【作者】 许飞；

【导师】 薛武平； 李慧民；

【作者基本信息】 西安建筑科技大学 ， 结构工程， 2011， 硕士

【摘要】 现在我国的经济飞速发展,经济水平日新月异。各种建筑层出不穷,对设计和结构的要求也要增高,同时在各个工业和民用建筑中,大体积混凝土大量地应用。大体积混凝土的裂缝是其应用中不可避免的问题,也是混凝土应用中经常需要考虑的问题,一旦混凝土出现裂缝,对其稳定性,耐久性都会产生影响。甚至会产生一定的危险,所以对混凝土的裂缝问题研究具有十分必要的意义。本文从大体积混凝土的定义出发,介绍大体积混凝土裂缝的类型,然后从理论方面解释大体积混凝土裂缝产生的机理和主要影响因素。揭示出温度裂缝主要是由于水化热和内外温差所产生的。所以在施工中必须控制水泥的水化热以及通过养护的方式来降低内外温差。具体的方法有:1、从设计的方面控制。设计方面主要是从混凝土强度的选择,尽量利用后期强度高的混凝土。配筋的方法和预留缝的设置来控制。2、从材料的选择中采取措施。分别对水泥、骨料、外加剂上的选择。来控制裂缝的产生。3、从施工和养护的方面来控制。最后本文通过对“西安市某地区棚户区改造项目”的实际案例,来具体介绍这些控制方法的可行性和具体操作,通过理论的计算和实际的测量结果的对比,以及用MIDAS有限元软件来证明这些控制方法的合理。为大体积混凝土以后的施工提供一定的参考。更多还原

【Abstract】 With the rapid devolopment of our country economy, the various structures become more and more,meanwhile the demand of the design and the construction are improved. mass concrete is used in the industry and civil buildingThe question of mass concrete crack is inevitable in mass concrete’s using.once the crack appears in the concrete,The stability and the durability would be affected,even become some danger.The study of mass concrete crack is very necessary.This paper starts from the definition of mass mass concrete, introduces types of mass concrete crack,then explains the mechanisation of production of mass concrete crack and major factors. It reveals that the main reason is heat of hydration and Internal and external temperature difference. So it should control the heat of hydration and cut down the temperature difference. Specific methods:1.Control from design side. The methods main have choice of concrete strength, using later concrete strength, ways of reinforcement .2.Action from choice of the material . choose from the cement, aggregate and admixture. to control the cracks.3.Control from construction and conservation.At last, the paper uses by lejuchang shantytowns project to introduce feasibility and operational of these control methods. By contrast theoretical calculation and practical measurement,and use MIDAS to prove rationality of these control methods and provide a reference for future projects.更多还原