【作者】 陈志新；

【导师】 邵旭东；

【作者基本信息】 湖南大学 ， 桥梁与隧道工程， 2010， 硕士

【摘要】 全无缝桥梁取消了桥梁伸缩缝,梁体的温度变形由台后的加筋接线路面来吸纳。加筋接线路面一般由基层+连续配筋层+沥青混凝土面层组成。在温降作用下,无缝桥加筋接线路面处在最不利的受拉状态,此时,梁体的变形转化成了连续配筋层中的若干条微小裂缝；在温升作用下,梁体的变形依靠加筋接线路面的弹性压缩予以吸收。本文以无缝桥带预压缝的加筋接线路面为研究对象,做了如下工作：(1)介绍了目前无缝桥梁在国内外的研究概况,并在湖南大学桥梁工程研究所研究的无缝桥梁加筋接线路面的结构形式上加以改进,即在接线路面连续配筋层引入预压缝,并且阐述了这种带预压缝的加筋接线路面的结构形式和优点。(2)研究了带预压缝加筋接线路面在温降作用下的受力特点和变形吸纳方式,建立起加筋接线路面的力学计算模型。推导了带预压缝加筋接线路面在受拉状态下的裂缝计算公式,并编制了相应的配筋计算程序。(3)设计了带预压缝加筋接线路面的节段模型试验,通过对接线路面板模型的拉伸来模拟加筋接线路面在温降作用下的受拉状态。试验结果表明：带预压缝的加筋接线路面在温降作用下产生的裂缝能在预压缝处开裂发展,大大减小了加筋接线路面裂缝的离散性,并且裂缝宽度的实测值与理论计算吻合较好,验证了加筋接线路面裂缝推导公式的正确性。(4)全无缝桥梁实际是一个主梁、搭板和加筋接线路面三者相互作用结构体系,因此对无缝桥梁施工提出的更高的要求。本文根据无缝桥梁的自身结构特点,总结了无缝桥梁中各部分的施工要点。更多还原

【Abstract】 The expansion joints are canceled in the Jointless Bridges, while the thermal deformation produced in the superstructure can be absorbed by the reinforced approach pavement located behind the abutment, which consists of the base, the continuous reinforced layer and the asphalt concrete cover. Once the ambient temperature decreases, the reinforced approach pavement will have to bear an unfavorable tensile stress, in this case, the contraction generated in the main girder finally turns into some random slight cracks in the continuous reinforced layer. While in the opposite condition, the extension produced in the main girder ultimately results in the elastic compression of the continuous reinforced layer. In this dissertation, the following items are presented:(1) Recent accomplishments in the research of Jointless Bridges at home and abroad are introduced. Based on the reinforced approach pavement proposed by Bridge engineering institute of Hunan University, an improvement is presented, which introduces pre-compaction seams into the continuous reinforced layer.(2) An analytical model is developed, which perfectly describes the mechanical performance of the reinforced approach pavement suffered from ambient temperature drop. And formulas are derived to figure out the width of the cracks generated within the reinforced approach pavement implanted with pre-compaction seams. Furthermore, a program is developed to determine the required steel bars for the reinforced approach pavement to bear the thermal loads.(3) A scale model test is conducted, in which the mechanical behavior of the reinforced approach pavement suffered from ambient temperature drop is simulated by axial extension of the model. The experimental results manifests that most of the induced cracks emerges right by the pre-compaction seams, which means that the randomness of them are enormously eliminated. At the same time, the measured values of the width of the induced cracks perfectly agree with the values given by the proposed formulas, it means that the formulas recommended by the author are valid and applicable.(4) As the jointless bridge is a complicated system, in which the main girder, the approach slab, and the reinforced approach pavement interact with each other, it sets higher requirements for the construction procedure. Some key points of the construction technology, which deserves the attention of engineers, are summarized in this dissertation.更多还原