沙漠砂混凝土框架结构抗震性能及设计方法研究

The contradiction between supply and demand of construction sand is increasingly prominent, and the location of Xinjiang is remote, and transportation cost of construction materials is much higher than its own price. Therefore, the method that using part of the desert sand instead of construction sand to make-up desert sand-concrete is proposed. In this research, the desert sand-concrete is made-up to meet the engineering requirements by adjusting the water-cement ratio, the amount of sand, water reducing agent content, and so on. Meanwhile, seismic design of desert sand concrete frame structure is established by seismic experiment study. The main study content: the formula of desert sand-concrete compressive and tensile strength are established, and the constitutive relation of concrete desert sand is determined by mechanical properties research on desert sand concrete. The mechanism and seismic behavior of desert sand concrete beams, columns, and joints are established by seismic experiment study on desert sand concrete beams, columns and joints. Finally, the seismic mechanism of desert sand concrete frame structure is revealed, and the earthquake damage of structure description criterion is proposed, and the design method and seismic construction measures of desert sand concrete frame structure are proposed by the pseudo static test. In this study, the sand desert sand will replace the engineering sand, which not only effectively relieves the contradiction between supply and demand of coarse, medium sand, but also make full advantage of the rich resources in Xinjiang Corps. Therefore, it will have broad application prospects in xinjiang corps.

针对建筑用砂供需矛盾日益突出的社会现象，以及新疆地处偏远，建筑材料运输成本较高的特点，提出利用部分沙漠砂代替建筑用砂作为基础工程材料的方法。本研究项目拟通过调整水胶比、沙漠砂掺量、减水剂掺量等因素，配置满足工程要求的沙漠砂混凝土，并通过沙漠砂混凝土框架结构的抗震试验研究，建立该框架结构的抗震设计方法。研究内容：通过开展沙漠砂混凝土的力学性能研究，确定沙漠砂混凝土的本构关系，并提出适用于沙漠砂混凝土抗压、抗拉强度的理论计算公式；然后，通过沙漠砂混凝土梁、柱和节点的抗震性能研究，揭示各构件的受力机理和抗震性能；最后通过拟静力试验，揭示沙漠砂混凝土框架结构的抗震机理，提出结构的地震损伤性态描述准则，以及沙漠砂混凝土框架结构的设计方法和抗震构造措施。本研究将沙漠砂代替工程用砂作为基础工程材料，不仅有效缓解粗、中砂的供需矛盾，而且充分利用了新疆沙漠砂的丰富资源，在新疆兵团具有广阔的应用前景。

根据因地制宜、就地取材和合理开发利用自然资源的原则，在新疆的建筑工程中用沙漠砂代替工程用砂作为基础工程材料，不仅可以有效缓解粗、中砂的供需矛盾，而且充分利用了沙漠砂的丰富资源。针对此研究项目，开展的主要工作和结论有：(1)开展了沙漠砂混凝土力学性能的试验研究，建立了沙漠砂替代率从10%~100%变化时沙漠砂混凝土的抗压强度、劈裂拉伸强度、轴心抗压强的计算公式，并建立了沙漠砂混凝土应力-应变本构方程和损伤本构方程，为配置C20-C40常用的沙漠砂混凝土提供理论依据。(2) 以剪跨比、沙漠砂替代率、配筋率、配箍率为设计参数，对沙漠砂混凝土梁的力学性能开展了试验研究，揭示了其破坏机理，并建立了适宜于沙漠砂混凝土梁抗弯、抗剪的承载力计算公式，为新疆的沙漠砂在建筑工程中的应用提供理论支撑。(3) 以剪跨比、轴压比、配箍率、沙漠砂替代率和配筋率为设计参数，分别对沙漠砂混凝土框架柱、节点的抗震性能进行试验研究，揭示了沙漠砂混凝土框架柱、节点的破坏机理，并通过分析可知沙漠砂替代率≤60%时，沙漠砂混凝土框架柱、节点具有与普通混凝土构件相似的抗震性能。(4) 理论分析了沙漠砂混凝土框架柱、节点的抗震性能，建立了其承载力计算公式和恢复力模型。(5) 有限元分析了混凝土楼板、轴压比和配箍率对沙漠砂混凝土框架结构抗震性能的影响，为沙漠砂混凝土框架结构的抗震设计提供了理论依据。