Prioritized inspections of equipment at high risk of deteriorationTechnology for prioritizing manhole cover inspectionsNTT Access Network Service Systems Laboratories

We have developed a technology that enables early detection of defective manholes by estimating the condition (soundness/deterioration) of manholes based on their construction and installation environment. Manholes at high risk of deterioration are selected and prioritized for inspection, rather than using conventional uniform inspection criteria and cycles.

Currently, some manholes are beginning to show signs of aging and deterioration. In anticipation of further aging, appropriate maintenance and management is required, such as early detection of deteriorating equipment.

• FEM analysis (engineering method) was used to identify installation conditions where external forces, such as soil pressure and vehicle loads, have a significant effect on the manhole body.
• Using the Bayesian network method (statistical method), past inspection data was analyzed to illuminate the factors that had a causal relationship with the occurrence of defects.

• Manhole inspection planning

NTT Access Network Service Systems Laboratories - Civil System Project