Shear Stresses in R.C.C. beams

Shear Stresses in R.C.C. beam (Reinforced cement concrete beam), Stress Based Approach (Elastic Theory), IS Code Approach SHEAR STRESSES IN R.C.C. BEAMS Stress Based Approach (Elastic Theory) R.C.C. is a composite materials so the exact shear distribution as per elastic theory is very complex. It is shown in Fig. 5.2(b) by the hatched portion of the curve.It is parabolic in the compression zone with zero at the top and maximum at the neutral axis. The value of shear-stress is constant in the tensile zone and is equal to the maximum shear-stress (q) because the concrete, below the neutral axis (tensile zone) is assumed to be cracked and neglected. The maximum value of shear stress (q) as per elastic theory is given by \[q=\frac{V}{bjd}\] where             V = shear force at the section b and d = dimensions of the section j = Lever arm depth factor IS Code Approach As per IS code…

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Characteristic Strength of Materials Characteristic Load or ultimate load
Characteristic Strength of Materials

Characteristic Strength of Materials Characteristic Load or ultimate load

Learn : Characteristic Strength of Materials :Characteristic Strength of Concrete, Characteristic Strength of Steel. and Characteristic Load or ultimate load CHARACTERISTIC VALUES  (REFER CLAUSE 36, IS CODE) Characteristic Strength of Materials The characteristic strength is based on the statistical analysis of the test results because there are variations in the strength of the material used. In order to simplify the analysis, it may be assumed that the variation in strength follows a normal distribution curve which is symmetric about the mean value as shown below in Fig. 3.1. Therefore, characteristic strength = Mean strength - k S where S is the standard deviation, k=1.64, corresponding to 5% probability \[\therefore                f_{ck}=f_{m} - 1.64 S\]  Characteristic Strength of Concrete The term characteristic strength means that value of strength of material below which not more than 5% of the test results are expected to fall. It is denoted by fck is N/mm2. The value…

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comparison of working stress method and limit state method

Learn : comparison of working stress method and limit state method, working stress method,Drawbacks of the working stress method, Limit state method :  Limit state of collapse, Limit state of serviceability. COMPARISON OF WORKING STRESS METHOD AND LIMIT STATE METHOD Working Stress method and Drawbacks of the working stress method Working Stress method This method of design was the oldest one. It is based on the elastic theory and assumes that both steel and concrete and elastic and obey Hook's law. It means that the stress is directly proportional to strain up to the point of collapse. Based on the elastic theory, and assuming that the bond between steel and concrete is perfect, permissible stresses of the materials are obtained. The basis of this method is that the permissible stresses are not exceeded any where in the structure when it is subjected to worst combination of working loads. In this method, the…

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