西部铁路大体积混凝土防裂技术研究  

Research on crack prevention of mass concrete in western railway

作　　者：仲新华[1] 楼梁伟[1] 朱长华[1] 李享涛[1] 

机构地区：[1]中国铁道科学研究院铁道建筑研究所高速铁路轨道技术国家重点实验室,北京100081

出　　处：《混凝土》2014年第12期122-124,127,共4页Concrete

摘　　要：我国西部地区具有大温差和大风速的环境特点,为了比较分析温差和风速对大体积混凝土抗裂性的影响,采用数值模拟技术量化计算了混凝土的温度和应力分布。结果表明,大温差和大风速条件下,混凝土具有较高的内外温度梯度和拉应力,特别是具有较高的早龄期拉应力,这是大体积混凝土开裂的主要原因,混凝土带模养护期间的保温和保湿养护是预防混凝土开裂的主要措施。进一步研究表明,采用保温养护技术可显著降低混凝土的内外温度梯度,采用透水无纺布衬里模板技术和预吸水组分内养护技术可有效延长混凝土湿养护时间,是现阶段降低大体积混凝土开裂风险的主要措施。Based on the environmental characteristics of large temperature difference and wind speed in China’s western region ,numeri-cal simulation technology had been used to calculate the temperature and stress distribution of concrete in order to analysis the influence of temperature and wind speed on the crack resistance of mass concrete.The results show that the larger the temperature difference and the wind speed,the higher the external temperature gradient and the tensile stress is,particularly at the early stage,which is the main reason inducing the cracking of mass concrete.Furthermore,mold with insulation and moisture conservation during the curing period of concrete is a significant measure to prevent cracking of concrete. It also indicates that using heat insulation form technology can remarkably reduce the inside and outside temperature gradient,and permeable non-woven fabric lining template and pre-absorbent components within conservation technologies can effectively prolong the wet-curing time as well.They are the main measures to decrease the cracking risk of mass concrete in western railway at present.

关 键 词：大体积混凝土 数值模拟 温度梯度 防裂措施 

分 类 号：TU528.01[建筑科学—建筑技术科学]