Influence Of Construction Waste On Basic Properties Of Foam Concrete

With the development of industry,the energy consumption caused by it is also increasing.At present,building energy consumption occupies a very heavy proportion in China's energy consumption,and it is urgent to reduce building energy consumption.In recent years,more attention has been paid to foamed concrete wall materials due to their excellent thermal insulation and low cost characteristics.Because the mechanical properties of foamed concrete are not very high in the use of wall materials,the research on the use of foamed concrete to eliminate construction waste and mineral waste residue is gradually carried out.This subject mainly studies the effect on the main properties of foamed concrete when the abandoned building mortar and the abandoned red bricks are mixed in foamed concrete.After the construction waste pretreated by jaw crushing and powder grinding,study on Granular Allocation and Activity Index of Construction Waste,the fine sand is replaced by the way of particle size of 80 plus m and the cement is replaced by particle size of 80 plus m.The effects of 10%,20%,30%and 40%construction waste of different substitutions on the density,3d,7d,28dcompressive strength,softening coefficient and affthermal conductivity of foam concrete with design dry density of 1100kg/m~3,1200kg/m~3 and 1300 kg/m~3were studied respectively.The study found that adding construction waste can reduce the compressive strength of foma concrete 20%-65%,reduce the softening coefficient by 6%,and improve the thermal insulation ability,and have little effect on the density of foam concrete.Through XRD and SEM analysis,the 28d foma concrete of construction waste was found that the addition of waste red bricks powder can significantly increase the silica content in foam concrete,while and this shows that there are more pozzolanic reaction and carbonation reaction progress take place by this time,the waste mortar can also increase the silica content but not obviously.The morphology of abandoned red brick powder particles is better than that of building mortar particles.The addition of construction waste will increase the number and pore size of foam concrete micropores.