摘要
地铁车站超长结构混凝土施工主要是采用分段浇筑的工法,超长混凝土结构的裂缝控制是需要解决的一个主要问题。为此,采用有限元模拟来分析该类超长结构混凝土梁的结构内部应变分布情况,并通过对混凝土梁进行温度和应变的现场测试,得出梁产生裂缝的主要原因是由于分段浇筑引起混凝土温度和湿度收缩不同步。通过采取相应的防裂技术措施,可以有效控制混凝土的裂缝问题。对在降温过程中产生的应变采用灰色系统理论建立GM(1,1)预测模型,结果表明GM(1,1)预测模型具有较好的拟合精度,可有效预测混凝土在变形过程中产生的应变,为及时采取有效的抗裂控制措施提供理论指导。
Segmented pouring method is mainly used in extra long concrete structures of subway station.The major problem of cracks control of extra long concrete structure is facing.To solve the problem of cracks in extra long concrete beam structure of subway station,the distribution of internal strain of concrete beam was analyzed by the finite element model.And then strain gauges and thermocouple probe were installed on concrete beam and the indexes of strain and temperature were monitored.The results show that the root cause of beam cracks is due to not synchronize of concrete shrinkage cause of break pouring, and the unsynchronized shrinkage was including temperatm＇e and humidity shrinkage.The problem of cracks was controlled effectively after taking some appropriate technical measures according to the causes of cracks.Prediction model GM（ 1, 1 ） of grey system theory was established for strain of concrete structure in the cooling process.And the results show that the model had a preferable fitting accuracy which can effectively predict the strain of concrete in the process of defor- mation.The model can provide theoretical guidance for taking effective control measures in a timely manner for cracking.
出处
《混凝土》
CAS
北大核心
2017年第3期150-153,共4页
Concrete
基金
广西科学研究与技术开发计划--超长结构混凝土裂缝控制研究与应用技术(桂科合14251002)
关键词
超长结构
混凝土梁
温度
应变
灰色预测模型
extra long structure
concrete beam
temperature
strain
gray prediction model
