王晨霞　王宇　李敬红　宋波　曹芙波

摘要：为了探究再生混凝土结构的耐久性能，对5组不同钢筋锈蚀率（0～9%）的再生混凝土梁式试件进行加载试验。分析不同钢筋锈蚀率对再生混凝土梁式试件的钢筋应变、局部粘结应力、粘结滑移和极限粘结应力的影响。结果表明：钢筋锈蚀率大于3%时试件底部开始有细微锈胀裂缝出现；锈蚀率越大，荷载作用下钢筋应变沿锚固位置的变化曲线越平缓；局部粘结应力沿锚固段呈现出双峰分布，峰值主要集中在加载端和自由端附近；加载端附近位置滑移现象最先发生，远离加载端滑移现象延后；随着钢筋锈蚀率的增大，极限粘结强度先增加后降低，极限荷载下的滑移值增大。

关键词：再生混凝土；梁式试件；锈蚀钢筋；粘结滑移

中图分类号：TU375

文献标志码：A文章编号：16744764（2016）01004608

Abstract：

We carried out load testson five groups of recycled concrete beam specimens of different corrosion rates

to explore the recycled concrete structure durability，

The influence of rebar corrosion rate to was studied.

and analyzed the influence of different corrosion rates on

steel bar strain，local bond stress， loadslip and the ultimate bond stress

of recycle concrete beam specimens.

The results show that lightly corrosive cracks appeared in the bottom of the beam when rebar corrosion rate was greater than 3%.The strain curve was flat when the corrosion rate of reinforcing steel bar was greater with the anchor position under the breaking load. The distribution of local bond stress along the anchor section was bimodal distribution， and peak mainly concentrated near the loading end and the free end. The slippage phenomenon happened first on the position near the loading end， and delayed away from the loading end. With the increase of rebar corrosion rate， ultimate bond strength increased first and then reduced and slip value increased under the ultimate load.

Keywords：recycled concrete； beam specimens； corroded steel bars； loadslip

近50年以来，人们对再生混凝土的认识己经从陌生逐渐发展到熟悉，尤其是在发达国家，再生混凝土的研究已经从非结构构件层面转向结构构件层面[1]，再生混凝土已经慢慢扩大了在实际工程中的应用[23]。同时也将面临着耐久性问题，其中，由于氯离子侵蚀引起钢筋锈蚀问题是导致结构粘结耐久性破坏的一个主要因素。

中国对再生混凝土的研究比发达国家起步晚。目前，主要针对再生粗骨料的物理力学性能、再生混凝土材料的耐久性能进行了研究，而关于再生混凝土结构耐久性的研究比较少。由于再生粗骨料在形状、材料性能等方面不同于天然粗骨料以及再生混凝土特殊的界面结构[4]，使得我们不能完全按照普通混凝土技术进行设计、施工。……