Research On Seismic Performance Of Step-terrace Masonry Structure By Pushover Method

The mechanical model of step-terrace building structure,the interaction between structure and slope are different from the conventional building structure.Therefore,the dynamic characteristics of mountainous building structures and the response of structures under earthquake action are quite different from those of conventional building structures.However,the research on the mechanism and characteristics of step-terrace structure is mainly aimed at the reinforced concrete frame structure.Step-terrace masonry building is widely distributed in mountainous cities and towns as a mountainous building,but there is no special literature to study its seismic performance.Therefore,it is necessary to expand the related mechanism analysis and Performance Research of step-terrace masonry structure.First,a number of examples of step-terrace masonry structure and corresponding conventional masonry structures are designed.Then,based on Pushover method,using the ABAQUS finite element software to assess their elastic plastic performance of step-terrace masonry structure with rigid foundation assumption.Main conclusions that we draw are as follows:(1)The natural vibration period of step-terrace masonry structure is smaller than that of conventional masonry structure.As the increasing of the number of the off-layer and the off-across,the natural vibration period of step-terrace masonry structure will gradually increase.(2)For step-terrace masonry structure,the interlayer displacement angle and shear force of the upper grounding layer masonry structure are the largest.As the increasing of the number of the off-layer and the off-across,the interlayer displacement angle and shear force of the upper grounding layer masonry structure will increase.The shear force of the longitudinal walls on the upper grounding layer of step-terrace masonry is very uneven: the shear force of the longitudinal wall allocated at the location of “the first grounding wall ” is the largest,and is larger than the corresponding conventional masonry structure;At the “first non-grounding wall” location,the shear force of the longitudinal wall is the smallest.(3)The shear failure of step-terrace masonry structure is the first occurrence of the upper grounding walls between windows or corner bricks,forming a 45 degree crack from the horizontal direction,and the weak layer is the upper grounding layer.(4)The number of the off-layer and the off-across have little effect on the story torsion rotation above the upper grounding layer.As the increasing of the number of the off-layer and the off-across,the story torsion rotation of the upper grounding layer will increase.The story torsion rotation of step-terrace masonry structure on the upper grounding layer is the largest,which indicates that the torsional effect of the upper grounding layer is the most obvious.