基于ECC的小雁塔抗震加固性能分析

Performance Analysis of Small Wild Goose Pagoda Seismic Reinforcement Based on Engineered Cementitious Composite

高延性纤维增强水泥基复合材料(ECC)是一种高强度、高延性的新型建筑材料,在加固工程中具有广泛的应用前景。本文利用ECC的高延性和抗剪性,提出一种采用ECC面层加固小雁塔的保护方案,以提高古塔抗震性能;通过有限元软件ANSYS进行模拟分析,比较了小雁塔加固前后的地震响应。分析结果表明:采用ECC面层加固可显著增强塔身整体的延性和承载力,有效地提高塔体损伤容限,为ECC在古塔抗震加固的实际应用中提供借鉴,可作为古塔抗震保护的新途径。

Engineered cementitious composite(ECC),a new type of building material possessing high strength and excellent ductility,presents wide application prospects in strengthening engineering.This thesis takes advantage of these characteristics of ECC to put forward a protection scheme using ECC surfaces to reinforce the Small Wild Goose Pagod and improves its seismic performance of ancient pagoda.Using the finite element software ANSYS,the full size of the Small Wild Goose Pagoda is modeled via a monolithic masonry model.According to the national standard Code for Design of Masonry Structures and referencing the actual condition of the pagoda,the degree of damage to its bricks,and the multilinear kinematic hardening model,the uniaxial stressstrain curve of the masonry is adjusted.The damage criterion of materials is further defined using five Willam-Warnke parameters.The El Centro seismic wave is selected as the ground motion input,and three levels of amplitude modulation are adopted.The maximum acceleration values of the three conditions are70,220,and400gal.The seismic response of the model was analyzed using dynamic timehistory analysis methods,and the maximum displacement and acceleration of each layer are extracted.The story drift is also calculated.The criteria show that the pagoda is seriously damaged to the brink of collapse when the peak earthquake acceleration is400gal.The earthquake response of the pagoda notably decreased after establishment of the ECC reinforcement model of the Small Wild Goose Pagoda.The analysis results demonstrated that the ECC surface layer reinforcement can significantly enhance the overall ductility and bearing capacity of the tower,effectively improving its damage tolerance.This work provides a reference for the practical application of ECC in ancient tower seismic reinforcement for earthquake protection.