Research And Analysis On Seismic Performance Of Song-style Fourth-grade Timber Frames

The Chinese civilization of 5,000 years of history has a long history.Among them,the ancient Chinese architecture based on wood structure is one of the important components of Chinese culture.China is located between the two major seismic zones in the world.Many ancient buildings have been invaded by hundreds of years of earthquake disasters.The study of the energy dissipation of wood structures in earthquakes is of great significance to the protection of ancient buildings.In this paper,according to the relevant provisions of the Song Dynasty Construction Formula,ABAQUS finite element software is used to establish the fourth-class timber frame model,and the horizontal static loading and ground vibration excitation simulation test and numerical analysis of the timber frame are carried out.The static simulation test of the wooden frame under different vertical weights,including one-way limit reversal and low-cycle horizontal reciprocating test,obtained the hysteretic behavior of the timber frame and various energy data during the loading process.The results show that: during loading The slip and shear deformation of the wooden structure tenon joint will occur,and the overall restoring force and initial stiffness of the frame will increase with the increase of the top weight of the column;In the reciprocating loading test,there are three forms of energy conversion for the input timber frame: friction energy dissipation,elastic deformation energy stored in the structure and gravitational potential energy.Among them,the increase of gravitational potential energy due to component uplift accounts for a larger proportion,which constitutes an important part of the total energy conversion process.The quasi-static simulation test of double-span timber frame under different vertical counterweights is carried out.The bearing performance and energy conversion of single and double-span timber frames are compared.The results show that the bearing capacity of the double-span frame is stronger than that of the single-span timber frame;the conversion form of input energy in a doublespan structure is the same as that of single-span structure.The double-span structure has more frictional energy than the single-span structure due to more nodes,the ratio of the gravitational potential energy increased by the component uplift is the largest,.The gravitational potential energy plays an important role in the function of the structure to achieve energy dissipation.The dynamic simulation experiment of the wooden frame model with different weights is carried out,and natural vibration period of wood structure was determined by simple harmonic excitation test,the ground motion excitation simulation test was carried out on the structure under the condition of resonance,and the dynamic response results of the wooden frame under the excitation of three kinds of seismic waves are compared.The results show that when the characteristic period of ground motion is close to the natural vibration period of the structure,the structure has a large response to the displacement;the acceleration response of the timber frame at different measuring points increases with the increase of seismic wave excitation intensity;the damping of the tenon joint of the ancient building is more effective when the seismic excitation intensity is large.