Influence of long-term load and chlorine corrosion on reinforced concrete beam deflection
HE Shiqin1, CAO Zeyang1, LIU Weijie2, LI Pengfei3
1. School of Civil Engineering, North China University of Technology, Beijing 100144, China; 2. Beijing Fayan Engineering Technology Co., Ltd., Beijing 100102, China; 3. School of River and Ocean Engineering, Chongqing Jiaotong University, Chongqing 400074, China
Abstract：This study predicts the long-term deformation of reinforced concrete (RC) beams in corrosive environments which is important for ensuring the long-term strength and durability of structures. The long-term deformation of RC beams was measured for the coupling action of the load level and chloride corrosion environment. The long-term deflection of the beams was compared with predictions of the ACI209R model. The results show that the beam deflection when affected by load-chloride corrosion can be divided into four stages:the deflection increased rapidly in the first 10 d, the growth rate slowed after 10 d, the growth rate further decreased after 150 d, and the deflection rate started to increase again after 300 d. Alternating dry and wet environments caused the deflection rates to go up and down. The load level has an evident influence on the RC beam deflection in the corrosive environment. The ACI209R prediction model does not accurately predict the test results because it does not consider the coupled effect of the reinforcement corrosion.
何世钦, 曹泽阳, 刘伟杰, 李鹏飞. 长期荷载和氯盐环境耦合作用对钢筋混凝土梁挠度的影响[J]. 清华大学学报（自然科学版）, 2019, 59(11): 902-909.
HE Shiqin, CAO Zeyang, LIU Weijie, LI Pengfei. Influence of long-term load and chlorine corrosion on reinforced concrete beam deflection. Journal of Tsinghua University(Science and Technology), 2019, 59(11): 902-909.
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2019, Vol. 59 
