Study On Test Method And Evaluation Index Of Ceramsite Foam Concrete

As a new type of building insulation material,the ceramic foam concrete has not yet promulgated relevant industry and product standards.The domestic market of ceramic foam concrete has already formed a huge industry.It is urgent to formulate relevant standards to standardize its performance requirements and test methods,improve the overall quality of ceramsite foam concrete products,regulate market order,and promote the application of this product.Provide technical support for healthy development.In this paper,a key index reflecting the performance of ceramsite foam concrete is proposed.The key parameters are classified into physical mechanical properties,durability performance,thermal conductivity and radiation performance.The selection of test methods for different performance related items was carried out.The test methods that were more consistent with the characteristics of ceramsite foam concrete were studied.The items included dry apparent density,thermal conductivity,compressive strength,volumetric water absorption,softening coefficient,frost resistance,drying shrinkage value,radiating and homogenization.In this paper,the test method of dry density is first discussed.It is found that the highest drying temperature selected when measuring dry density of ceramsite foam concrete will affect the final test results.The maximum drying temperature is controlled at the drying temperature between 60 and 80 degrees.Secondly,the pretreatment method of compressive strength test block is discussed,and the temperature rise rate and the maximum temperature confrontation are analyzed.The influence rule of compressive strength is then compared with the difference between volumetric water absorption and mass water absorption.It is determined that lightweight foam materials are more suitable for volumetric water absorption to reflect their true water absorption rate.Subsequently,it is found that although the radioactivity of light ceramsite grinded is higher than that of untreated ones,it has no substantial effect on the radioactivity results,while the radioactivity of samples gradually increases with the increase of water content.Finally,it is suggested that the frost resistance index of the ceramsite foam concrete in the north area should be tested.The test method of frost resistance needs to be formulated according to different parts and environment,so that the test can simulate the actual freezing and thawing process more truly.By analyzing the situation of ceramsite foam concrete with different density levels produced by dozens of enterprises across the country,the distribution of statistical data was made,and different evaluation indexes were formulated.It is concluded that the density range of ceramsite foam concrete is directly proportional to its thermal conductivity and compressive strength.It is suggested that the grading of ceramsite foam concrete should be evaluated in terms of uniformity,dry apparent density,thermal conductivity,compressive strength,volumetric water absorption,softening coefficient,frost resistance and drying shrinkage value.