UHPC石墙嵌缝加固的福建典型石结构抗震性能模拟与分析

Seismic Performance Simulation and Analysis of Fujian Typical Stone Structure Reinforced by UHPC Stone Wallinfilled Joints

福建沿海地区石结构民宅保有量大,石结构抗震性能较差.石墙是石结构主要的承重及抗侧力构件,超高性能混凝土(UHPC)嵌缝加固石墙可提高石结构的抗震性能.为探究石墙经过UHPC嵌缝加固后石结构的整体抗震性能,采用LS-DYNA有限元软件分别建立了未加固石墙和UHPC嵌缝加固石墙的两种石结构模型,研究石结构地震破坏全过程,分析结构地震响应、破坏机制和抗震性能.研究结果表明:石结构在地震作用下呈现“竖向倒塌”的破坏模式.在PGA为55gal和110gal的工况下,未加固结构的损伤状态为轻微破坏和整体坍塌;加固后结构的损伤状态分别为基本完好和中等破坏.相比未加固结构,加固后的石结构基本周期略有降低,楼面峰值加速度降低了21.05%~25.26%;位移角减小了74.90%~94.50%,加固后石墙开裂得到有效抑制,结构损伤程度有所减小,加固效果明显.

In the coastal regions of Fujian,there are a large number of residential buildings constructed from stone,and they exhibits poor seismic resilience.Stone walls are the main load-bearing and lateral force resistant components of stone structures.Strengthening stone walls with UHPC infilled joints can improve the seismic performance of stone structures.To explore the overall seismic performance of stone structures after UHPC infilled joints,this study utilized the LS-DYNA finite element software to establish two distinct models of stone structures:one without reinforcement and another reinforced with UHPC infilled joints.The research aimed to investigate the complete seismic failure process,analyzed the seismic response,failure mechanisms,and performance of the structures.Findings reveal that the stone structure exhibits a“vertical collapse”failure mode under seismic action.For PGA of 55 gal and 110 gal,the unreinforced structures exhibited minor to complete collapse,whereas the reinforced structures showed conditions ranging from minor damage to moderate destruction.Compared with the unreinforced structure,the fundamental period of the reinforced stone structure is slightly reduced,the peak acceleration of floor has decreased by 21.05%to 25.26%,and the displacement angle was reduced by 74.90%to 94.50%.The infilled joints reinforcement effectively curtailed stone wall cracking,mitigated structural damage,and significantly enhanced reinforcement effectiveness.