摘要
FRP织物约束方形混凝土柱可以提高其强度和延性,但提高幅度相对于圆形截面柱较小,主要是由于截面形状以及FRP在方柱拐角处应力集中的影响。在国外关于FRP约束方柱的试验研究基础上,对截面形状、约束强度及刚度、拐角应力集中以及强约束临界点等参数进行分析,并根据约束混凝土的强度和应变分别为荷载路径的无关量及相关量,提出新的简化两段线———抛物线、直线轴向平均应力-应变模型。该模型考虑了上述影响参数,并与相关试验数据进行比较分析,结果表明简化的轴向应力-应变模型与试验数据吻合较好,其结构形式简单,参数取值方便。
The strength and ductility of square concrete columns confined by FRP wraps can be improved, but are very limited compared to columns with circular section owing to the section shape and the stress concentration of square column corners. Based on many overseas experimental researches conducted concerning square columns confined by FRP,the section shape, confining strength, stress concentration of corners and critical value of strong confinement are analyzed。According as the stress and strain of confined concrete are considered to be relevant to its loading paths or not,the simplified model of average axial stress-strain, which consists of a parabola and a dash line,is presented。The model of stress-strain considering those parameters is compared to experimental data, and the results show the model has good agreement with experimental data and simple formula,and its parameters are available with ease.
出处
《建筑科学》
北大核心
2005年第2期12-16,共5页
Building Science
