Thermal Perfomance Analysis Of Interlocking Self-thermal Insulating Concrete Biock Masonry Walls

The heat loss of the enclosure structure accounts for about70%～80%of thewhole building heat loss. It is imperative to improve the thermal insulationperformance of the enclosure structure. The exterior thermal insulation system ofexternal wall has three major disadvantages: complexity in construction, poor fireresistance and bad durability. It is found that the self-thermal insulation system forexternal wall can overcome these shortcomings, and it is worth to be used widely inactual engineering. The thermal performance of this self-insulation block masonrywall was investigated in this thesis.In this thesis, a kind of interlocking hollow concrete block was designed. Theshell is made of light weight aggregate concrete, where a kind of clay ceramisite isused as the light weight aggregate, the bulk density of which is660kg/m3. Thehollow block has three holes inside and the infilling material of the block ispolystyrene board with heat conductivity0.038W/(m·K). Its outward appearanceseems like ‘T’ shape. Due to its T-shape, the cold-bridges are eliminated to themaximum extent. By means of thermal resistance analysis, the detail structure of theblock with size of390mm×250mm×190mm has been defined with70mm as thewidth of the filling holes,25mm as the width of the shell ribs and12mm as thewidth of intermediate air layer.For the purpose of promoting the application of self-thermal insulation systemfor external wall, this paper analyzed the thermal performance of the block masonrywall by employing the ANSYS software. By means of the numerical simulation, thetemperature and heat flux distributions were obtained, and the heat transfercoefficient was calculated with these data. The effectiveness of the numericalsimulation was manifested by the result of the experiments. Then, by using the samemodel the masonry walls in different situation according to various infillingmaterials were studied. The results showed that heat conductivity reductions ofinfilling materials resulted in the decrement of the heat transfer coefficient ofmasonry wall, and the decrease magnitude was gradually increased. As to themasonry walls with standard size block, they all met the requirements of buildingenergy standard when the heat conductivity of infilling materials were not more than0.05W/(m·K).Subsequently, in order to broad the selection range of infilling materials, thepaper was focused on simulating block masonry walls with different block detailsizes and different infilling materials. The temperature distribution and heat transfercoefficient of the masonry walls were gained from the numerical experiments. The main results of these studies were the matching relationships between the infillingmaterials and width of the filling holes, which two combinations could meet thecurrent building energy-saving standard.