What are the hazards if the ring stiffness of the carat tube is not enough? Does it cause deformations, such as buckling instability or "indentation"?
    Carat tubes have been widely used abroad and have been rated as key promotion products by the Ministry of Construction of China. It is a new type of high-quality pipeline product that promotes the development of urban stormwater sewage treatment systems: "plastic instead of plastic for steel and cement for plastic"; A new type of heavy-duty, safe, environmentally friendly, efficient, anti-corrosion, sealed, zero-leakage buried sewage "green" pipeline. After continuous R&D and innovation, the seismic fortification strength of this product is 9, which is suitable for geological areas and seismic zones with uneven settlement.

    Carat tubes have been used in burial practice for more than 50 years. After the backfill requirements are met and operated normally, there will be no deformation under normal use conditions in international/domestic applications. The reason is not that its own ring stiffness is higher than that of a rigid pipe (e.g. cast iron pipe), but is based on the principle of interaction between the pipe and the surrounding backfill.
    When a vertical load deforms the pipe, the soil around the pipe creates a horizontal support (as shown in the figure above), resulting in compressive and bending stresses in the pipe wall. The greater the flexibility of the pipeline, the greater the deformation, and the greater the lateral soil pressure reaction force on the pipe. At some stage, the vertical and horizontal soil pressures will reach equilibrium. Under the joint action of pipe and soil, the bearing capacity of the pipe itself accounts for only 15%-20%, so it is uneconomical to increase the bearing capacity of the pipe body only by increasing the ring stiffness.

    Jiecheng Plastic is a technology-based enterprise specializing in the production, R&D, sales and installation of plastic pipes, carat pipes, marine pedals and steel strip pipes.