寒冷地区海洋环境下高性能混凝土时变特性试验研究  

Experimental Study on Time-varying Characteristics of High-performance Concrete in Marine Environment in Cold Regions

作　　者：冯博[1] 朱海[1] 钱永久[1] FENG Bo;ZHU Hai;QIAN Yongjiu(School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China)

机构地区：[1]西南交通大学土木工程学院,四川成都610031

出　　处：《铁道学报》2024年第1期183-193,共11页Journal of the China Railway Society

基　　金：国家自然科学基金(51778532)。

摘　　要：依托河北唐山市内曹妃甸区纳潮河2#大桥,针对寒冷地区海洋环境下高性能混凝土(HPC)的时变特征演化规律,开展桥位同位同因素下HPC的时变性能试验研究,且把试件每个变量实际测量数值和规范标准预估值做比较,结果表明:寒冷地区海洋环境下的HPC的早期抗压强度提升速度明显高于规范预测值,抗压强度呈现早期发展迅速,后期缓慢的趋势;寒冷地区海洋环境下HPC弹性模量早期进展速度快,但初期进展相对落后于抗压强度发展趋势。采取抗压强度演算HPC的弹性模量显然小于实际测量值;寒冷地区海洋环境下HPC收缩应变同样在初期收敛速度很快,后期收敛速度趋缓,此外试件构件尺寸大小不但与收缩应变的最终数值有关,同时影响收缩应变随时间发展进程;针对寒冷地区海洋环境下HPC的收缩和徐变发展特性,基于试验结果,分别提出基于CEB-FIP—2010的收缩参数修正模型以及基于EN 1992-2—2005的徐变预测修正公式。Aiming at the time-varying characteristic evolution law of high-performance concrete(HPC)in the marine environment in cold regions,based on the No.2 Bridge of Nachao River in Caofeidian District,Tangshan City,Hebei Province,an experimental investigation was carried out on the time-varying performance of HPC under the same bridge location and factors.The actual measured value of the specimen was compared with the predicted value of specifications and standards.The results show that:The increase of early compressive strength of HPC under the marine environment in cold regions is significantly higher than the predicted value of the specifications,and the compressive strength shows a trend of rapid development in the early stage and slow development in the later stage;the early progress of HPC elastic modulus in the marine environment of cold regions is fast,but the initial progress is relatively lagging behind the development trend of compressive strength.The elastic modulus of HPC calculated by compressive strength is obviously smaller than the actual measured value;the shrinkage strain of HPC in the marine environment in cold regions also has a fast convergence rate in the initial stage and a slower convergence rate in the later stage.In addition,the size of the specimen member is not only related to the final value of the shrinkage strain,but also affects the development process of the shrinkage strain with time;aiming at the shrinkage and creep development characteristics of HPC in the marine environment in cold regions,according to the test results,the shrinkage parameter correction model based on CEB-FIP—2010 and the creep prediction correction formula based on EN 1992-2—2005 are respectively proposed.

关 键 词：寒冷地区 高性能混凝土 时变性能 收缩徐变 预测模型 

分 类 号：U447[建筑科学—桥梁与隧道工程]