摘要
在冲击、爆炸等强荷载作用下,钢筋混凝土结构通常是发生弯曲破坏。室内外试验结果表明,当动荷载峰值较大、作用时间较短(脉冲荷载)时,钢筋混凝土结构易发生脆性的剪切破坏,其主要原因是脉冲荷载的高频成份丰富和加载速率高等特点容易激发结构构件中的剪切变形和剪应力。本文基于Timoshenko梁理论,提出了一种爆炸荷载作用下钢筋混凝土梁破坏形态的有限差分预报方法,利用该方法分析了荷载加载速率、截面高度、混凝土强度、配筋率等对钢筋混凝土梁破坏形态的影响规律,并指出,随着荷载升压段加载速率、截面高度、主筋配筋率的增加或混凝土强度的降低,梁的破坏形态从弯曲破坏转变为剪切破坏。
The flexural failure is usually observed in the reinforced concrete structure under the blast loadings induced by impact and explosion. However, it is shown that the brittle shearing failure is likely to happen in the reinforced concrete structure when it is subjected to the impulsive loading. The reason is that the properties of high frequency and high loading rate of the impulsive loadings stimulate the shear deformation and the shear stress in the structural members. Based on the Timoshenko beam theory, a finite difference method for the prediction of the failure mode of RC beams under the blast loading is proposed. The influence of the several factors, such as the loading rate, height of cross section, the strength of concrete and the longitudinal reinforcement ratio, on the failure mode of the blast-loaded beams is investigated by the proposed analytical procedure. It is pointed out that the flexural failure is transferred into the shearing failure with the increase of the loading rate, the height of cross section and the longitudinal reinforcement ratio whereas the shearing failure is transferred into the flexural failure with the increase of concrete strength.
出处
《计算力学学报》
EI
CAS
CSCD
北大核心
2003年第1期39-42,48,共5页
Chinese Journal of Computational Mechanics
基金
国家自然科学基金资助项目(59708013).
关键词
爆炸荷载
钢筋混凝土梁
破坏形态
有限差分法
Blasting
Finite difference method
Loading
Reinforced concrete
Shear deformation
Shear stress
