科特迪瓦某重力式码头胸墙开裂原因分析及裂缝控制对策

Causes analysis and control countermeasures of cracks in a gravity wharf breast wall in Cote d'Ivoire

针对科特迪瓦某重力式码头胸墙浇筑后出现多条竖向裂缝的问题,采用有限元软件对胸墙进行开裂风险评估,对水泥进行Rietveld全谱测试,从多角度分析胸墙的开裂原因,并给出胸墙控裂对策。结果表明:胸墙的外约束应力过大是导致其开裂的直接原因,而混凝土水化热温升过高、凝结时间过短及混凝土降温速率过快是导致开裂的深层次原因。通过优化混凝土配合比、控制混凝土内外温差、改善施工工艺等措施有效控制了裂缝的产生,后期浇筑的胸墙裂缝数量明显减少,胸墙控裂取得成功。

Aiming at the problem of multiple vertical cracks in the breast wall of a gravity wharf in Cote d'Ivoire,we used finite element software to evaluate the cracking risk of the breast wall and conducted a Rietveld full-spectrum test on the cement.The reasons for the cracking of the breast wall were analyzed from various perspectives,and the countermeasures to control the cracks were given.The results show that the excessive restraining stress of the breast wall is the direct cause of its cracking.In addition,excessive heat of hydration,short setting time and too fast cooling rate of concrete are the deep-seated causes of cracking.By optimizing the concrete mix ratio,controlling the temperature difference between the inside and outside of the concrete and improving the construction technology,the occurrence of cracks was effectively controlled.The number of cracks on the post-pouring breast wall was significantly reduced in the later stage,and the control of the cracks was successful.