MgO微膨胀混凝土筑坝技术述评

Review on Dam Construction Technology with MgO Micro-expansion Concrete

外掺MgO微膨胀混凝土坝体防裂技术可有效补偿坝体在降温期的拉应力。从MgO应力补偿的基本原理出发,介绍了MgO混凝土材料性能、膨胀模型、施工方法及安全监测等方面的研究现状,分析了MgO微膨胀混凝土筑坝技术在推广应用中存在的突出问题,从MgO混凝土高掺量的体积安定性、考虑多因素的精确膨胀模型、外掺MgO与其他温控措施的配套使用等方面探讨了亟待攻克的技术难点和发展方向。

The crack prevention technique of the mixed MgO micro-expansion concrete dam can effectively compensate for the tensile stress during the cooling period.Based on the principle of stress compensation with MgO,current researches on properties of MgO concrete material,expansion models,dam construction method and safety monitoring are presented.At the same time,some key issues are discussed about promoting dam construction technology with MgO micro-expansion concrete.Finally,a number of pressing issues and development direction on dam construction technology are discussed,which includes the aspects of volume stability of high added MgO concrete,accurate expansion model considering multi-factors and combination of conventional temperature control measures with technology of mixed MgO.