基于内聚单元模型的装配式剪力墙数值模拟研究

Numerical investigation of hysterical behaviors of assembled shear wall based on cohesive element model

随着我国预制装配式结构的推广,装配式剪力墙结构在我国的高层住宅中取得了广泛应用。目前对装配式剪力墙结构的设计采用了"等同现浇"的理念,没有考虑到现浇剪力墙与装配式剪力墙的差异性。在实际工程中。装配式剪力墙普遍通过灌浆套筒进行连接,具体为竖向钢筋在套筒内通过浆锚粘结,剪力墙底部与基础通过一层20 mm厚的高强灌浆料粘结。实际上,灌浆套筒的存在改变了钢筋的刚度分布,而灌浆缝的存在构成了剪力墙的初始薄弱部位,这些因素都对构件的整体力学性能有一定的影响。为了研究装配式剪力墙的整体非线性行为,本文开展了数值模拟研究。基于ABAQUS平台建立了预制装配式剪力墙的精细分析模型,采用损伤模型追踪墙体混凝土的损伤和开裂,引入内聚单元模型模拟剪力墙的水平拼缝。在考虑了上述因素之后,数值模拟结果与实验符合良好。基于数值模拟结果研究了装配式混凝土剪力墙的滞回耗能、损伤开裂以及钢筋应力重分布等细节,对预制装配式剪力墙结构的抗灾性能给出了综合评价。

With the promotion and application of fabricated structures,the fabricated shear wall structure has be widely used in the high-rise residential building structures in China.At present,the differences between cast-in-place shear wall and the fabricated shear wall has not been well considered in the structural design.The connections between the precast shear walls are based on grouting sleeve and cohesion seal,which is a layer of 20 mm thick high-strength grouting material.Technically,the imbedded grouting sleeves and the cohesion seal change the stress redistribution of the precast specimen very much when subjected to horizontal loads.In the present work,the refined finite element model is developed based on ABAQUS for the numerical investigation of the fabricated shear wall.The damage cracking of concrete wall is modelled by the damage constitutive model,and the cohesion seal is modelled by the cohesive elements.The numerical results agree well with the experiment results.And the numerical investigations show the hysterical behaviors,energy dissipation,cracking and damage of concrete,and stress redistribution of steel bars.This work also places an assessment of disaster resistance performance for the fabricated shear wall structures.