现场施工条件下,混凝土气密性能受到多种外界因素的影响,试验研究了搅拌时间、拌合物静置时间、养护条件、振捣时间对混凝土气密性能的影响。研究结果表明:拌合物搅拌时间为3 min时混凝土的透气系数最小;拌合物静置时间宜控制在45 min以内;标准养护条件下混凝土的透气系数是最小的,同条件养护次之,而自然养护最差;混凝土浇筑时振捣时间以20—30 s为宜。 Under the condition of on-site construction, the airtightness of concrete is affected by many external factors. The effects of mixing time, standing time of mixture, curing conditions and vibrating time on the airtightness of concrete are studied. The results show that: the aeration coefficient of concrete is the minimum when the mixing time is 3 min; the standing time of the mixture should be controlled within 45 min; the concrete aeration coefficient is the smallest under the standard curing conditions, While the worst natural conservation; vibrating concrete pouring time to 20-30 s is appropriate.