Today, many buildings of concrete in Iran and the world have been in operation for more than a decade and have been damaged for many reasons and need to be retrofitted. Considering that the replacement of these buildings has been costly and has no economic and environmental justification, due to the increasing need of engineers and construction industry experts to reinforce, repair and improve concrete structures, several different methods have been proposed for this issue. Is. One of the strengthening methods is the use of special concrete with high capacity and high performance.one of these concretes is HPFRCC.
Strong fiber reinforced concrete cement composites (HPFRCC) are used for materials including cement mortar with fine aggregates and fibers. The characteristic feature of this material is that, unlike ordinary concrete, it exhibits strain hardening behavior under tensile loading. In this Article, HPFRCC layers of different thicknesses are used to reinforce the flexural strength of weak concrete slabs. Using finite element method, the numerical strength of HPFRCC layers on these slabs is investigated. The results indicate that the bending strength of the slabs with HPFRCC improves resistance and also improves the shape of the slabs.or the application of finite element method to the numerical investigation of the resistance of the HPFRCC layer on this slabs been paid.