【作者】 赵晓艳；

【导师】 田稳苓；

【作者基本信息】 河北工业大学 ， 结构工程， 2004， 硕士

【摘要】 混凝土结构的维修加固已经成为当前工程领域的一项重要内容，所以新老混凝土结合面受力性能的研究对于保证混凝土修补结构的安全性具有深远的意义。 新老混凝土之间的良好结合是混凝土修补成功的关键所在，目前国内外的研究中绝大部分是通过二者的粘结作用使其结合成为整体共同受力。而实际工程中仅仅依靠粘结力往往达不到理想的结合程度。因此，本文研究的是加强新老混凝土结合，弥补粘结力不足的一种新方法，即采用机械连接件将新老混凝土结合在一起的方法。 新老混凝土的粘结实际是弹性模量不同的两种材料——即双材料的结合问题。本文通过数值模拟计算结果表明，在规范规定的修补结构新老混凝土强度等级差值范围内，新老混凝土弹性模量相差不大的情况下，新老混凝土粘结劈拉强度可近似采用整体混凝土劈拉强度计算公式。 进行了新老混凝土结合的劈拉强度试验。对比了老混凝土表面处理相同的情况下，不同浇筑方位对无机械连接件试件劈拉强度的影响；机械连接件对劈拉强度的影响；不同植筋材料对劈拉强度的影响。 分析了不同浇筑方位对劈拉试件强度造成影响的原因以及机械连接件在劈拉加载时的受力机理。 对比相同界面粗糙程度下，机械连接件对抗剪强度的影响；对比在加机械连接件的试块中，界面剂——水泥膨浆的影响；对比各新旧结合试块抗剪强度与整体伴随试块抗剪强度的差别。 通过测量钢筋在受剪时候应变，得出钢筋的荷载—变形曲线，对机械连接件的受力原理做了分析；分析了膨胀水泥净浆作为界面剂时对于试件抗剪强度的增强机理。更多还原

【Abstract】 The repair and strengthening of concrete structure has become an important engineering domain .So the study of adhesive performance of young and old concrete has far-reaching meaning for the security of repaired structure.Where the shoe pinches of the repair success is all right combination of young and old concrete.Presently,most of the researches inside and outside country made the two into one to against force through felt.In practice,however,it can’t obtain ideal bond capacity only depend on adherence.Thus,this paper bring forward a young method to make up the lack of felt capacity-use mechanical joint element to link young and old concrete.In fact,the adherence of young and old concrete belongs to the adherence research work of bimaterial.The simulation calculation shows that in the range of criterion provision of young and old concrete that the formula for calculating the splitting tensile strength of a monolithic concrete specimen can be used to a concrete specimen of young and old concrete when the difference of elastic modulus of young and old concrete is small.The cleavage strength test has been carried out to investigate the effect of pour direction for the strength of specimen without mechanical joint element ;the effect of mechanical joint element for the cleavage strength;the effect of different materials which were used to embedding bars for the cleavage strength. All the interface of specimens we mentioned above had the same roughness.The reasons of different pour direction effects for the cleavage strength has was analyzed,so did the mechanism of mechanical joint element in the cleavage test.In the situation of same roughness interface,compared the shear strength of specimens with mechanical joint element and that of without;Compared the shear strength of specimens with adhesive agent and without adhesive agent when there were mechanical joint element in the specimens. Compared the shear strength of specimensthat was made of young and old concrete and which was monolithic.The load-stain curve of bar was obtained in the shear strength test. The mechanism of mechanical joint element in the shear test was analyzed. Strengthen mechanism of adhesive agent-expand cement paste.更多还原