Study On Mechanical And Thermal Properties Of Modified Raw Soil Brick Multifactorial Relevance

The raw soil material in northwestern areas is a kind of natural material that is widely distributed and largely reserved,raw earth buildings have the advantages of low resource consumption,high energy efficiency,simple construction and friendly environment,it can be made into a kind of construction wall material that is cheap,ecological,energy-saving and suitable for living.However,the raw soil material is lack of durability and mechanical property,which are the bottleneck of its application.Therefore,to pass on this valuable type of building,only fundamentally improve its mechanical and thermal properties.In the modified soil research done in this paper,a small amount of glutinous rice pulp is added as an ancient building material and building cement.From this point of view,the effects of external multi-factor effects of density,age and added materials on the mechanical and thermal properties of modified green bricks were studied.In this paper,the raw soil materials are modified to meet the basic strength requirements of the raw soil buildings.On this basis,the raw soil materials with ideal thermal properties are sought.In the thesis,under the premise of considering material active influence factors in advance,testing programmer is arranged by considering density as the single influence factor.And a physical equation hidden in the material is drawn through a series of experimental results and a regression equation: the correlation between the raw soil material and its influence factors.So that the material properties can be predicted through changes of influence factors or changes of influence factors be controlled through the material property demands,in order to be close to the property optimum point.The final goal is to change influence factors conditions and upgrade the material properties.In summary,the raw soil material is the researched subject in the thesis,correlation between properties and influence factors as well as corresponding influence factors conditions are drawn,the effects of mechanical and thermal properties of modified green brick materials under multi-factors were studied.The preparation parameters and production process of modified green brick materials were preliminarily studied.There are many factors that can influence the mechanical properties,thermal properties and durability properties of the modified raw soil brick: density,mix proportion,optimal moisture content and choices of different modified materials.The raw soil brick with six different densities and same mix proportion and other factors is deemed as the researched subject,the interaction influence rule between compressive strength and heat-conducting property of the modified raw soil brick with different densities is researched and prediction model is inferred on the basis of this.The main results show: 1.compressive strength and heat-conducting coefficient are in direct proportion to that of dry density;2.The relevance between compressive strength and heat-conducting coefficient with different densities is a physical equation characterized by something that is similar to a quadratic parabola;3.For the physical equation between compressive strength and heat-conducting coefficient with different densities and the same mix proportion in the thesis,the heat-conducting coefficient is in direct proportion to that of the strength when the compressive strength is below 8.50 Mpa,while they are in inverse proportion when the compressive strength is above 8.50 Mpa.4.In the experiment,we also noticed the mutual interference problem caused by the external factors of one of the added materials.The conclusion can provide reference for further research on modified soil materials.