PSI - Issue 60

Harikrishna S et al. / Procedia Structural Integrity 60 (2024) 700–708 Harikrishna S / Structural Integrity Procedia 00 (2019) 000–000

707

• All damaged reinforcement bars were cleaned /brushed off /cut to bare metal. Additional reinforcement bars were provided in places of deteriorated/ removed bar locations and was tied to old rods (ensuring proper development length is available). Welding was not an option as sulphur vapour cloud may be present inside pit. A corrosion resistant protective Coating was applied over the reinforcement bars for better corrosion resistance in a corrosive environment. • An epoxy bonding agent was applied over the surface of old concrete to ensure proper bonding of repair concrete over old concrete as a special application. • The wall was refurbished to original dimensions using micro concrete. The repair was done in 3 stages (lift by lift). Micro concrete repair mortar was applied along with 6mm chips. A corrosion inhibiting admixture was also added to repair mortar as additional special material.

Fig. 11. Fixing new reinforcement bars & casting new brick wall

• New refractory brick lining was provided on both sides of the walls. The brick work was done in stage by stage of 1m height. • The joints of all walls (old & refurbished) were raked open using a mechanical grinder and the joints were cleaned to remove all loose particles/ materials. Then they were filled up using mortar joint (furan based adhesive compound) to seal the joints. • The damages in the top slabs were also repaired. The cracks in top slab were repaired using thixotropic repair mortar (special material). The damaged reinforcement rods were replaced with new bars. The locations of spalled concrete were repaired using same repair mortar. A layer of plaster was provided over bottom portion of slabs which had repairs. After placing the slabs, the gaps were filled with thermocol sheet from top of slab and sealed with a layer of neat plaster over the same.

Fig. 12. New brick walls after casting.