Research On Seismic Behavior Of Soil And Wood Composite Structure In Tulou

Fujian province,located in the southeast coast of China,facing Taiwan province across the sea,belongs to the earthquake-prone areas with many strong earthquakes and large earthquakes occurred in history.In rural areas there are many earth architectures in service while the Tulou is a representative of them.Although the Tulou bears reasonable overall structure layout and some anti-seismic protection measures,the anti-seismic performance of existing Tulou is under serious skepticism given that the Tulou has a long history and suffers wind and rain erosion throughout the past years along with limited construction technology.To better protect the Tulou,we must understand the anti-seismic performance and failure mode of Tulou and reinforce its weak point in a timely manner,thus avoiding serious damage caused by earthquake to Tulou.In addition,the special structure of the Tulou is also enlightening for us to study the anti-seismic structures.This paper,based on this background,took the shaking table test as the foundation and employed finite element software ABAQUS to conduct analysis on the Tulou’s unique structural form(earth and wood),working mechanism,mechanical properties and failure modes.(1)Through several times of on-the-spot investigation on Fujian Tulou,the representative circular-type Tulou “Rusheng Building” and square Tulou “Qingfu Building” were selected as the experimental prototype of the anti-seismic table.This paper chose EL Centro wave,Kobe wave,and Shanghai wave as input ground motion,measured the velocity,acceleration and displacement response of the table-board,the middle part of the wall,the upper and the top part of the wall under various seismic excitations and different seismic waveforms,analyzed the model’s natural vibration period,dynamic response as well as failure mode,and utilized finite element software ABAQUS to simulate the experimental model,check with test,and verify the feasibility of the finite element simulation.(2)The Tulou is a composite structure made of soil and wood.This paper,by establishing actual model through ABAQUS software and selecting EL Centro waveas input seismic wave,conducted simulation on the actual model of Tulou,and analyzed the dynamic characteristics and failure form of real Tulou by changing the magnitude of seismic wave’s acceleration,in an attempt to study the anti-seismic performance of the overall structure of the Tulou.Meanwhile,two other factors(the number of holes for windows and doors of exterior wall,the type of seismic wave)were also considered to study their impacts on the anti-seismic performance of the Tulou’s overall structure.(3)In real life,the internal wood structure of Tulou is built by lapped mortise-tenon joints,which do not belong to the rigid joint or hinge joint but a kind of special semi-rigid joint.Under the action of earthquake load,there will be some friction and slip among the joints,which will affect the anti-seismic performance of the whole structure.Therefore,this paper built a reduced-scale model of the Tulou through ABAQUS software,added wood structure inside the reduced-scale model to verify the differences in anti-seismic performance under two conditions the Tulou model bears under consolidation and friction and slip at the joint,and further analyzed the influence of friction and slip at the joint on the anti-seismic performance of Tulou.