钢筋锈蚀对全珊瑚海水钢筋/混凝土柱大偏心受压性能的影响

通过对不同混凝土强度等级、不同种类钢筋的全珊瑚海水钢筋/混凝土柱（CA/CC）进行大偏心受压性能试验，研究了CA/CC的破坏形态、变形和承载力，建立了荷载-位移、荷载-应变等关系，探讨了CA/CC大偏心受压极限承载力（N_u）的计算模型。结果表明:CA/CC的受力破坏机制和形态与普通骨料钢筋/混凝土柱（OA/CC）基本相似。随着混凝土强度等级的提高，CA/CC纵向受拉钢筋应变开始突变所对应的荷载逐渐增大。在加载过程中，有机新涂层钢筋与珊瑚/混凝土（CA/C）之间产生较大的滑移，使在相同混凝土强度下，普钢钢筋CA/CC的N_u比有机新涂层钢筋CA/CC的N_u大约高7.1%~20.8%。建议在CA/C结构中采用有机新涂层钢筋，能有效的抑制钢筋发生锈蚀，从而延长CA/C结构的有效服役寿命。综合考虑钢筋锈蚀和涂层钢筋滑移的影响，提出了适用于满足高强、高耐久性要求的CA/CC大偏心受压N_u计算模型。 

Influence of steel corrosion to the large eccentric compression behavior of coral aggregate reinforced concrete column

The large eccentric compression behavior of coral aggregate reinforced concrete column (CA/CC) with different types of reinforcement and concrete strength grade was tested. The failure mode, deformation and bearing capacity were investigated. The relationships of load-displacement and load-strain were established. The applicable calculation model for ultimate bearing capacity (N_u) of CA/CC under large eccentric compression was suggested. The results show that the compression behavior of CA/CC is similar to the ordinary aggregate reinforced concrete column (OA/CC). With the increase of concrete strength grade, the load corresponding to the sudden change of the strain of CA/CC longitudinal tensile steel gradually increases. In the loading process, a greater slip was produced in the layer between the organic new coated steel and coral aggregate concrete(CA/C). N_u of common steel is approximately 7.1%~20.8% higher than that of organic new coated steel. The application of organic new coated steel in the CA/C structure is suggested to effectively inhibit steel corrosion and extends the effective service life of the CA/C structure. Based on the comprehensive consideration on the effects of steel corrosion and slip of the coated steel, a calculation model for N_u of CA/CC under large eccentric compression is proposed.