Service Hotline
+86-21-33781259
Introduction to gravel aggregates for expressways:
In the construction of expressway, high requirements are placed on the aggregate shape and gradation of concrete aggregates, especially the pin-like content in basalt (diabase) gravel. In order to solve the requirements of particle size and gradation, particle shape, consistency of particle composition, cleanliness and particle content of 0.075mm, Phoenix has added a new sand making machine to better meet the highway cement in the production line configuration. , asphalt and other requirements for sand and gravel aggregates.
High-speed road aggregate production process:
The mined stone is firstly fed by the vibrating feeder to the jaw crusher for preliminary crushing. The secondary crushing is completed by the cone breaking. The material broken by the cone is sieved on the vibrating screen. The material larger than 40mm is returned to the cone and broken again to form. Closed loop, less than 40mm material enters the vertical impact to break and shape. The finished product sieved by the vertical impact material is sieved, and the returning vertical impact breaking cycle of more than 20 mm is broken, and the materials less than 20 mm are conveyed to the respective finished material piles by the belt conveyor.
Sand and aggregate production line performance:
The stone production line has high degree of automation; its production efficiency is high, the operation cost is low, the output is large, the income is high; the discharge particle size is adjustable, the breaking rate is high, and the energy is saved; the finished stone has uniform particle size and good granular shape, and meets the national high-speed material standard.
Sand and gravel aggregate standard for highway construction:
The gravel aggregate used in highway construction has a high standard in quality, which puts higher requirements on the crusher equipment! At present, there are many problems in the production of gravel in China. For example, the crushed gravel is generally coarser in particle size, and the mixture is seriously segregated; the needle-like content in the crushed stone exceeds the standard; the supply instability affects the grading of the mixture frequently, etc., which have a good effect on pavement construction and pavement quality. Great impact! In order to ensure the quality of expressways, relevant departments have strict standards for sand and gravel aggregates for highway construction. The following is a brief introduction for the customers who are ready to engage in the supply of gravel aggregate for highway construction:
First, the shape of the particles
Second, the size and gradation of the particles
Third, the consistency of particle composition
Fourth, keep the particles clean
Fifth, control the content of 0.075mm particles
The stone crushed by the crusher should be a cube, the needle-like particle content of the coarse aggregate should not exceed 15%, and the ratio of the minimum thickness to the maximum length of the needle-shaped particle system is less than 1:3. The angular particles produce greater mechanical stability than the round particles.
Grading is the most important characteristic of aggregates. It directly affects almost all the important characteristics of the mixture, especially for asphalt concrete. The high precision of the grading ensures that the Marshall stability and flow value of the concrete are in optimal design conditions. Otherwise it will reduce the service life of the road.
It is important to ensure the consistency of the particle composition to maintain the consistency of the gradation composition of the mixture and the consistency of various technical indicators. If the composition of the mixture changes greatly, it will significantly affect the quality and service life of the pavement.
The presence of harmful substances such as clay, vegetation and excessive dust formed by the crushing of the aggregate particles will cause the asphalt mixture to peel off and loosen to affect the durability of the asphalt pavement.
The content of 0.075mm particles in the water-stable base mixture should not exceed 5%-7% to reduce the shrinkage of the cement stabilized pellets and improve their anti-scour ability. The coarse aggregate used in the asphalt surface layer requires the water washing method to be less than 0.075 mm and the particle content is not more than 1%, mainly to control the mud content which is soluble in water.
For more information, please call +86-21-33781259