Abstract

This paper aims to propose a monitoring strategy for the assessment of the efficiency of polyurethane resin injection as a treatment technique in damaged masonry structures. The polyurethane resin injection technique is mainly adapted in repairing shallow foundations by densifying the soil and increasing its bearing capacity. Since the distribution path of this expansive resin into the soil is not well known, it makes it difficult to avoid further structural damage to the buildings. In order to avoid these kinds of additional damages on a cracked masonry structure, a field measurement technique was adapted during geotechnical remediation operations. Fiber Optic Sensors (FOS) were installed on four angles of the building in order to measure the local micro strains of the walls as well as the existing cracks dynamics (openings/closings). A geotechnical investigation survey was also carried out both at laboratory and field scale before and after the treatment process. The mechanical properties of the soil were investigated before and after the remediation process using in-situ dynamic penetrometer test (PANDA test). Results showed that fiber optic sensors are able to capture indirectly the improvements of soil properties in crack dynamics.