Heavy weight concrete grades В30 (М450) are used for pipe production. At the same time, the concrete grade specified in GOST is at least B25 (M350).
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An additional increase in strength is provided by vibration compaction during casting (it reduces the number of pores and possible destruction concentrators). The method of vibropressing allows getting the exact geometric dimensions of the product and a smooth surface (with a roughness of up to 0.1 mm). This indicator reduces the tendency of pipe’s inner surface silting.
Series 3.501.1-144 Precast reinforced concrete pipe culverts for motorways and railways