Experimental Study On The Fire Performance Of Post-and-Beam Timber Structure With Bolted Steel-To-Timber Connection

The development of timber architecture in our country has a long history. With the rapid growth of China's economy, the forms of building structure become various. The advantages of environmental-friendly, comfortable and healthy make timber structure popular in the field of architecture. The existing buildings consist of many ancient timber architecture with great value of history and culture. There are many new timber buildings built every year due to the good appearance and mechanical property of timber. According to statistics, the occurrence of building fire disaster presents a tendency of increasing, the fire is of great destructive effects and results in vast of property losses and casualties. Keeping the timber construction from fire is a significant problem needed to be solved. However, the researches concerned with the fire resistance of timber structure are only in the beginning stage in China. Although there are numerous scholars devote themselves to the experimental and theoretical study of timber structure, the achievements could not meet the requirements of application. In the aspect of fire design, the establishments of Chinese norms largely depend on the contents of norms applied in Europe and America. Considering the situation stated above, enhancing the research of fire performance of timber structure is of great significance.In this paper, post-and-beam timber structure with bolted steel-to-timber connection was studied. At first, experiment under standard fire was conducted. Then a simulation of the thermal-mechanical behavior of timber structure was carried out based on ABAQUS. The contents of this paper can be divided into several parts above.(1) The achievements refer to fire performance of timber structures obtained by domestic and alien scholars was concluded.(2) Based on ABAQUS, The method to analyzing thermal-mechanical behavior was used and tested to be accurate by an example of timber connection exposed to fire.(3) Parametric analysis on bolted connection with slotted-in steel plate was conducted by ABAQUS, many factors were considered such as load level, diameter of bolt and edge distance. The results indicate that the increase in load level and bolt diameter leads to the decrease in fire resistance. With a larger edge distance of bolt, the connection shows better fire performance.(4) Experiments on load carrying capacity and fire resistance of post-and-beam timber structure were carried out, the effect of load level and brace was observed. The results indicate that to reduce the load level or add the brace to the specimen are effective accesses to improve the fire resistance. The brace changed the distribution of internal force thus reduce the moment and shear force which retarded the shear failure of the beam.(5) Simulation of post-and-beam timber structure exposed to fire was conducted and the differences between experiment and simulation were compared.(6) Combining the norms of timber structure design domestic and alien, suggestions on fire design were provided. Using the reduced cross-section method, the formulas which guide engineers to calculate the load capacity of timber connections exposed to fire were deduced.