Study On Lightweight RC Multi-rib Sandwich Slab Structures

Light weighted reinforced concrete multi-rib sandwich slab structure system is a kind of new system, which can entirely replace the brick composite system to be adapted to the policy of wall materials reform of our country. It includes two types: the framework system and the non-framework system. The former consists of sandwich panel and frame structure, becoming light weighted frame slab structure. In this system the frame and the sandwich panel together resist horizontal and vertical loads. The main components of the latter are multi-rib sandwich panels, including floor slabs and wall slabs. Reinforced concrete conformation columns are set where the longitudinal walls and latitudinal walls intersect and copulative beams are set where floor slabs and wall slabs intersect. They play a role of linking and transferring loads, bearing a small part of loads at the same time. This thesis only has a discussion on the non-framework system and the following work is done:1.The structure constitution and the formation traits of the main components of the system are discussed. The emphasis is placed on the connection features between the main components, in accordance with the basic principles and requirements, which demand that the integrality of the structure and the safety for loads transfer be ensured.2.A predigestion analysis method for the structure system is brought forward, which is based on the rule that the whole stiffness of the equivalent concrete walls should be equal to that of the former wall slabs, so that the original system can be treated as a reinforced concrete shear wall system. Calculation methods of concerning elastic constants are set forth, supplying a certain theory gist for the structure design.3.Production craftwork of main prefabrications and construction technics of the whole system are described in this thesis and the stress is put on the construction methods of the in-situ sandwich floor boards and the design of its supporting system, combined with current relative construction criterion and the special traits of the system, providing construction reference for the system.4.Based on the economical and technical analysis theories and methods forarchitecture, combined with an engineering example, the thesis compares the system with composite system. The analysis shows that the structure cost of the system decreases 5%-10%,structure engineering man-hour 20%-30%,employable areas increase 3%-5% and the energy cost can be reduced greatly. A lot of performance of the system takes precedence over the concrete brick system and the light weighted frame system.