A centrifugal process for producing concrete piles in China

[0001] The present invention relates to a manufacturing process of a centrifugal concrete pile. Background technique:

[0002] China since the early 1980s began the introduction, development and production of prestressed concrete pipe pile. 90 years of the last century, pile in the rapid development of our country, from the north coast of Guangdong, at the same time, with the implementation of western development strategy, technology pile all the way west. At present, China's output of concrete pipe pile not only among the world's first column, the type is among the highest in the world. In recent years, prestressed concrete square pile as a new type of pile appeared in the market. Prestressed concrete piles with the same party prestressed concrete pipe pile centrifugal molding process, having the outward appearance of the structure of the circle, easily fixed transportation, banding; when using the probability of pile construction hold pieces holding pressure Pipe accidents than Save small; pile caps dimensions are more reduced, thereby reducing the project cost. Requirements of sustainable development in line with the development of precast concrete piles of building materials, factory prefabricated concrete piles in favor of automation, large-scale, efficient production, not only easy to control and quality assurance, it is also able to reduce the use of non-renewable concrete sand, stone waste of resources, after transport to the construction site, on-site construction is fast, clean construction. Due to the high pile capacity prestressed concrete pipe piles and prestressed concrete square pile (prestressed concrete pipe piles with up to C80 strength grade concrete), more and more sink holes pile, on-site production of reinforced concrete square piles, drilled steel pipe pile and pile hole precast concrete piles are substituted. Prestressed reinforced prestressed concrete pipe pile with a tensile strength of not less than 1420 MPa, non-proportional extension strength of not less than 1280MPa. Pile steel bar for prestressed concrete, because of its high strength, high prestressing of the lower reinforcement of concrete pipe pile that can meet the design requirements of bending properties, which only requires reinforcement ratio of not less than 0.4% i.e. can. In order to pursue the production of high-strength concrete, reducing the production cost is low, prestressing steel are often super-tension phenomenon, the compressive strength of concrete pile is easier to meet product standards. Prestressed concrete square pile design there is also a low ratio of reinforcement problem, there is also the production of ultra-tensioned prestressed phenomenon. The concrete is a typical brittle material, a high modulus of elasticity, compressive and tensile correspondence to the radio. Reinforcement ratio and ultra-low tension, resulting in significantly increased brittleness pile, transportation, during pile driving Pile chance of brittle fracture is significantly improved. In addition, with the recent in-depth study of prestressed concrete pipe piles and piles of prestressed concrete square, their level of capacity, particularly horizontal bearing capacity of prestressed concrete pipe piles have different views. Therefore, national and some provincial standards or regulations made Atlas, the scope of prestressed concrete pipe pile non-seismic area and the seismic intensity of 6 degrees, 7 degrees in the area, if used in the seismic intensity of 8 degrees in the region, the to be subject to checking; or should not be used in areas where seismic intensity of 8 degrees.