Shaking Table Test And Finite Element Analysis Of Seismic Simulation Of Free-standing Stone Cave Dwelling

Cave dwelling is a typical traditional dwelling in the Loess Plateau region of China.It embodies the people’s living wisdom,construction skills,social ethics and aesthetic consciousness in this area.It is our incumbent historical responsibility and glory to reasonably protect and inherit this typical traditional dwelling.The mission also meets the requirements of the national development plan and has important scientific value and significance.At the same time,its rational application is also of great practical significance for solving my country’s current energy and environmental problems.As a typical representative of cave dwellings,free-standing stone cave dwellings are widely used,their seismic resistance is poor for lack of reasonable seismic construction measures and low material strength.At present,domestic and foreign research on free-standing stone cave dwellings are only at the level of building history,ecological energy saving structural damage investigation and numerical simulation,etc.No relevant experimental research has been carried out on the seismic response of free-standing stone cave dwellings.With the support of the Shaanxi Science and Technology Co-ordination and Innovation Project,and under the background of “precision poverty alleviation” and “seismic reconstruction of rural houses in high-intensity areas” across the country,a 1/4-scale three-span free-standing stone cave dwelling model was subjected to a shaking table test to study its seismic response by this article,which provided theoretical support for the seismic safety assessment and reinforcement design of such traditional houses.This paper studies as follows:1.Based on a large number of investigation and research,the typical structural dimensions of the free-standing stone cave dwelling is summed up.Taking a typical freestanding stone cave dwelling in Jingle County,Shanxi Province as a prototype,an under-manual mass scale(1/4)test model was designed and produced according to the similarity law.2.Through the shaking table test of the model structure,the destruction process and destruction form of the free-standing stone cave dwelling under the action of seismic wave were observed,the dynamic characteristics and response law of the model structure were studied,and the torsional effect and energy consumption capacity of the model structure under the earthquake action were analyzed.The results show that the structural damage is dominated by cracking of mortar and mortar joints under strong earthquakes.The model structure has the most severe damage at the vault of the openings of the side tunnels and the legs of the middle kiln.,The cracks in each part are connected to each other,and the dome of the side opening of the model structure and the middle kiln leg are the weak parts of the free-standing stone cave dwelling;the natural frequency of the model structure decreases with the increase of the loading level,The final self-vibration frequency of X direction and Y direction drops to 49.5% and 70.1% of the initial state.The damping ratio increases with the increase of the loading level.The final damping ratio of X and Y directions increases to 4.7 times and 1.9 times of the initial state.Xdirection stiffness degradation is greater than Y-direction;The X-direction and Ydirection acceleration magnification coefficients decrease with the increase of the loading level;comparing the X-direction acceleration response,it can be seen that the response of the cave entrance is stronger than that of the near palm face,The acceleration and displacement response of the middle arch cave is stronger than the side arch cave;the horizontal displacement of each part of the cave makes linearly similar vibration according to the time-history curve of the basic excitation feedback;when the input acceleration peak value is less than 440gal(large earthquake),the maximum lateral displacement of the structure appears on the arch top,and the input acceleration peak value is greater than 600 gal,the structure enters the plastic stage,and the maximum lateral displacement appears on the top of the cave dwelling;the structure exists stiffness eccentricity,and the torsion angle of the model structure under the action of unidirectional seismic waves increases with the increase of the loading level.The maximum torsion angle is 0.0037 rad,and the torsion effect of the structure is more obvious;the energy consumption of the structure increases with the increase of the input seismic wave loading level.3.The finite element analysis software ABAQUS was used to establish an freestanding stone cave dwelling analysis model,and the calculation results are in good agreement with the test results.The whole process of the dynamic damage of the model structure under earthquake action was analyzed,the time sequence and spatial distribution characteristics of the plastic zone of the structure were studied,and the dynamic response law of the model structure under earthquake action was analyzed.The influence of the number of arch span,the ratio of arch span to rise span and the thickness of overburden on the seismic response of free-standing stone cave dwelling is analyzed and studied.