浅谈我国多层混凝土框架结构设计(5)

structure can have good ductility and seismic performance. However, the frame structure to withstand the level of forces (wind loads and horizontal seismic action) capacity less. When the layer of the tree more or larger horizontal force, horizontal displacement of large, often under strong earthquake in as deformation caused by excessive non- structural elements (such as filling wall) damage. Therefore, in order to meet the requirements of the bearing capacity and lateral stiffness, the column sections are higher, both cost building materials, but also reduce the use of space. This makes the framework structure of the building height subject to certain restrictions. At present, frame structure generally used for multi-storey building and not considered earthquake-proof, low-rise high-rise buildings (for example, layers for the 10-story height of 30 meters or less)

2.3 Frame structure of the layout

Multi-storey frame structure of the plane layout is flexible, frame structure in accordance with the loading of the different ways into the following three categories:

(1) Horizontal load-bearing framework of the program to the framework of the main beams as floor beams, floor load borne mainly by the horizontal framework. As the number of horizontal frame less often, the main beam along the crosswise arrangement is conducive to enhance the lateral rigidity of housing. Meanwhile, the main beam along the crosswise arrangement is also beneficial to building ventilation and lighting. However, the main beam section size larger, as the housing needs of a large space, low headroom, and not conducive to vertical pipe layout.

(2) The vertical load-bearing framework of the program to the main frame rails as floor beams, floor load borne by the frame rails. As the beam cross-section small size is conducive to walking through the pipeline facilities, access to higher indoor clearance. However, poor housing lateral rigidity, while the depth scale by the limited length of precast panels.

(3) vertical and horizontal program to the framework of the mixed-load bearing vertical and horizontal program to the framework of the mixed two directions along the vertical and horizontal layout of a framework for both the main beam as the floor beams, floor load from the vertical and horizontal frame beams shared. It is well overall performance.

2.4 The way board section design and construction and reinforcement

Beam around the entire cast for the two-way board, because in both directions by the support component of deformation constraints, block board the role of memory in the dome, so that the moment plate greatly reduced. Referred to in order to take advantage of this favorable factor, standard allows the entire end plate edges and the beam, from the moment the design value reduction under certain conditions. Thickness of not less than two-way plate 80mm. As the deflection is not a separate checking, two-way plate thickness and the ratio of short-span is long