水下自护混凝土与钢筋握裹力试验研究OA北大核心CSTPCD

Self-protected underwater concrete(SPUC)is widely used in concrete projects,as the key pa-rameter of SPUC,the concentration of underwater protective agent(UPA)has a significant impact on the structural performance of SPUC,which has become the research focus nowadays.Based on SPUC tech-nique,experimental studies on the mechanical properties of plain SPUC,the bond strength between SPUC and steel bars,and the microstructure of SPUC pores under the commonly used working concentra-tions were conducted.The results showed that the water-to-ground strength ratio of plain SPUC compres-sive strength was over 80%at different concentrations of UPA;the water-to-ground strength ratio of the bond strength between SPUC and steel bars was about 40%-65%,and the higher the concentration of UPA,the lower the water-to-ground strength ratio of the bond strength between SPUC and steel bars.In addition,the porosity of the concrete matrix region is negatively correlated with the bond strength between SPUC and steel bars.UPA can effectively improve the mechanical properties of SPUC;however,the in-crease in the concentration of UPA will cause adverse effects on the bond strength between SPUC and steel bars.Therefore,the rational selection of the concentration of UPA and the increase in the amount of reinforcing steel bars are crucial measures for enhancing the reliability of self-protected reinforced under-water concrete projects.