Research And Application On High Strength And Performance Fly Ash Lightweight Aggregate

Based on theoretical principle and technological methods of material science,a kind of technological method of manufacturing high strength and performance sintered lightweight aggregate with fly ash as main material is put forward through exploring key technology and various optimized process parameters.At present domestic produced lightweight aggregate of lower strength and higher absorption of water is common. How to better property of lightweight aggregate is always a concerned question. Now people have advanced various technological methods to solve those questions,but the effects are not obvious still. Different from average lightweight aggregate,high strength and performance lightweight aggregate possesses characteristics with higher strength,lower absorption of water and super fractions and is applicable for production of outstanding concrete with better workability,physical mechanical property and durability. Experiment adopts a series of technology,such as expansion technology,solid burning technology,mullite crystallizing technology and anti-clarifying technology etc. Through orthogonal optimized proportion and suitable accelerated burning test,experiment has successfully produced high strength and performance fly ash lightweight aggregate. Its pile density is 850Kg/m3 or so,belonging to 900 grade,tube strength is over 8.0MPa,20% higher than that of state standard and absorption of water is below 5.0%.Burning experiment of various materials proves that burning mode of high strength and performance lightweight aggregate is different from that of common light aggregate. Burning mode of high strength and performance lightweight aggregate is a combination of suitable expansion and contraction,and emitting gas and saving gas.Using the sintered fly ash lightweight aggregate,the experiment has successfully compounded lightweight aggregate concrete with properties of compressive strength more than CL60,0 minute slump more than 20cm,expansibility more than 50cm and 60 minute slump no less than 18cm. The result indicates that this lightweight aggregate concrete can be applied widely.