Test Study And Mechanical Analysis On Frame-supported Multi-ribbed Composite Wall Beam

With economical development and living standard's improvement, houses with commodious space at the first storey(s) are widely spread during the last two decades. So far in China, the main form is Lower Frame-Shear Wall Structure with Upper Masonry Structure (LFSWSUMS). However, due to masonry structure's high self-weight and low aseismic capacity, the total height of the building and the number of storeys are strictly limited. On the other hand, masonry structure's industrial level, productivity and technique content are low while its energy and material consumption is high. Civil Engineering New Technology Research Institute of Xi'an University of Architecture and Technology, meeting the nation's call for wall reform, industrialization and continuable progress, invented a new structural system-Multi-Ribbed Slab Structure (MRSS). The new structure is characterized by low self-weight and high strength, high efficiency in saving energy, construction convenience and low cost. Previous study showed MRSS is superior to masonry structure in economy, technology and aseismic performance. Therefore, to replace the latter with the former has far-reaching importance. The paper probed the possibility of applying MRSS to the upper structure of buildings with commodious space at the bottom, the feasibility of replacing LFSWSUMS with Frame-Supported Multi-Ribbed Composite Slab Structure (FSMRCSS). The paper mainly focused on study on the major bearing member in FSMRCSS-Frame-Supported Multi-Ribbed Composite Wall Beam (FSMRCWB).First of all, the paper carried out test study on four two-spanned model members of FSMRCWB, including three 1/2-scaled two-storeyed models and one 1/3-scaledthree-storeyed model. The study considered such factors as span ratio-l1/l2, height-span ratio-hb/l of the beam, and cavity etc.. The paper analyzed the test results, including analysis on mechanical property of the composite wall beam under vertical loads, and failure mode, deformation capacity, aseismic performance under horizontal loads and constant vertical loads. The paper also compared FSMRCWB with Frame-Supported Masonry Wall Beam (FSMWB). Secondly, by means of Finite Element Method (FEM), the paper studied stress distribution in FSMRCWB under vertical loads and under elastic earthquake force with constant vertical loads respectively. Lastly, the paper, based on mechanical analysis, proposed anti-shear force formula of the composite wall and internal forces formulas of the beam under vertical loads, and aseismic formula of the composite wall and aseimic computation method of the beam.All in all, the paper drew the conclusion that FSMRCWB is superior to FSMWB on aseismic performance, and put forward some advice for the design of FSMRCSS.