PSI - Issue 59

Vitalii Kovalchuk et al. / Procedia Structural Integrity 59 (2024) 360–366 Kovalchuk, Parneta & Rybak / Structural Integrity Procedia 00 (2019) 000 – 000

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Following the installation of the packers, the cracks were sealed using Sikadur Combiflex CF Adhesive Normal epoxy glue to prevent any leakage of the epoxy material during the injection process and to secure the packers in place (Fig. 3). Once the epoxy glue reached the necessary strength, the cracks were subjected to injections. Before injecting the epoxy material under pressure, the integrity of the cracks was verified. This involved supplying compressed air, followed by the introduction of the epoxy mixture. The injection process was carried out from the lower packer 1 (Fig. 3), while the other packers remained open.

Packer 2

Packer 1

Solution supply by pump

Fig. 3. The process of injecting cracks with a solution.

Once the solution emerged at the next packer, the supply of the solution was halted using shut-off valve mechanisms. Packer 1 was then sealed, allowing the solution to be directed to the subsequent packer 2 , and this process continued sequentially, injecting the cracks around the circumference of the pipe. After achieving the intended strength with the solution, the packers were disassembled, and the surface of the structure was restored. Following these procedures, the integrity and load-bearing capacity of the concrete pipe were fully restored. 2.3. The experimental measurement method for evaluating the deformability of a concrete pipe Experimental studies were conducted under laboratory conditions to assess the deformations of a concrete pipe restored through the injection of an epoxy solution into the depth of cracks.The diagram and equipment for measuring pipe deformations are shown in Fig. 4.

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1

2

3

PC with measurement data collection software

Analog-to-digital converter

Press P-250. Diagram of the location of digital sensors on the pipe

Digital sensor

Fig. 4. Scheme for measuring the deformed state of a restored concrete pipe during tests.

The load from the press on the pipe was set stepwise, with a value of 50 kgf with using the P-250 press. At each stage of loading, the shutter speed was 5 minutes. Static tests were conducted on a concrete pipe that had undergone