大体积粉煤灰混凝土强度发展及养护方式研究

Large volume fly ash concrete strength development and maintenance mode research

大体积粉煤灰混凝土在桥梁工程中普遍存在,通过研究不同养护温度下其强度发展特点,相对应地在工地现场采用标准养护、同条件养护、温度匹配养护等方式,制造试验墩并引入成熟度方法进行计算验证.结果表明:(1)最终选取的混凝土配合比,应保证其试块实测最高温度及温度变化范围与原估计值基本相当,内部中心温度不超过60℃为宜;(2)大体积混凝土中心内部适宜采用温度匹配养护方式,表层混凝土可使用同条件养护方式;(3)成熟度方法利用标准养护试块强度即可预测现场大体积混凝土强度,是一种简易可行的方法.出于安全角度考虑,计算结果应减小5%进行计算.

Mass Fly Ash Concrete is extensive used in bridge engineering, To Reveals concrete strength development characteristics By studying different curing temperatures Contrastion, Use of standard maintenance, the same curing condition, temperature match curing three ways in Construction site, Manufacturing Test pier and the introduction of maturity calculation method to validation. The results show：（1） Final selection of the concrete mix, which should ensure the highest measured temperature of the test piece and temperature range is roughly equal to the original estimates, the internal center temperature not excee- ding 60 ~C appropriate; （2） mass concrete＇s Internal center appropriateness of using temperature match curing method, the surface of concrete ways you can use the same curing condition; （3） Maturity method using a standard conservation test block to predict field strength massive concrete strength, is a simple and feasible method. For security point of view, the results should be reduced 5 % calculation.