保温模块单排配筋再生混凝土中高剪力墙抗震性能试验研究

Experimental study on seismic behavior of mid-rise recycled aggregate concrete shear wall with insulation blocks and single layer reinforcement

对2个剪跨比为1.5的模塑聚苯乙烯保温模块单排配筋再生混凝土中高剪力墙足尺试件进行拟静力试验,其中1个带保温模块和面层砂浆,1个不带保温模块和面层砂浆。分析了2个试件的破坏特征和抗震性能,并与同类型低矮剪力墙试件(剪跨比为1.0)进行了对比。基于软化拉压杆模型,考虑面层砂浆贡献,建议了保温模块单排配筋复合剪力墙受剪承载力计算模型与公式。研究表明:保温模块及面层砂浆能有效提高墙体的承载力及弹塑性变形,显著提高墙体抗震耗能能力;剪跨比对墙体抗震性能及破坏形态有较大影响,小剪跨比墙体破坏时表现为腹板主斜裂缝出现后,翼缘底部出现剪切斜裂缝的剪拉型破坏,较大剪跨比墙体破坏时表现为腹板主斜裂缝出现后,翼缘底部受压破坏的剪压型破坏;采用的保温模块单排配筋复合剪力墙承载力计算模型及计算式,其计算值与实测结果符合较好,可用于该剪力墙斜截面受剪承载力计算。

Quasi-static tests of two full-scale shear wall specimens with shear-span ratio of I. 5 were conducted under low reversed cyclic loading. One specimen was a single layer reinforced recycled aggregate concrete shear wall with expandable polystyrene （EPS） insulation blocks and mortar layer, while the other one without insulation blocks and mortar layer. Failure feature and seismic behavior were analyzed and compared with the low-rise shear wall （shear- span ratio is 1.0）. Based on softened strut-and-tie model and taking mortar layer into consideration, shear capacity calculation model and formula of single layer reinforced recycled aggregate concrete shear wall with insulation blocks were suggested. The conclusions are drawn that insulation blocks and mortar layer can improve load-carrying capacity and elasto-plastic deformation effectively, especially seismic energy dissipation capacity. Shear-span ratio has a great influence on the seismic behavior and failure feature of shear wall. Shear wall with lower shear-span ratio shows shear- tensile failure with web main diagonal crack and shear oblique crack at the bottom of the flange. While shear wall with higher shear-span ratio shows shear-compression failure with web main diagonal crack and crushing of concrete at the bottom of the flange. The suggested shear bearing capacity calculation model and formula, with the calculated results fit well with the measured results, can be used for the shear bearing capacity calculation of the composite shear wall.