Seismic retrofitting of drainage pipe openings (small to medium diameter) - "Magma Rock Method mini・NGJ"

Non-excavation sewer pipelines (small to medium diameter, φ200 to φ700) seismic resistance technology. Equipped with cylindrical stainless steel and rubber sleeves to withstand Level 2 seismic motion.

This is a non-excavation seismic reinforcement method developed to enhance the seismic resistance of the "pipe connection section where existing pipes and manholes connect," targeting pipe diameters of Ø700 or less. In cases where the connection between the manhole and the pipe does not have a flexible structure, it is known that this connection section, being in a semi-rigid state, tends to concentrate damage such as circumferential cracks or breakage when subjected to significant loads during an earthquake. This method involves pre-cutting grooves (joints) at the connection between the main pipe and the manhole, installing a mini magma, and concentrating seismic stress here to induce cracking at the joint, thereby preventing damage to the connection through its shock absorption effect. The mini magma, which is pre-installed at the locations where cracks occur along the joint, prevents the inflow of groundwater and soil into the pipe. Additionally, this seismic reinforcement method can be reliably installed even when the existing pipe is in a flowing state, as long as the water depth is 25% or less of the nominal diameter, targeting the connection between the manhole and the pipe. [Applications] ● Seismic reinforcement of the connection between manholes and pipes (circular pipes)

Sewerage facilities