配筋方式对混凝土沟盖板早龄期收缩特性的影响
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摘要
混凝土沟盖板早龄期收缩变形所引起的开裂问题普遍存在,而配筋方式是其中的重要影响因素。为此,依据某电力公司沟盖板原配筋方案及其优化配筋方案,基于ABAQUS有限元软件模拟分析了不同配筋方式对混凝土沟盖板早龄期收缩特性的影响,并计算了沟盖板于相应龄期发生开裂的环境温差阈值。结果表明,横向构造钢筋拉通不利于混凝土抵抗早龄期收缩应力;在相同配筋情况下,增设钢丝网不利于混凝土抵抗早龄期收缩应力;配筋率增大、钢筋与角钢框焊接均不利于混凝土抵抗早龄期收缩应力。
The cracking problem caused by the shrinkage deformation of reinforced concrete cover plate at early age is widespread and reinforcement arrangements are important influencing factor.According to primary and optimized reinforcement arrangements of the cover plate of a provincial electric power company,simulation analyses of effects on earlyage shrinkage characteristics of the cover plate were conducted and environmental temperature difference thresholds of corresponding age of the cover plate for cracking in free boundary condition were calculated based on FEM software ABAQUS.Research shows that the pulling-through of transversal structural steel bars is adverse to resist early-age concrete shrinkage stress;the additional steel wire mesh has adverse action to resist early-age concrete shrinkage stress when placing of steel bars are identical;it's unfavourable to resist early-age shrinkage stress when increasing the reinforcement ratio to a certain extent;the welding between reinforced and angle iron frame is not conducive to resist early-age shrinkage stress.
The cracking problem caused by the shrinkage deformation of reinforced concrete cover plate at early age is widespread and reinforcement arrangements are important influencing factor.According to primary and optimized reinforcement arrangements of the cover plate of a provincial electric power company,simulation analyses of effects on earlyage shrinkage characteristics of the cover plate were conducted and environmental temperature difference thresholds of corresponding age of the cover plate for cracking in free boundary condition were calculated based on FEM software ABAQUS.Research shows that the pulling-through of transversal structural steel bars is adverse to resist early-age concrete shrinkage stress;the additional steel wire mesh has adverse action to resist early-age concrete shrinkage stress when placing of steel bars are identical;it's unfavourable to resist early-age shrinkage stress when increasing the reinforcement ratio to a certain extent;the welding between reinforced and angle iron frame is not conducive to resist early-age shrinkage stress.
引文
[1]惠云玲,弓俊青,郝挺宇.工程结构裂缝诊治技术与工程实例[M].北京:中国建筑工业出版社,2007.
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[3]徐可,高德军,徐港,等.基于ANSYS的预制混凝土T型梁裂缝成因分析[J].水电能源科学,2012,30(4):44-47.
[4]侯景鹏.钢筋混凝土早龄期约束收缩性能研究[D].上海:同济大学,2006.
[5]李如群,沙敏.钢筋对混凝土收缩变形分布的影响[J].低温建筑技术,2013,35(6):26-28.
[6]韩文.大体积混凝土设备基础的温度监测及数值仿真[D].保定:河北农业大学,2014.
[7]李先明.水工钢筋混凝土结构温度场及温度应力仿真系统研究[D].南京:河海大学,2006.
[8]许锴.现浇钢筋混凝土板收缩裂缝的定量分析方法初探[J].广东土木与建筑,2001(6):83-85.
[9]GB50010-2010,混凝土结构设计规范[S].北京:中国建筑工业出版社,2010.
[10]GB/T50152-2012,混凝土结构试验方法标准[S].北京:中国建筑工业出版社,2012.
[11]王铁梦.工程结构裂缝控制[M].北京:中国建筑工业出版社,2005.
[12]李尊忠,何宁,崔冬.某电厂贮煤筒仓基础大体积混凝土施工技术[J].工业建筑,1999,29(12):68-71.
[13]陈萌.混凝土结构收缩裂缝的机理分析与控制[D].武汉:武汉理工大学,2006.
[2]王纪跃,钱晓倩.钢筋对混凝土收缩应力的影响[J].混凝土,2004(12):3-4,18.
[3]徐可,高德军,徐港,等.基于ANSYS的预制混凝土T型梁裂缝成因分析[J].水电能源科学,2012,30(4):44-47.
[4]侯景鹏.钢筋混凝土早龄期约束收缩性能研究[D].上海:同济大学,2006.
[5]李如群,沙敏.钢筋对混凝土收缩变形分布的影响[J].低温建筑技术,2013,35(6):26-28.
[6]韩文.大体积混凝土设备基础的温度监测及数值仿真[D].保定:河北农业大学,2014.
[7]李先明.水工钢筋混凝土结构温度场及温度应力仿真系统研究[D].南京:河海大学,2006.
[8]许锴.现浇钢筋混凝土板收缩裂缝的定量分析方法初探[J].广东土木与建筑,2001(6):83-85.
[9]GB50010-2010,混凝土结构设计规范[S].北京:中国建筑工业出版社,2010.
[10]GB/T50152-2012,混凝土结构试验方法标准[S].北京:中国建筑工业出版社,2012.
[11]王铁梦.工程结构裂缝控制[M].北京:中国建筑工业出版社,2005.
[12]李尊忠,何宁,崔冬.某电厂贮煤筒仓基础大体积混凝土施工技术[J].工业建筑,1999,29(12):68-71.
[13]陈萌.混凝土结构收缩裂缝的机理分析与控制[D].武汉:武汉理工大学,2006.