在循环负荷下对加强UHPC-NC复合梁的疲劳行为进行实验研究
Jue Wang1,2, Wenyu Ji1, Wangwang Li3
1School of Civil Engineering and Architecture, Beijing Jiaotong University, Beijing 100044, China.
Materials (Basel, Switzerland)
|April 9, 2024
概括
这项研究研究了钢筋超高性能混凝土 (UHPC) 和正常强度混凝土 (NC) 复合梁的疲劳性能. 研究结果揭示了UHPC层厚度和负载水平如何影响疲劳寿命和降低度.
科学领域:
- 土木工程 土木工程是指土木工程.
- 材料科学 材料科学 材料科学
- 结构工程 结构工程
背景情况:
- 超高性能混凝土 (UHPC) 提供卓越的机械强度和耐久性,导致其在建筑中的使用增加.
- 在拉力区使用UHPC的复合梁和在压缩区使用正常强度混凝土 (NC) 的复合梁 (UHPC-NC梁) 提供了优化的曲系统.
研究的目的:
- 为了研究加强的UHPC-NC复合梁的疲劳行为.
- 分析UHPC层厚度和疲劳负荷水平对疲劳寿命,接口变形和曲刚性的影响.
- 开发一种用于循环负荷下降硬度的预测模型.
主要方法:
- 在循环负荷下对9个加强的UHPC-NC复合梁进行实验测试.
- 超高压PC层厚度的系统变化 (0, 200, 360毫米),强化比率 (1.184%, 1.786%) 和上层负载水平 (0.390.65) 的系统变化.
主要成果:
- 观察到UHPC和NC层之间的结合非常好,在最终疲劳失败之前没有分层.
- 复合体梁的曲刚度在循环负荷时呈现出明显的三阶段减速模式.
- 为了预测UHPC-NC复合梁的刚性降低系数,制定了一种新的方程.
结论:
- 增强的UHPC-NC复合体梁表现出强大的疲劳性能与良好的接口粘合.
- 这项研究为这些复合结构在疲劳条件下的刚性降解机制提供了宝贵的见解.
- 拟议的方程为工程师提供了一个实际的工具,可以预测和管理UHPC-NC复合梁的长期性能.
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