What are the features and uses of recycled aggregate
published date: 09-23-2020
What is recycled aggregate
Recycled aggregate refers to the reuse of waste concrete, construction slag, etc., mainly to save resources and reduce pollution. The low density of recycled aggregate is beneficial to earthquake resistance and reduces the weight of the structure. As the density of recycled aggregate decreases with the decrease in the strength of the parent concrete, the reduction rate reaches about 7%. When the crushing index of recycled aggregate becomes larger and the strength of the aggregate decreases, the apparent density and bulk density of the aggregate also decrease. It becomes smaller.
Features of recycled aggregate
The water absorption rate of recycled aggregate is greater than that of natural aggregate. When the particle size of the aggregate is 5-20mm, the water absorption rate of natural aggregate is about 2.2%, and the water absorption rate of recycled aggregate is basically 4%-10%. between. The main factors are: the main reason why the water absorption rate of recycled aggregate is greater than that of natural aggregate is that the surface of recycled aggregate is wrapped with a layer of mortar. This layer of mortar makes the surface of recycled aggregate rougher and more angular than natural aggregate surface; and parent concrete The damage accumulated in the process of disintegration and crushing of the block causes a large number of micro-cracks in the mortar on the surface of the recycled aggregate. These factors greatly increase the water absorption and water absorption rate of the recycled aggregate. The water absorption of recycled aggregate increases with the decrease of aggregate particle size. The water absorption rate of recycled aggregate is also affected by factors such as the strength and composition of the parent concrete material and the climatic conditions of the use environment. The water absorption rate of recycled aggregate is closely related to the crushing index.
The water absorption rate increases with the increase of the crushing index. The main reason can be explained as the increase of the crushing index of the recycled aggregate and the cement mortar on the surface of the aggregate The more covered, the greater the void ratio of the aggregate surface, and therefore the greater the water absorption rate of the aggregate. At the same time, the drier the environment of the parent concrete, the longer the use time, and the greater the water absorption rate of the recycled aggregate. The compressive strength of recycled aggregate concrete decreases as the replacement rate of recycled aggregate increases, and decreases as the water-cement ratio increases. The tensile strength of recycled aggregate concrete is less affected by the substitution rate. As the replacement rate of recycled aggregate increases, the slump of recycled aggregate concrete decreases sharply, the elastic modulus decreases, the shrinkage value increases significantly, the frost resistance basically remains unchanged, the permeability increases, and the carbonization rate slightly increases , Slightly reduced sulfate resistance.
Recycled aggregate equipment
LZZG is a manufacturer of recycled aggregate equipment. The main products are crushers, sand making machines, sand washing machines, spiral classifiers, and sewage purification equipment.