Analysis On Seismic Performance Of Masonry Structure With Partial Rc Frame And Partial Masonry In Bottom

Masonry structure with RC frame and masonry in bottom is widely used in the street construction in undeveloped medium and small cities, especially in the towns under county-level in China. Such structures are damaged seriously in Wenchuan Earthquake, however, corresponding seismic requirements of such structures are not provided in Code for seismic design of buildings, and its seismic performance needs more study. So as a type of masonry structures, its seismic performance and seismic calculation method should be studied urgently. This paper studies the seismic performance on masonry structure with RC frame and masonry in bottom, and draws some conclusions as below:â‘ Earthquake damage and seismic performance comparisonThe contents for comparison include the earthquake damage, elastic earthquake responses and elasto-plastic earthquake responses among these 3 kinds of structures: the masonry structure, masonry structure with bottom RC frame and the masonry structure with RC frame and masonry in bottom. Analysis shows that the seismic calculation method for masonry structure with partial RC frame in the bottom can use base shear method; if there are only single row of columns, it can be designed as masonry structure because the drifts and energy dissipation characteristics are similar with masonry structure; if there are double rows of columns, it needs special design for the differences among them.â‘¡Elasto-plastic analysis of seismic performanceAfter designing this kind of structure according to current Code for seismic design of buildings, the response of displacement and strain of typical masonry structure with RC frame and masonry in bottom under 6 degree and 7 degree major earthquake (two natural waves and one artificial wave input) are analyzed, and the performance level of this kind of structure is evaluated with different performance indexes. Research shows that: masonry structure with RC frame and masonry in bottom can satisfy the seismic fortification request of repair with strong earthquake in 6 degree major earthquake; masonry structure with RC frame and masonry in bottom can satisfy the seismic fortification request of no Ccollapsing with strong earthquake in 7 degree major earthquake.