Experimental Study On Mechanical Concrete Properties Of Porous Brick Masonry With Iron Tailed Stand And Pumice

The use of clay bricks in China is gradually prohibited,and new wall materials are needed for the continuous development of the construction industry.Concrete porous brick emerges as the times require,its energy-saving and environmental protection characteristics make it get continuous development and social attention.In this paper,a new type of environmental protection concrete load-bearing porous brick is firstly prepared by using sealing pumice as coarse aggregate and industrial waste iron tailings as fine aggregate with specific proportion of fly ash and cement.Pumice is a kind of natural resource and natural lightweight aggregate.The lightweight aggregate concrete obtained by using pumice as coarse aggregate has the characteristics of heat preservation and light weight.The pumice resources in Zhangjiakou area are rich,but the utilization rate is not high.If the pumice resources can be fully utilized,it can promote the local economic development and provide a large number of employment opportunities.As an industrial waste,iron tailings can not only solve the problems of tailings pollution and tailing pond occupation,but also effectively protect the excessive consumption of non-renewable resources,which is in line with the need of sustainable development.Based on the theoretical analysis of the porous brick and its masonry of iron tailings pumice concrete,the mechanical properties of the brick and its masonry are tested.Some conclusions and suggestions are obtained through the comprehensive analysis of the experimental data and phenomena.These conclusions and suggestions have certain guiding significance to practical engineering.The study and conclusions are as follows:1)A series of experimental studies on the porous brick of pumice concrete with iron tailings are carried out.The experimental results and the properties of the raw materials of the brick are analyzed and studied.The results show that the compressive strength of the porous brick is MU20,the flexural strength is 4.0 MPa,and the folding pressure ratio is 19.In addition,the results show that the porosity,volume density,water absorption,softening coefficient,dry mass loss and compressive strength of the brick are about 14.5,1900,3,0.89,2.1 and 11,respectively.(2)The compressive,shear and flexural strength tests of the porous brick masonry of pumice concrete with iron tailings have been completed,and its failure characteristics and mechanism have been observed and analyzed.When the test data are compared with the test values calculated according to the relevant formula of masonry structure Design Code,it is found that the strength indexes of the new type of concrete porous brick masonry used in this test are all higher than the calculated values of the code.The axial compression strength is 10%,the shear strength of the joint is 7% higher,the double side damage is 27%,the bending tensile strength is 69%higher and the tooth joint is 58%.Finally,the calculation of each kind of failurestrength is calculated by regression analysis.Formula.At the same time,by analyzing the experimental data of axial compressive strength of concrete porous brick masonry,the elastic modulus and Poisson's ratio of the porous brick masonry are calculated to be 3273 and 0.125 respectively.3)Using finite element software ABAQUS to simulate and analyze the axial compression resistance of brick masonry,the displacement,deformation and stress distribution of masonry under axial compression failure are obtained.The failure mechanism is analyzed according to the results,which is basically consistent with the actual experimental phenomenon.