What are the common problems of asphalt in pavement application? Next, Jinan asphalt concrete manufacturer will introduce the possible causes of asphalt macadam segregation zone for reference.
1. Possible causes of segregation zone formed by asphalt macadam
(1) When the asphalt mixture is transported from the storage tank to the transport vehicle, due to the height, the large aggregate rolls down near the carriage, forming a single concentration of coarse aggregate.
(2) When the mixture in the transport vehicle is discharged to the paver, the large aggregate rolls down near the half car of the paver, forming the secondary concentration of coarse aggregate.
(3) During the feeding process of the paver feeder, the intermediate aggregate is first sent to the distributor, and the remaining coarse aggregate is stored in the hopper. When the paver collects the hopper, the third concentration of coarse aggregate is formed.
2. Hazards of asphalt macadam segregation
(1) Once the coarse aggregate of asphalt macadam is concentrated, the aggregate is very easy to be crushed during the rolling process, and the aggregate surface area increases, which changes the original design pavement mix ratio. The oil is too small, causing the aggregate to become loose after rolling, damaging the pavement structure, affecting the pavement strength, driving safety, driving effect and road service life.
(2) Coarse aggregate is concentrated, the local compactness is poor, and the porosity is high. It is easy to form ponding on the pavement, which affects the pavement quality.
(3) The coarse aggregate is concentrated, which affects the pavement evenness and aesthetic appearance.
3. Methods to solve the segregation zone formed by asphalt macadam
(1) Solve the problem in terms of transport vehicles
When discharging materials from the mixer storage tank to the truck, the materials shall be discharged in three layers, that is, the truck shall move one position for each bucket of mixture. After the first layer is finished, the second and third layers shall be placed one by one to reduce the concentration of coarse aggregate.
During the construction, there is a truck waiting for unloading in front of the paver, that is, the traffic volume of the truck for paving asphalt mixture is richer than the auxiliary paving speed.
(2) Solve the problem from the operation of paver itself
Install reverse spiral blades at the side end of the one half of the auger of the paver; Control the auger in the middle or high gear position; Control the appropriate opening of feeding silo; Operate the feeder and auger evenly; When the paver has finished paving a truck of materials, control the speed of the paver, turn off the feeder, and feed and distribute materials evenly after the materials are poured in; Keep the spreader of the paver rotating constantly during the paving process, and keep the mixture at least two-thirds of the height of the feeder on both sides of the paver.
(3) Solve the problem from the mixture itself
Reduce the suspension of mixture particle size. Control the asphalt dosage to make it higher than the design dosage.
The possible reasons for the formation of segregation zone of asphalt macadam and the related solutions are explained here. Please come to our website for your ideas http://www.ycgjglcl.com Share.