保护层厚度对构件断裂影响的数值模拟研究

Numerical Approach to the Influence of the Protective Layer Thickness on the Mechanical Properties of the Reinforced Concrete Beam

应用材料破坏分析软件MFPA2D(Material Failure Process Analysis)系统,模拟了钢筋混凝土材料在4点弯曲状态下的破坏过程,重点研究了钢筋保护层厚度对钢筋混凝土梁力学性能的影响。研究结果表明:一味地增加保护层的厚度会使梁的截面有效高度减小,从而使构件的承载能力下降。所以要选择适当的保护层厚度,使构件能最好地发挥它的性能。通过本研究发现,一般情况下钢筋保护层厚度在90 mm以内都是比较合理的,但在此前提下仍需要根据相关标准及规范来确定。

In this paper, the system of MFPA （Material Failure Process Analysis） is utilized to simulate the failure process of the reinforced concrete member under the situation of four-point bending. The influence of the protective layer thickness on the mechanical properties of the reinforced concrete beam is mainly researched. The results indicate that the increase of the protective layer thickness will reduce the sectional effective height of the beam, which decrease the hearing capability of the member. Therefore, choosing the protective layer thickness properly will make the member has better properties. In this research, it is also found that generally it is more reasonable when the protective layer thickness is less than 90 mm. However, it is necessary to be confirmed by the relevant specifications and standards.