钢筋混凝土墩柱等效塑性铰长度研究

Research on Equivalent Plastic Hinge Length of Reinforced Concrete Bridge Column

为研究钢筋混凝土墩柱等效塑性铰长度，整理了154根钢筋混凝土墩柱试验数据，研究了墩柱等效塑性铰长度随侧向位移的变化规律，通过试验对各国主要塑性铰长度计算公式进行了对比。讨论了影响墩柱等效塑性铰长度的主要因素，通过回归分析建议了等效塑性铰长度计算公式并进行了验证。结果表明：钢筋混凝土墩柱等效塑性铰长度随位移延性系数变化而变化，但未呈现一致变化规律；与试验结果相比，各公式计算的墩柱等效塑性铰长度离散性均较大，Priestley建议公式在平均意义上与试验结果最为接近，Paulay公式、Panagiotakos公式和欧洲Eurocode8规范公式偏于不安全，中国《公路桥梁抗震设计细则》（JTG/TB02—01-2008）建议公式偏于保守，日本JRA规范建议公式最为保守；钢筋混凝土墩柱等效塑性铰长度主要与试件高度、截面宽度和纵筋直径有关，与纵筋屈服强度、试件轴压比、配箍等因素关系不大；建议的钢筋混凝土墩柱等效塑性铰长度计算公式在平均意义上与试验结果基本一致，适用于剪跨比在2．0～8．0之间且混凝土抗压强度在20～110MPa之间的普通及高强钢筋混凝土墩柱。

In order to study the equivalent plastic hinge length of reinforced concrete bridge columns, 154 test data of reinforced concrete bridge columns were collected. Firstly, the relation between the plastic hinge length and lateral displacement of the column was studied. Then. calculated expressions of the plastic hinge lengths of various countries were compared and main factors of the effects of different variables on the plastic hinge lengths were discussed. At last, based on regression analysis, expression of the plastic hinge length of the column was proposed and the expression was proved by test results. Results show that the plastic hinge length varies with the displacement ducti test results, existing formu ity factor but ae show cons column while the formula proposed doesn＇t present any obvious regularity. Compared with iderable scatter in estimating the plastic hinge length of by Priestley has good agreement with test results on average significance. These expressions proposed by Paulay, Panagiotakos and Eurocode 8 overestimate the plastic hinge length of the column while the proposed expression of code JTG/T B02-01 2008 gives conservative results and the proposed expression of the code JRA is most conservative. The plastic hinge length of the column mainly depends on the specimen length, section width and the diameter of longitudinal steel and is independent of yield strength of the longitudinal steel, axial load ratio and transverse reinforcement ratio of the specimen. The proposed expression for plastic hinge length of reinforced concrete column on the basis of regression analysis shows good agreement with test results on average significance and the expression can be used for concrete bridge column with aspect ratio between 2. 0 and 8. 0, concrete compression strength is between 20 MPa and 110 MPa.