建筑工程用泵送高抛自密实混凝土的施工性能研究

Application of C40 pumped high throwing self-compacting concrete in building construction

通过控制水胶比与胶凝材料总量等参数,采用粉煤灰与矿粉双掺及流变调控技术,所制备泵送C40自密实混凝土扩展度680mm、T500时间4.5s、J环高差11mm、L仪高度比0.92,较好满足了现场泵送高抛施工需要。拆模后的混凝土结构内部均匀密实,外观质量良好,解决了配筋密集与大落差导致的混凝土易离析与难振捣难题。

By optimizing the parameters such as water binder ratio and total content of cementitious materials,and adopting the double mixing of fly ash and mineral powder and rheological control technology,the properties of C40 pumped self-compacting concrete,such as slump expansion 670mm,T500 time 4.5s,J ring height difference 12mm and L meter height ratio 0.92,better meet the needs of on-site pumping high throwing construction.The concrete structure after demolding is uniform and dense internally,with good appearance quality,solving the problems of easy segregation and difficult vibration of concrete caused by dense reinforcement and large drop.