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Fire Ferro cement Weir mesh Flexural strength Erroneous designNow-a-days repair and rehabilitation of the existing structures in developing countries has become solitary of the most thought-provoking tasks in Civil Engineering sector. Imperfections, fiasco and general distress in the structures can be the outcome of fundamental deficiency produced by inaccurate design, poor workmanship or overloading of the construction. It can also be instigated by corrosion, fire and natural calamities. A spoiled or distrait structure can be modernized to an acceptable level of performance at a reasonable cost by different approaches is called retrofitting. One of these techniques consists of strengthening fire damaged concrete beams by applying Ferro cement with wire mesh. Two types of Ferro cement with wire mesh are used with single layer and double layer in beam. One third point load test according to ASTM C78-02 is performed to measure the flexure performance of four specimens. The ultimate load carrying capacity for using the single layer Ferro cement strengthening, double layer Ferro cement strengthening showed an improvement of 46% and 72% respectively over the fire damaged specimens.

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RCC structures are primarily based with beams and columns. In general, the compressive strength of concrete and the yield strength of steel are specified in the design process. Compressive strength of concrete depends on a number of factors and generally shows some degree of variation from the desired strength. On the other hand, reinforcing bars with higher yield strength than that recommended in the Bangladesh National Building Code is available in the market and being used in construction. So, in practical cases, after casting the compressive strength as well as the tensile strength are not generally achieved as desired. Therefore, increase in yield strength of steel and decrease in compressive strength of concrete may have adverse effects on the flexural behavior of beams. This study includes the behavior of reinforced concrete beam due to this variation in strengths. This study shows that how certain beam behaves due to the variation of strength. Besides, reduction in ductility is also observed due to strength variation in the properties of the major constituent materials. A complete theoretical analysis along with some experimental investigation is presented in this paper.

In this study Finite Element Method (FEM) is used for analysis of crack propagation in a rectangular slab supported by peripheral beams. ANSYS Mechanical APDL 16.2 Software is used to carry out non-linear static analysis. SOLID65 solid element is used to model the continuum components. The Compressive crushing of concrete is simplified by consuming plasticity procedure, whereas the concrete cracking in tension region is found by the nonlinear physical model. The reinforcement is modeled by the smeared method and used because of the ratio of rebar implanted within the concrete slab to the whole volume of the concrete slab. The smeared reinforcement technique is more useful for the covered element such as a concrete slab. For this method it does not require explicit modeling of the rebar, For the analysis of slab much coarser mesh can be defined. The cracks appear at the top and bottom surface of the slab. The downward deflection that occurred at the underside of the slab. The spread of cracks within the slab established the system of yield line development. These results are compared with the theoretical results of yield line analysis. The cracking pattern of twoway slab that confirms the yield line analysis of slab.