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Expressway projects, paved roads, erected monuments, connected to the heart, and accessible to the rich.

In 1932, the world's first highway (the Cologne-Bonn line in Germany) was opened. In 1990, the first standard expressway in mainland China (Shenzhen-Dalian Expressway) was opened. According to statistics, the total length of expressways in my country has now exceeded 140,000 kilometers, ranking first in the world. In the process of urbanization in the world today, the construction of highway projects has stimulated urban economic growth and produced huge social and economic benefits.

China's highway total mileage ranks first in the world

Generally speaking, limestone and granite are the best stone materials required for highway pavement engineering, and basalt and diabase are required to be darker in color for asphalt pavement. The maximum particle size of the crushed stone is 31.5mm, and it is advisable to prepare materials according to the four specifications of particle size 9.5 mm～31.5mm, 4.75 mm～9.5mm, 2.36 mm～4.75mm and 0～2.36mm. The crushing value of crushed stone should not be more than 28%, and the content of coarse aggregate needle flake should not be more than 18% (preferably not more than 15%). Particles smaller than 0.6mm in the crushed stone must be tested for liquid limit and plasticity index. The liquid limit is required to be less than 28% and the plasticity index is less than 9. In order to reduce cracks in the base layer, three restrictions should be achieved: limit the amount of cement on the basis of meeting the design strength; limit the amount of fines and powder while reducing the mud content; limit the water content according to the climatic conditions during construction. During construction, the cement dosage should not be more than 5.5%, the content of particles smaller than 0.075 mm in the synthetic gradation of crushed stone should not be more than 4%, and the water content should not exceed 1% of the optimal water content.

Expressways are like capillaries, giving the country a new orientation for urban transportation. In order to fully guarantee the construction quality of national highway projects, many domestic mining machinery manufacturers have introduced new types of jaw crushers, cone crushers, impact crushers, vertical shaft plastic sand making machines, and high-fine crushers through continuous technological innovation. Advanced equipment such as sand making machine and mobile crushing station.

Recently, in the construction of the Chongqing Kaizhou-Yunyang expressway project, the mobile tyre crushing station from Sanming Heavy Industry under Chongqing Longjian Machinery has been favored again. The crushed stone is of high quality and meets the high standards of high-speed road construction stones.

Sanming Heavy Industry, a subsidiary of Longjian Group, has nearly 30 years of rich experience in the production of complete sets of stone and sand production equipment. Friends from all walks of life are welcome to visit and guide. National 24-hour hotline: 19123267765.