Researches On Lateral Stiffness Of Wall Segment And Seismic Analyses Of Masonry Structures

Concerned research on the material reformation in masonry structure in our country, This paper studies earthquake protective and reduction with new material in masonry structure. This researches are carried out with the support of natural science fund of Shanxi province(20051053).In this paper, the researching and developing situating at home and abroad on seismic properties of the masonry structures are reviewed.As for wall segment with no holes, formulas of equivalent lateral stiffness of storey walls segment are derived from theoretical analyses of influences of rotation angle in the end, and influence factorαof rotation angle is put forward. Furthermore, the idiographic formula ofαis derived from the assumption of separate walls subject to horizontal force in the form of equal or reverse triangle load along height. Based on above researches, some practical charts are given to calculateαof wall segment. Finally a practical example is calculated and results of different methods are compared. Researches show that the method put forward in this paper is more exact than the traditional method in seismic design code, and the precision of the method can satisfy the requirements of the seismic design much more, so it is fit for simplified analyses.In the meantime, on the basis of theoretical analyses of influences of rotation angle in the end, Influence factor of the equivalent lateral stiffness of wall segments of separate walls with holes is analyzed, and practical value of Influence factor with holes is proposed. It is proved through anexample.In this paper, the internal force with earthquake and some vital issues in masonry structure component are studied, It is analyzed the influence of wall with flanges to the wall internal force, and pointed out the effect of wall with flanges should be comprised when calculating of bending moment in the walls. Through an engineering example analysis, it is concluded that the wall beam has effect on the internal force of wall at the both sides, especially for the bending moment in the walls. It is shown that the moment in the walls is increased as the ratio about length of wall with hole and height of wall beam in masonry structure increased. In addition, high-wide ratio and e/h are calculated in this paper, it is concluded that the wall of block masonry is commonly destroyed for shear invalidation with earthquake action and satisfied the requirements of prejudicial press in masonry structure except some wall.