The Study Of The New Composite Insulation Block And Its Masonry Strength

At present, China’s cold, cold area of more than 90% of the buildings using block and thermal insulation material separation technology. There are serious of the durability problems and fire safety hidden troubles in the technology process. The external wall thermal insulation engineering discipline in our country stipulated in the service life of exterior wall thermal insulation system should not be less than 25 years, but the general principles of the civil building design rules general building service life for 50 to 100 years. In fact, research shows that external insulation life really can reach 25 years of the project is not much, mostly less than ten years will appear crack, falling down and other bad phenomena, causing secondary repair which caused huge waste. Breaking the tectonic pattern of traditional concrete hollow block, this paper puts forward the new composite heat insulation block, consists of three layers of concrete slab and two layers of composite insulation material, using special tectonic pattern and construction technology, thoroughly eliminate the phenomenon of cold bridge, heat preservation effect is good, and solve the existing problems of exterior wall thermal insulation. This study used 100% recycled aggregates at the same time, energy saving, environmental protection, recycling.Specific work methods and research results of this study are as follows:1) Determine the proportion of concrete materials used for the block. NC concrete using natural gravel as the benchmark, at the same time design RC-0, RC-3, RC-5 three groups of recycled concrete with diatomite content mixture ratio 0%,3% and 5% to research the effect by different dosage of calcined diatomite, on the improvement of the recycled concrete compressive strength. It is concluded that the dosage of 3% has the best performance, determining the RC-3 groups for the final mix proportioning.2) Research the basic mechanics performance of the new composite block. According to GB/T 4111-2013 "test method for concrete block and brick block", research the compressive strength, flexural strength, volume density, moisture content, water absorption, dry shrinkage, softening coefficient, frost resistance and other such performance, all consistent with index requirements of JG/T 407-2013 "the insulation concrete composite block".3) Research new composite thermal-insulating blocks of thermodynamic performance. Using the theory of thermal calculation and ANS YS finite element analysis these two kinds of methods to analyze block thermal performance. It is concluded that the heat transfer coefficient were 0.38 W/(m2 · k) and 0.46 W/(m2 · k), conforming to the cold region, cold region rural residential building palisade structure of wall thermal insulation requirements.4) Study the basic mechanics performance of the new composite self-insulation block masonry. Design M1, M2, M3, J3 four groups of masonry specimens to research the axial compression of masonry performance influence factors, the constitutive relation, failure pattern, and other such performances, it is concluded that the destruction process and constitutive relation of the block without reinforced masonry is different from the traditional masonry, its concluded is buckling failure pattern. Reinforced masonry and traditional masonry are similar. Design N1, N2 and N3 three groups of masonry specimen to research the influence of different block masonry mortar strength on the joint shear strength, and do theoretical analysis. Experimental results show that the shear strength experimental value is smaller than the calculated value, mainly caused by the release agent and load factor.In this paper, the new composite insulation block has a good thermal insulation performance, suitable for use in cold region, cold region promotion. The block basic mechanical properties are conform to the requirements of the relevant specification, but carbonization performance needs further research. Recommend using mortar a level higher above block masonry in building process, and needing to join the steel mesh as a main wall to improve masonry integrity, stability. Remains to be determined the joint structure and the construction practice suitable for the block masonry by further research. Also need preparing the wall masonry standard drawing to promote the usage of the new composite insulation block.