Performance of Aerated Concrete Blocks Under Varying Temperatures

Aerated concrete blocks (AC) are widely used as masonry in building construction because of their light weight and low density. Try to determine the strength, bonding, cracking and thermal behavior of aerated concrete blocks at different temperatures, mortar ratios and thickness. The results show that at temperatures above 100°C, the strength will decrease and cracks will appear, and the bonding behavior will vary with the thickness and proportion of the mortar. Compared with the solid concrete block model, Thermal Comfort Research shows better thermal comfort.


INTRODUCTION:
Aerated concrete block (AC) is considered a low energy consumption, non-toxic and very sustainable building material with good thermal properties. The main purpose of the experiment plan is to study various technical characteristics of AC blocks, such as compressive strength, density, and thermal behavior.

Materials
The materials used in this study are detailed in the table below:

CEMENT
In this study, the 53-type ordinary Portland cement and its properties according to IS 12269: (1987) are listed in Table 1

FLY ASH
In this experimental study, Class F fly ash collected from near the RMC facility was used. The properties of fly ash are shown in Table 2. target density is not reached, change the water-cement ratio and determine the mixing ratio. Then cast cubes with and without substitutes according to the required density. Record the weight of the mold before and after casting. In this way, the target density that has been reached or not is checked. After the hardening is complete, put the cube into the hardening tank and check the target density of the foam concrete. When the cube reaches the target density, the compressive strength is performed.

EXPERIMENTAL INVESTIGATION
In this experimental investigation, we discuss about performance aerated concrete partial replacement of sand with lime stone powder.

CASTING AND DEMOULDING
Weigh all materials in the electronic measuring equipment. Clean the first mold and apply oil to the inner surface of the block. Then fill the mold with the aligned material at this time without compaction. Then, at this point after 24 hours, remove the square from the shape. Various mixtures are made by changing the mixing ratio. After 24 hours, the mold was taken out of and removed with water.

PROCEDURE
In order to understand the initial trend of temperature fluctuations of aerated concrete blocks, especially , the following research was conducted. Use the saw blade to cut the specimen from the whole block with the size of 600 × 200 × 150 to the size of 150 mm × 150 mm × 200 mm. Six specimens were cut in all, with three specimens being cut from these. Three of these samples were subjected to temperatures of 60°C, 1200°C, and 180°C for 60 minutes in the blocks. Each block was filled with hot air and brought to room temperature before being individually tested for bearing capability. At room temperature, test the load-bearing capability of the other three specimens by immersing them in water immediately after 1 hour of exposure to temperatures of 60°C, 120°C, and 180°C.

COMPRESSIVE STRENGTH
100mmX100mmX100mm cubes are used to prepare 7day, 14-day and 28-day concrete cubes.

CONCLUSION
1. When exposed to 1500°C, the compressive strength of the block decreases sharply, and then the block is immediately immersed in water to cool the block to room temperature. 2. It was discovered that the intensity has decreased by approximately 35%. As a result, it is not suggested to spray water directly on the surface of aerated concrete blocks in the event of a fire. 3. A grouting thickness of 2 mm is not suggested for a 1:6 lean cement mortar mixture. A minimum thickness of 4 mm 4 CM is ideal when utilised as a mortar joint in a 1:6 ratio. At temperatures over 500°C, surface fractures on the plastered surface were detected. 4. However, this will need further test data. According to limited study on the scale model, the Aerated Concrete model provides higher thermal comfort than the Solid Concrete Blocks model.