Study On Volcanic Slag Concrete Composite Self-insulation Block

Nowadays,the whole society is facing the problem of energy shortage,building energy efficiency is an urgent matter.Therefore,China vigorously supports the development of new wall materials to improve the thermal insulation conditions of building exterior walls and achieve the goal of building energy efficiency.This paper presents the green energy-saving wall material-volcanic slag concrete composite self-insulation block,which is combined with volcanic slag and foam concrete to achieve the better results.At present,our country is implementing the strategy of "the belt and road".All countries along the route need to build a lot of infrastructure,which will consume a lot of building materials.Volcanic slag is a kind of light and porous material formed during volcanic eruption.There are abundant reserves in China and other countries along the route.It can be used to prepare concrete,which can effectively reduce the consumption of traditional building materials.Foam concrete is supported by national policies and widely applied in practical projects with the characteristics of light weight and thermal insulation.The research shows that the composite self-insulation block proposed in this paper meets the current energy efficiency standards and the strength requirements of wall blocks.The main work of this paper is as follows:(1)Foam concrete:By changing the admixture content to adjust the pore structure of foam concrete.The variation trends of pore structure and compressive strength of foamed concrete are summarized,which provide a theoretical basis for optimizing the pore structure and improving the compressive strength of foam concrete.By testing the thermal conductivity of several groups of ultra light foam concrete,the relation curve between apparent density and thermal conductivity of foam concrete is drawn,and the prediction formula of thermal conductivity of super lightweight foam concrete is put forward.(2)Volcanic Slag Concrete:Four kinds of granular slag aggregates are selected to prepare concrete,the compressive strength and apparent density are taken as control targets,one-component and multi-components(including two-components and three-components)slag aggregates are used to prepare dry-hard concrete.By testing the compressive strength and apparent density of dry-hard slag concrete with different aggregate gradations to study on the influence of aggregate gradation on the performance of dry-hard slag concrete.The relationship between compressive strength and apparent density of dry-hard slag concrete and the suitable mix ratio of dry-hard slag concrete for self-insulation block production are put forward.(3)The following conclusion is drawn by analyzing the compressive test process and failure mode of the self-insulation block:matrix strength,verticality,combination mode,void ratio and width are the main factors affecting the strength of block.The density grade includes 700kg/m3,800kg/m3 and 900kg/m3.The average compressive strength meets MU3.5 grade.(4)Masonry:Theoretical value of masonry heat transfer coefficient is calculated according to GB50176-2016 "Code for thermal design of civil buildings".The result shows that the thermal insulation performance of the self-insulation block masonry using inorganic thermal insulation mortar is well,it can meet energy-saving requirements for exterior wall enclosure structures in beijing area.In this paper,the components of volcanic slag concrete composite self-insulation block are systematically studied,which provides a reference for the study of self-insulation block in the future.Through the study of thermal performance of self-insulation block,it is considered that the composite self-insulation block is worthy of popularization and application.