Rehabilitation of Damaged Pier-Pile Joints in Tooz Bridge Using RC Confined By Steel Casing

Abstract

Over the past years, Tooz bridge has been subjected to severely torrents led to erosion and collapse of soil at pile heads during execution, causing some damages to the heads of piles (joint between the pier and the pile) and its aspects.
Technical reports indicated that the piles are implemented in diameter of (150 cm) with depths ranging from (12m) to (15m) and these ranges are more than what is required if we take into account soil capacity in this depths is over (20 ton/m2), and the maximum capacity is within limits that are designed for. Test results indicated that the concrete of piles have a compressive strength of (31 MPa) to (59 MPa) with ultimate pile capacity ranged from (600 tons) to (720 tons) with deflection not exceed (5mm). The site surveys records deviations in location and coordinates of some piles (in varying degrees) in the longitudinal and transverse directions. After technical meeting
between the constructing company and the consultant team, two methods for treatment have proposed, the first method is construct of pile cap around the damaged joints, while, the second method is using RC confined by steel casing. To save the time and cost, and to minimize the dead loads on piles, the second proposal is adopted and the structural analysis indicated that the used method is saved.