Preparation And Compressive Properties Of Double Density Light Wall Materials

More and more lightwight and energy-saving materials continue to emerge with the reform of wall materials innovation, and widely used in urban construction. This paper developed a new lightweight block which meeting the wall reform policies to solve the problems existed in current commonly used materials.Dual-density lightweight block studied in this paper mainly used normal density of ordinary concrete materials for the border and internal rib pillar, which playing a main role of load-bearing, and the hollow part filled with low-density foam concrete materials, which playing a main role of acoustic insulation, thermal insulation and light weight. It is a new wall material, which has many advantages, such as low cost, land conservation, energy saving, use of waste, light-weight, heat-preserving, sound absorbing and so on. It can solve the problems existed in the traditional block such as hot, cracking, seepage, poor thermal performance. It is consistent with the policy of sustainable development, and represents the development direction of masonry structural materials. Its play a huge role in improving the quality of construction, architectural features and improving people’s living and working environment, which has broad application prospects.On choosing appropriate element type, constitutive relation, failure criterion and so on, the finite element model of the dual-density lightweight block is built. Four models of dual-density lightweight block in different structurals are calculated to simulate stress distribution characteristics, compressive strength, displacement deformation and development of cracks, which could understand the basic physical properties of this kind of blocks and increased the intensity of promote the use, and obtain the weak areas of the force in theory. Meanwhile, the method of measuring the pore structrue of foam concrete based on image analysis was studied in this paper. The water cement ration(W/C), content of foaming agent (H2O2), content of fly ash (FA) and content of polypropylene fiber (PP) on on density,28d compressive strength, acoustic absorbing coefficient and pore structure of foam concrete was also studied. The main results obtained are listed as follows:(1) With the W/C and content of H2O2increasing, the porosity and average pore size of foam concrete increased, the density and28d compressive strength decreased, the acoustic absorbing coefficient increased first but then decreased, its highest when the W/C is0.7and the content of H2O2is6.5%.(2) With the FA and PP content increasing, the porosity and acoustic absorbing coefficient increased, the density decreased, the28d compressive strength increased first but then decreased with the FA content increasing and highest at30%, while the strength almost constant with the PP content increasing.(3) The failure form of four different structural blocks in vertical ultimate bearing capacity was researched under simulated limit analysis. According to the results of the test, normal density of ordinary concrete materials for the border and internal rib pillar and the hollow part filled with low-density foam concrete materials work together under the vertical loading; ordinary concrete materials playing a main role of load-bearing, while low-density foam concrete materials playing a main role of load-transfer; it has good ability of deformation due to the restraint of rib to inner low-density foam concrete; the deficiency of transverse tensile stress is the fundamental reason of its destruction.(4) The comparing compression test in four types block was studied. The cracking load, ultimate failure load and vertical deformation characteristics with different structure blocks were analyzed according to the experimental results and data. By comparison with the simulation results to verify the feasibility of the established model, which providing an effective adjunct for further study of the mechanical properties of block.(5) Finally, the complete study was summarized and reasonable proposal based on the results was presented, at the same time, the views in the further study on the subject of the question were put forward.