西北地区道面混凝土抗裂性研究与应用

Study and application on the crack-proof property of pavement concrete in the northwest China

针对西北地区机场道面铺筑水泥混凝土后经常出现早期裂缝的现象,为找到既能大幅度减少混凝土早期开裂又能满足设计要求的混凝土材料,采用在普通混凝土中单掺合成纤维或粉煤灰以及合成纤维与粉煤灰复合的技术路线,研究配制高抗裂的高性能道面混凝土,并采用平板法对其早期抗裂性进行试验研究。试验和应用结果表明:单掺粉煤灰或合成纤维的道面混凝土,早期抗裂性显著提高;尤其是合成纤维与粉煤灰复合产生了"1+1>2"的超叠加综合效应,更能够全面提高道面混凝土的早期抗裂性,这种混凝土是适合西北寒冷干旱地区的新型高性能道面混凝土。

The stady aimed at the phenomenon of early cracks after the construction of airport pavement cement concrete slab in the Northwest China, in order to find concrete materials which could reduce the early cracks greatly and satisfy the design requirements, the ordinary concrete was mixed with fly ash or synthetic fibre or both, study and confect high performance pavement concrete with high crack-proof property, the test with plate specimen is adopted to examine the early-age crack-proof property of concrete.The results indicated that early-age crack-proof property of fly ash concrete and synthetic fibre concrete was enhanced greatly; especially the compound of synthetic fibre and fly ash brings the ＂1＋1〉2＂ super duble synthetical effect,which improves the early crack-proof property of pavement concrete comprehensively,the concrete is the right new type high performance pavement concrete for the Northwest China that cold and droughty.