Research On Heat Transfer Performance Of Straw Concrete Wall

People's needs for diet are diverse.Wheat,corn,rice and other crops are essential for people's livelihood,which means that straw is a must-have product every year.So far,there are no effective measures for the post-treatment of straw.If the products of burning straw are discharged into the air without treatment,it will have an extremely bad impact on the environment.As the annual output of straw increases year by year,burning straw used for heating can not solve the real problem.If the straw is incorporated into the concrete as a wall material,a part of the straw can be disposed of without pollution.Due to the material properties of the straw,adding it to the concrete can improve the insulation performance of the concrete wall on a certain extent.Therefore,researching on this new type of concrete wall material is crucial for today's society.Paper will focus on the following aspects of experimental analysis:1.Determination of mechanical properties of a new straw concrete wall.This part mainly uses the method of experimentation.The straw concrete materials with different straw contents are sampled separately to form concrete test blocks of standard specifications.The pressure values that they can withstand are measured separately.The test blocks are selected that meet the national wall strength requirements,and we record the corresponding compressive strength value and straw incorporation.Through the test,whether to add fly ash,the mass percentage of the straw is1% and 2%,and the compressive strength of concrete test blocks is higher than30 MPa.It meets the standard of mechanical conditions for C30 concrete and can be put into use as a wall material.When the mass percentage of the straw is 3%,the compressive strength of the concrete test piece only incorporated into the straw reaches 25 MPa.When the mass percentage of the straw is 4%,whether the fly ash is added or not,the compressive strength of the concrete test block is higher than 20 MPa.When the mass percentage of the straw is 5%,whether the fly ash is added or not,the compressive strength of the concrete test piece is less than 20 MPa.2.Analysis of heat transfer performance of a new straw concrete wall.Thispart uses a combination of experiment and software simulation methods.The thermal conductivity of straw concrete was measured by using a JTRG-III thermal conductivity tester,and we write down the corresponding data.Combined with the finite element analysis software ANSYS Workbench,the temperature field inside the straw concrete wall is simulated.The temperature distribution curve of the new straw concrete wall under steady state and nonsteady state is obtained.We analyze the heat transfer performance of the new straw concrete wall.The data from the experiment shows that,in steady state and transient conditions,when only straw is added to the concrete with the mass percentage of1%,2%,wall insulation performance is increased by more than 70%.In the case of mixing fly ash,when the mass percentage of straw added to concrete is 1% or2%,the insulation performance of the wall is increased by at least 90%.