Study On Temperature Load And Its Effect Of Concrete Block Building

Concrete block, which is a kind of wall material to substitute for clay block. It has a series of technologic economical advantage. But thermal expansion secant coefficient for concrete block is 10×10^-6, it is doubleness of clay block., so concrete block is sensitive than clay block and is easy to bring cracks. Concrete block has been utilized as a kind of wall material for more than 30 years in China. Sufficient experience and fruit has been obtained in application, study and progress about hollow block. With the development of new masonry materials reform and architecture environment conception, masonry structure will progress rapid. But the crack is a bad factor which has restricted concrete block to comprehensive application and development of masonry structure.After consulting many weather datum and calculational methods of temperature stress, the article bring forward a new calculational method of temperature load and summarize distributing rules of temperature and temperature stress of masonry structure under the action of annual temperature change. It offers theoretic basis and applied method for consummating the design theory of masonry structure and resisting temperature change design, achieves calculating temperature stress in building design. At the same time it prevents extending of concrete block and new masonry materials reform, offers theoretic basis for consummating design criterion of masonry structure. The productions include:1. Basing on the weather datum of Qin Huangdao, the article bring forward a new calculational method of temperature load, which is using probability to calculate lunar average maximal or minimal temperature. It considers the concept of recur time and uses extremum typeI distributing to calculate lunar average maximal or minimal temperature load standard value.2. It is assumed that concrete block is homogeneous isotropic material and concrete block wall is infinity, so temperature distributing is along thickness direction. Using large frame analysis software ANSYS analyses concrete block wall under action of difference in temperature on the inside and outside surface. The result is that temperature distributing is along thickness direction and nonlinear, temperature stress distributing is big in the end and small in the middle.3. It is assumed that multiplayer concrete block building predigests two-layer model. The article simulates temperature and temperature stress distributing of concrete block building under action of annual temperature change. The result is that temperature distributing is along thickness direction and nonlinear, temperature stress distributing is symmetry about lengthways axis of the wall, and the temperature stress in the corner of the windows and osculant part between the wall and the beam or the pillar is bigger than the other part.