Diagnosis and Intervention Criteria in Slabs Damaged by Severe Corrosion of Prestressed Joists

Abstract

This research defines diagnosis criteria in RC one-way slabs with severe corrosion at the lower prestressed reinforcement of the joists and proposes specific actuation criteria and constructive recommendations to increase safety. The corrosion of this reinforcement is the most common damage in building structures, and the use of aluminous cement in the precast joists can aggravate the corrosion. The usual cases of entire residential buildings with different degrees of damage and with a few or all joists affected in a slab have been simulated. American Concrete Institute load test for existing structures is used as an acceptance criterion in the simulations, and a ratio between the ultimate load and the service load is defined as a valuation coefficient. In this way, the residual safety for a damaged structure is known. Results are in accordance with extensive experience in real intervention cases, which often still have high safety reserves.