关键词: 戈壁环境;箱梁裂缝;抗裂性;混凝土强度

Abstract: In order to study the effect of curing methods on crack resistance and strength of precast concrete box girder in Gobi,Gansu Province,firstly,we surveyed the weather conditions at the site and selected three maintenance schemes. Then we tested and analyzed the strength of the box girder and the development of the crack under different curing methods,the results show:the concrete strength and the ratio of tensile and compressive strength of the concrete are gradually reduced,and the cracking resistance is gradually weakened;steam curing is the best maintenance method in Gobi area;the width of cracks in Gobi area is mainly distributed in 0 . 00-0 . 02 mm and 0 . 03-0 . 04 mm two intervals;the maintenance of concrete box girder in Gobi area should not only pay attention to moisture conservation, but also strengthen the insulation. Finally,this paper puts forward some suggestions on the prevention and control of cracks in precast concrete box girder in large temperature difference,dry and strong wind area combined with the test and field construction.

Key words: gobi;box girder crack;anticrack property;concrete strength