大浦第二抽水站进水流道层混凝土裂缝控制措施

Concrete crack control measures in Dapu No. 2 Pumping Station water intake channel layer

大浦第二抽水站为块基型堤身式结构,沉井基础,肘形进水流道层变截面,大体积混凝土在沉井基础约束下极宜产生裂缝。通过分析裂缝产生原因,综合考虑原材料、配合比、结构尺寸、配筋、约束程度、养护条件等多种因素影响,采取控制混凝土坍落度、砌块石芯墙、混凝土中掺加防裂纤维和埋设冷却水管等一系列防裂和控制裂缝措施,有效地控制裂缝发生,取得了明显效果。

Dapu No. 2 Pumping Station belongs to block foundation embankment structure. Open caisson foundation,elbow-type water intake flow channel layer variable cross-section and large-volume concrete can produce cracks easily under open caisson foundation constraints. Influence of various factors are considered comprehensively through analyzing crack reasons,such as raw materials,mixing ratio,structure size,rib mixing,constraint degree,curing condition,etc. A series of anti-crack and crack control measures are adopted,wherein concrete slump is controlled,stone core wall is built,concrete is mixed with anti-crack fiber,cooling water pipe is embedded,thereby effectively controlling crack,and obtaining prominent effect.