Experimental Study On Durability Of Self Sisal Fiber Compacting Lightweight Aggregate Concrete

It was found that adding sisal fiber into the self compacting lightweight aggregate concrete can effectively improve the tensile strength of self compacting lightweight aggregate concrete,improve the toughness of concrete and lead to brittle failure.Based on self compacting lightweight aggregate concrete mixed with sisal fiber on the strength grade of C40,studies on the impact of sisal fiber self-compacting lightweight aggregate concrete durability and reveal the mechanism of sisal fiber of self compacting lightweight aggregate concrete by scanning electron microscopy.This paper through a large number of experiments,in the case of ensuring that the strength can meet the requirements of specification and the fluidity is good,the length of 10mm,adding amount of sisal fiber with 2.0kg/m~3and polypropylene fiber with 0.8kg/m~3(the control group as the sisal fiber self compacting lightweight aggregate concrete)respectively are added to the strength grade of C40 self compacting light concrete,experimental study on the durability of.The impermeability test showed that,the sisal fiber self compacting lightweight aggregate concrete,polypropylene fiber reinforced self compacting lightweight aggregate concrete and the blank group of the impermeability grade were P10 and both more than P12.Compared with the control group,it is found that the average seepage height of the self compacting lightweight aggregate concrete increases by37mm with the addition of sisal fiber,and the impermeability of concrete decreases slightly;adding to polypropylene fibers,the average water seepage height of the concrete specimen is reduced by 22 mm compared with the blank group,improve the impermeability of concrete.The carbonization test showed taht,the sisal fiber self compacting lightweight aggregate concrete,polypropylene fiber reinforced self compacting lightweight aggregate concrete and the blank group of the carbonization depth were 4.7mm,4.3mm and 7.2mm.Compacted with the blank group,after adding sisal fiber and polypropylene fiber,the anti carbonization ability of the self compacting lightweight aggregate concrete were improved.The frost resistance test showed that,after 250 freeze-thaw cycles,the maximum mass loss rate for sisal fiber reinforced self compacting lightweight aggregate concrete,polypropylene fiber and the blank group were respectively 1.93%,1.47%and 4.05%,their maximum strength loss rate were 10%,11.3%and 14.3%,they are required to meet the quality loss of not more than 5%and compressive strength loss of not more than 25%of the requirements.After adding sisal fiber and polypropylene fiber,the frost resistance of concrete is improved.It can be seen from the SEM test pictures,after the addition of sisal fiber and polypropylene fiber,the maximum crack width and porosity of self compacting lightweight aggregate concrete was better than the blank group significantly reduced,reducing the number of cracks,improve the compactness of concrete.