可拆式钢筋桁架模板及其混凝土楼板受力性能试验研究

发布时间：2018-07-01 10:44

本文选题：可拆式模板 + 钢筋桁架　；参考：《西安建筑科技大学》2017年硕士论文

【摘要】：为了达到快速施工、制作工厂化、经济环保的目的,研发出新型楼板体系-可拆式钢筋桁架模板,其利用上下层纵向钢筋与弯折成形的腹杆钢筋焊接,将钢筋桁架与模板通过特制的连接件进行连接。在施工阶段能够承受湿混凝土与施工荷载;正常使用阶段,钢筋桁架作为混凝土板的配筋,能够承担使用荷载。这样既能够保留传统楼板体系的优势,又能够有效地规避其不足之处。最大的优点在于使用阶段可将底部模板拆卸,循环使用多达30次;若未拆卸,可作为吊顶装饰。本文通过20个可拆式钢筋桁架模板静力加载试验,分析挠度变形、钢筋应变随荷载的变化规律,并给出其受力性能的主要影响因素;同时对18个连接件进行抗拉试验,主要研究连接件的破坏特征以及抗拉强度,给出实际工程中连接件的强度设计建议值。在试验的基础上分析可拆式钢筋桁架模板的抗弯刚度,利用采用荷载-挠度曲线法和极限弯矩法进行计算,与理论计算值对比发现,极限弯矩法适宜可拆式钢筋桁架模板的抗弯刚度计算;与此同时建立不同尺寸可拆式钢筋桁架模板抗弯刚度关系,为实际生产检验提供参考依据;本文给出实际工程中施工阶段,简支或连续(两跨)支撑下最大无支撑长度,并提出大跨度下变形较大的解决方案。通过2个钢筋桁架混凝土楼板静力加载试验以及有限元模型分析,研究弹塑性阶段的抗弯性能与影响因素。并对现有的钢筋混凝土极限承载力公式进行修正,提出实际工程可供参考的极限承载力计算公式。采用规范规定和有效惯性矩法分析钢筋桁架混凝土楼板抗弯刚度,与试验值对比后,规范规定方法较为适宜,并提出修正后的抗弯刚度计算公式。
[Abstract]:In order to achieve the goal of rapid construction, factory manufacture, economy and environmental protection, a new type of floor system-removable steel truss formwork was developed, which welded the upper and lower layers of longitudinal steel bar with the web bar formed by bending. The steel truss and the formwork are connected by special connectors. In the construction stage, it can withstand wet concrete and construction load, and in the normal use stage, the reinforced truss, as the reinforcement of concrete slabs, can bear the use load. This can not only retain the advantages of the traditional floor system, but also effectively avoid its shortcomings. The biggest advantage is that the bottom template can be removed during the use phase and recycled up to 30 times; if not removed, it can be used as a ceiling decoration. In this paper, through static loading test of 20 removable steel truss formwork, the variation law of deflection and rebar strain with load is analyzed, and the main influencing factors of its mechanical performance are given, and the tensile test of 18 connectors is also carried out. The failure characteristics and tensile strength of connectors are studied, and the suggested design values of joint strength in practical engineering are given. Based on the test results, the bending stiffness of the removable steel truss formwork is analyzed. The load-deflection curve method and the ultimate bending moment method are used to calculate the bending stiffness. The ultimate bending moment method is suitable for calculating the bending stiffness of the removable steel truss formwork, and at the same time establishing the bending stiffness relation of the different size removable steel truss formwork, which provides the reference for the practical production inspection. In this paper, the maximum unbraced length under simply supported or continuous (two span) brace in the construction stage of practical engineering is given, and the solution of large deformation under long span is put forward. Through two static loading tests of reinforced truss concrete slabs and finite element model analysis, the flexural behavior and influencing factors in elastic-plastic stage are studied. The existing formula of ultimate bearing capacity of reinforced concrete is revised, and the formula for calculating ultimate bearing capacity of practical engineering is put forward. The flexural stiffness of reinforced truss concrete floor slab is analyzed by the method of specification and effective moment of inertia. Compared with the experimental data, the method of specification is more suitable, and the modified formula for calculating flexural stiffness is put forward.
【学位授予单位】：西安建筑科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU755.2;TU37

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