土.%Based on NMR measurement technology,selecting natural red pumice,black pumice and gravel as coarse aggregate,studies on the pore characteristics of concrete with different coarse aggregate were carried out,and the compression strength of concrete was tested.The results show that the strength of concrete with the age of 28 d declines in sequence from ordinary gravel concrete,black pumice concrete to red pumice concrete.Natural pumice concrete has mainly two peaks in NMR T2 spectrum,while ordinary gravel concrete hasthree.T2 spectral areashows a sequence from large to small as red pumice concrete ＞ black pumice concrete ＞ ordinary gravel concrete.Theproportion of the sum ofthe pores and the non capillary pores in natural pumice concrete is higher than that of ordinary gravel concrete.