Strengthening of distressed RC slabs by using ferrocement overlay

Abstract

An ex,perimental study has been performed to know the performance of ferroeement overlay in repairing I strengthening of distressed reinforced concrete slabs. Six reinforced concrete slabs were constructed and te~ed in the laboratory for this purpose. Each slah~J\LasJe~sted_~ a one way slab will~~entrated load (lin~ load) at mid span. In each case the load~s applied incrementally and after the formation and propagation of cracks through a substantial distance, the loading was stopped and the slab was removed from the machine for rehabilitation. The slabs were repaired by ferrocement coating and precast ferro cement plates. In both cases single and double layer wire mesh were used. The precast plates were bonded with R.C. slabs by using Epoxy and in one slab bolts were also used for additional bonding. After rehabilitation, all slabs were tested in the laboratory following the same procedure as for the original slabs. The experimental results showed that depending on the method of rehabilitation 80 to 100% strength can be attained for these distressed slabs. The slab with ferrocement coating at the top and bottom of the slab showed the excellent performance, whereas the slab with bonded plates showed early failure. The influence of number of mesh layers in strengthening of distressed reinforced concrete slabs may not be known from this limited experimental study.