Load Bearing Behavior Experiment And Finite Element Analysis Of Timber Concrete Composite Structure

Timber concrete composite structure which is abbreviated as TCCS is a new type of composite structure.It is widely used in Germany and other European countries.From the beginning of the 20 th century,TCCS has been paid more and more attention by experts and scholars all around the world,but TCCS has less research and theoretical analysis than other combinations.Based on the TCCS which is widely used in European countries,the combined performance of timber beam and cast-in-place concrete slab is studied.The main works are:(1)Six timber column-concrete short column test pieces were designed.The connection between the timber column and the concrete was connected with 12×120mm bolts.There were two types of bolts,namely,one for right vertical and one for 45 °.The bondability between the column and the post-embedded concrete is studied,and the relative slip and bond ultimate bearing capacity are analyzed.The results show that the ultimate bearing capacity of the 45 °oblique arrangement bolt and the right angle vertical arrangement bolt is basically the same,but slip amount of the former is less than the latter amount.Compared with the lightweight concrete,the ultimate bearing capacity of the wooden column-normal weight concrete is obviously higher than that of the wooden column-light weight concrete.(2)Based on the practical engineering application,a composite structure of timber beam-timber board and 7 timber beams-reinforced concrete slab were designed.The quantity of timber beam is three and they are connected with timber or reinforced concrete slabs through connectors.Through the vertical multi-point static loading test,the common law of the beam-plate structure and the general rule of the distribution of the bearing capacity are studied.The factors such as the distance between the lightweight concrete ? the normal weight concrete,and the distance of the connection in TCC are analyzed.The influence of the bearing capacity on the bending deformation of the beam?the stress changes of the beam andplate structure are discussed.The results show that the combined action of the beam-reinforced concrete slab composite beam and plate structure is stronger and the bearing capacity is uniform and its value is larger than that of the timber-beam structure.Compared with the concrete,the interaction between the beam and the beam is reduced,and the bearing capacity of the composite beam-plate structure is improved when the other conditions are the same.In addition,when the distance of the connection is 120 mm,the interaction of the wood beam-reinforced concrete slab composite beam and plate is stronger and the bearing capacity is higher.(3)The finite element analysis software ATENA was used to model and analyze the structure of the timber beam-reinforced concrete slab.The results show that the experimental results agree well with the finite element analysis results,and the effectiveness of the finite element analysis method is explained.Then,24 finite element models are established.By changing the distance between timber beams,the span of wood beams and the loading position,the common performance of such structures and the general rules of bearing capacity change are studied.The results show that when the spacing of wood beams decreases and the number of timber beam increases,the co-working between the beams and beams of reinforced concrete beams is enhanced and the bearing capacity is increased.When the loading position of the area load is changed from the middle wood beam to the edge wood In this paper,the co-working ability of this kind of structure decrease,and the degree of weakening is increased when the span of wood beam increases,and the tensile stress between the edge beam and the reinforced concrete slab is not loaded.