新Ⅲ级钢筋动力性能及在抗爆结构中的应用试验

Experimental Research on New Grade 3 Steel bars Dynamic Mechanical Property and Its Application to Blast resistant Structure

摘要:

在静力试验的基础上首先利用KG 5型快速加载试验机对新Ⅲ级钢筋进行了不同应变率下的动力性能试验，完整给出了材料的动态应力时程曲线，定性研究分析了新Ⅲ级钢筋的动态力学性能；然后利用KG 500型快速加载试验机对不同配筋率、不同混凝土强度的梁进行了快速加载条件下的抗弯性能试验，比较研究了新Ⅲ级钢筋与普通II级钢筋混凝土梁的动态抗弯承载性能及其与配筋率及混凝土强度的变化关系.结果表明,新Ⅲ级钢筋具有良好的动态力学性能，随变形速率增加，其屈服强度提高，但塑性保持不变；在防护结构中合理采用新Ⅲ级钢筋具有良好的综合效益.同时指出了在使用中应注意与混凝土强度匹配的具体问题.

Abstract:

Based on the static tensing test, the dynamic mechanical behavior of new grade 3 steel bars (NG3S) with different strain rates was first experimented systematically on the rapid loading test machine of KG 5, the complete dynamic stress time curves of NG3S under high strain rate were given, and the dynamic mechanical properties of NG3S were analyzed based on the test results. Then, through dynamic beam test on the rapid loading test machine of KG 500, the static and dynamic bending bearing capacity of NG3S concrete beams with different reinforcing percents and concrete strengths were studied by experimental method and compared with the beams with ordinary grade 2 steel bars. The result shows that the NG3S materials are of good dynamic properties and its dynamic performance increases with the strain rate, but the plastic property maintains invariable. The adoption of NG3S in protective structure brings a favourable comprehensive benefit. Finally, the key problem was put forward that the NG3S should match with the concrete strength.