A Study On The Aseismic Capacity Of‘Qiuzhi Building’with Masonry Structure In Bailu Middle School

Structural form of Primary and Middle School buildings is still themasonry structure at a majority of areas in our country.The aseismic capacityof this kind of structure is directly related to the life safety of thousands ofteachers and students.While, the wall percentage of the teaching building withmasonry structure is lower than that of ordinary masonary structure because ofits large structual space. Because of unreasonable structural measures andetc.,it performs badly in many previous earthquakes and is damaged seriouslyin the earthquakes of the same intensity compared with other ordinarymasonry structures.The bad present situation has caught the attention of thesociety and therefore a study on its earthquake damage mechanism and theimprovement of its aseismic capacity are imperative.In the field reconnaissance of Bailu Middle School,it was found that thefront building and the back building of Bailu Middle School were in the samesite and with the same intensity,but performed significantly differently underWenchuan8.0Earthquake although they were only tens of meters away fromeach other.The ‘Qiuzhi Building’(namely Junior Middle Department of BailuMiddle School) damaged severely,while the ‘Qinxue Building’(namelyPrimary Department of Bailu Middle School) was basically well even ifuplifted nealy three meters as a whole.It is shown that the quality of masonrystructure desigh directly affects its aseismic capacity.At the same time,it isfound that although the front building is a kind of masonry structure,yet itsfailure mode is different from other ordinary masory structures’.The seriouslydamaged position of the front building is not in the first storey but in the thirdstorey.The ‘Qinxue Building’ is a masonry structure of4storeys.And itslongitudinal walls of the1stand2ndstoreys are370mm thick,the3rdand4thstoreys are240mm thick.Therefore the seriously damaged position of thebuilding is in the structural vertical transfer storey——the3rdstorey.As awhole,the aseismic capacity and failure mechanism of the masonry structurewith vertically variable stiffness deserves as well as the aseismic capacity ofordinary masonry structure with vertically invariable stiffness become thefocus to be studied.Based on the earthquake damage survey and the field frequency test as wellas finite element simulation, damaging phenomenon of ‘Qiuzhi Building’ inBailu Middle School is summarized. Practical significance is obtained bycomparative analysis of numerical simulation results and earthquakedamage.They are the two listed as follows:1. Damaging phenomenon of ordinary masonry teaching building is briefly summarized and analyzed.2. The aseismic capacity of some kinds of masonry structure with differentlongitudinal wall thickness is analyzed through the finite element model of thekind of masonry structure created by ABAQUS software.And then the failurefeatures and earthquake damage mechanism as well as the aseismic capacityof the masonry structures with vertically variable stiffness and the masonrystructure with vertically invariable stiffness are summarized.