mohammad afrooznia

High-performance reinforcement concrete due to its ductility and higher energy absorption has many applications in the field of passive defence than the normal concrete. These high-performance materials can be used in many cases, such as seismic improvement of building members. In some cases the structural capacity is increased, which is called strengthening. Strengthening can be carried out by increasing the toughness and increase of resistance. In this study, the use of Explosion Proof concrete in order to protect the structural components (in this study: Weak-one Slabs). In this paper, four weak-one way slab that were strangled in various zones have been studied. The numerical modelling is proceeding in Abaqus / explicit. For modelling the behaviour of concrete, CDMP method has been used. The results of this study show that the energy absorption in the strengthened slab in the tense region has increased to seven times compare to other zone of strengthening. The use of fiber reinforced concrete has a significant effect on the increase of bearing capacity and the ductility of a one-way slab. In other words, the use of high-performance fiber reinforced concrete as a method for the strengthening of structural elements such as slabs will be effective in improving the behaviour of them, especially in the field of passive defence. Also, the maximum tolerable explosive load in compression, tensile and compression-tensile strengthed zone specimens was 1.3, 0.85 and 1.21 times compare with the reference specimen. The results of this study show that the use of high-performance fiber concrete laminates in all zones of the slab simultaneously, increase stiffness and reduce the deflection of the specimen.

One of the important subjects in the concrete structure field is rehabilitation. The goal of rehabilitation is made equivalent between the structural capacity and the seismic demand of it. In some cases, the structural capacity should be increased so that it equals to the seismic demand. This increasing structural capacity is called strengthening. The strengthening is including two By increasing stiffness (adding bracing, shear wall etc.) or increasing strength (steel jackets etc.). One method of strengthening is the approach of using a special concrete with high capabilities. Experimental studies have been carried lately about strengthening with HPFRCC on beams, columns, slabs and the other structural elements and the strength of this concrete has been confirmed in strengthening. In the following, the experimental study on strengthening of weak one way slabs with precast high performance fiber concrete laminates will be investigated. In this paper, we use HPFRC laminates. The location of laminates is the variable parameters, too. The aim is reaching the best method of strengthening weak one-way slabs with HPFRC. The experimental evidences show that using high-performance fiber concrete laminates is caused to increase bearing capacity (about two times larger than the reference slab), absorbed energy (about three times larger than the reference slab) and ductility (about twenty times larger than the reference slab). In addition, pasting the laminates into tensile, compression and sides' zone of the RC slabs has the best result.