The Study On The Appraisal And Strengthening Of Multi-Story Masonry Buildings After Earthquake

Our country,located in the intersection regions of circum-Pacific seismic zone and Eurasia seismic zone,is one of the countries with the most serious earthquake disasters in the world.The most important means through which the earthquake cause the lose of life and property is the breakage and collapse of buildings.Masonry tier building is a kind of structure form used vastly and extensively in our country.At the same time,the seismic damage of masonry structure is the most severe in the history.So it is significant to study the seismic appraisal and seismic strengthening of the post-earthquake multi-story masonry buildings.The major analysis and research work in this thesis can be concluded as follows:1.Safety assessment in post-earthquakefield(seismic quick appraisal).In the emergency phase after earthquake,it is suggested to carry out urgent structural evaluation on the damaged buildings promptly.lt is necessary to evaluate the earthquake damage condition,the seismic fortification condition and the surrounding environment,confirm the security of buildings quickly and then give the suggestion for disposal.To evaluate the earthquake damage condition,the fuzzy synthetic evaluation method of building earthquake damage in post-earthquake field is established and the weight of each evaluation index is determined by AHP, which resolves the decision model of this complicated system with multi-factors,multi-layers,qualitative nature and fuzziness.It also makes the conventional evaluation method of building earthquake damage which based on the expertise experiences more scientific.2.Seismic appraisal.In the post-disaster reconstruction phase, it is necessary to carry out seismic appraisal on the buildings with a long term usage.The basic concept and content of seismic appraisal are introduced briefly.Then the method about seismic appraisal of masonry tier buildings is introduced comprehensively.3.Seismic strengthening of buildings.The corresponding seimic strengthening methods should be chose according to the different conditions including the shortage of anti-seismic bearing capacity, the shortage of integrity of construction,the local vulnerable part and the distinct torsional effect.In many seimic strengthening methods,masonry strengthening with mortar splint is an effective method which has the function to improve the seismic behavior of walls,and is superior to the other seimic strengthening methods.So it is widely used in the post-earthquake strengthening projects.4.Example of technical application. To explain the engineering application of safety assessment in post-earthquakefield, the actual process and method about it are introduced comprehensively,which are combined with an engineering case and are on the background of 2008 Panzhihua 8.30 earthquake.To explain the technical application of seismic appraisal and seismic strengthening,the technologies of seismic appraisal and seismic strengthening are used on a masonry tier teaching building,which can provide references for other engneering projects.