Brikolite FAQs
All concrete blocks are prone to cracks but they can be minimized by taking certain precautions. Some of the reasons behind such cracking are deflection of beams, uneven placing of blocks, structural movements due to Thermal expansion or change in moisture content. One way to avoid this is to delay the use of the blocks till equilibrium moisture content is reached.
The first course of blocks should be given at least 24 hours to set. Even the framed structure should be given enough time to cure so any change in structure can be noticed. Control joint of 10 mm must be given after every 3 meter from bottom to the top of the wall and the joints must be filled with some resilient material. Expansion joint tiles must be given after every 3rd course and placed between gaps of control joint.
Bond beam must be given after every 1200 mm in height using reinforcement of two MS rods of 8 mm tied with 6-8 mm steel with a gap of 6”-9”. Minimum thickness of bond beam must be taken 3” with concrete cover 15-20 mm on sides. Bond beam must be discontinuous at control joint.
Steel rods must be embedded in column 5-6 times of its diameter and must be fixed using non shrinkable high strength grout. The Mortar Mix for filling the bond beam can be taken as Cement:Sand in the ratio 1:4. The purpose of bond beam is to give stability and strength to the wall.
After every 3rd course, Wall ties must be used between block and concrete column. Due to excessive change in moisture content, all concrete including AAC exhibit change in volume. This is why it is recommended to delay use of AAC for construction by 10-15 days.
The first course of blocks should be given at least 24 hours to set. Even the framed structure should be given enough time to cure so any change in structure can be noticed. Control joint of 10 mm must be given after every 3 meter from bottom to the top of the wall and the joints must be filled with some resilient material. Expansion joint tiles must be given after every 3rd course and placed between gaps of control joint.
Bond beam must be given after every 1200 mm in height using reinforcement of two MS rods of 8 mm tied with 6-8 mm steel with a gap of 6”-9”. Minimum thickness of bond beam must be taken 3” with concrete cover 15-20 mm on sides. Bond beam must be discontinuous at control joint.
Steel rods must be embedded in column 5-6 times of its diameter and must be fixed using non shrinkable high strength grout. The Mortar Mix for filling the bond beam can be taken as Cement:Sand in the ratio 1:4. The purpose of bond beam is to give stability and strength to the wall.
After every 3rd course, Wall ties must be used between block and concrete column. Due to excessive change in moisture content, all concrete including AAC exhibit change in volume. This is why it is recommended to delay use of AAC for construction by 10-15 days.
AAC blocks should be stacked on pallets as they need to be protected from getting damp. Care should be taken for keeping the stacking area or ground clean and level. Blocks should be stacked on their height side and stacked lightly to avoid damage. A systematic stacking also facilitates counting of the blocks.
A low capacity compression testing machine of 250KN and cutting Machine of 2000-3000 KN are not recommended to use. Follow the testing guidelines as mentioned in IS 6441 Part -5. There is difference between immediate density and oven dry density. In normal condition, AAC blocks have certain moisture content so their density is observed to be higher but for testing purpose,we dry the sample at 150 degree centigrade for 4-5 days till constant weight is achieved and then we obtain moisture free density or dry density. After this we can achieve the desired result.
Brikolite AAC blocks recommends, wall can be constructed of minimum 125 mm for internal wall purpose and 150 mm for external wall purpose.
Use any non -shrinkage mortar. First apply thin cement slurry on chase and fix fiber mesh then apply non-shrinkable mortar.
Normal nails once fixed may come out. So it is recommended to use fasteners or screwed nail. Anchors made of plastic and nylon will work. Use power drill for anchoring. For electrical conducting (Jhari), preferably electrical chaser should be used. It gives fine and accurate chasing and no impact on AAC wall. Manual chasing should be avoided.
When we apply mortar on blocks, AAC absorbs certain amount of water from the mortar mix and mix may get cracks. So prior moistening of blocks is essential. For this purpose we sprinkle the block top and side surface with water for few seconds. The purpose is to wet the surface of blocks but not excessive wetting.
Water Absorption Test@24 hour water immersion is not given in Standard of AAC Blocks IS-2185 Part -3.It is recommended to test thermal insulating wall elements like AAC for Capillary water absorption. AAC block is superior for capillary water absorption in comparison to conventional brick. Like red clay brick,AAC is not recommended to use in foundations and damp environment, so water absorption test is not applicable for AAC.
