Determining patterns of the deformed state of the transport concrete pipe reinforced with a metal clamp under the action of static load

Abstract

The object of this study is a concrete pipe and a pipe whose integrity was restored using a metal clamp while filling the layer between the existing pipe and the metal clamp with self-expanding concrete mortar. It has been established that the most common types of defects and damage to pipes on the roads are transverse and longitudinal cracks, as well as concrete chipping and spalling. A procedure has been devised to test experimentally a new concrete pipe without reinforcement and a concrete pipe reinforced with a metal clamp under static load. Experimental tests of the concrete pipe without reinforcement and with reinforcement with a metal clamp were carried out in the laboratory. Digital indicators, an analog-to-digital converter, and a personal computer were used to measure pipe deformations. It was found that the maximum value of vertical deformations of a new concrete pipe before cracking was 4.75 mm, and that reinforced by a metal clamp – 4.36 mm. At the same time, the maximum deformation at which the destruction of the new pipe occurred was 6.36 mm, and that of the reinforced pipe with a metal clamp – 10.51 mm. It was established that the reinforcement of the destroyed pipe with a metal clamp in the initial period of loading leads to detachment of the clamp from the concrete of the pipe. Further, when the clamps are included in the work, there is a stable operation of the concrete pipe and the amount of growth of pipe deformations increases smoothly. The results of measuring vertical deformations at the top of the pipe without reinforcement and with it showed different deformation values. It was established that the complete destruction of the pipe with a reinforced metal clamp takes place during deformations 61 % higher than the deformation at which the non-reinforced new concrete pipe is destroyed. It was found that one of the methods of restoring the bearing capacity of damaged and defective pipes in the road industry is the use of metal clamps