4.1 Experimental Analysis

The experimental work is carried out to evaluate the shear strength of steel fiber reinforced concrete deep beams without stirrups. For this 18 beams are cast. The beams are tested under two-point loading as per IS after 28 days curing. Fiber fraction is varied as 0%, 1.5% and 3%. The shear span-to-depth ratio (a/d ratio) for beams is kept as 0.60 for case-I and 0.74 for case-II. The cube compressive strength is estimated. The experimental results are compared with theoretical results obtained from empirical equations and design codes. Also the experimental results are compared with the equations put forth by the other researchers

*…show more content…*

For the tabulation values please refer annexure 5. Figure 4.6: Ultimate Shear Stress of Concrete with respect to Fiber Content From the figure 4.6, it is observed the maximum value of ultimate shear stress 6.131 N/mm2 is observed at 3 % of fiber content and shear stress increases with increase in fiber content.

4.4.3 The Ultimate Shear Stress of Concrete with respect to a/d Ratio and % Fiber Content. The ultimate shear stress of concrete with respect to a/d ratio and % fiber content is presented in figure 4.7. For the tabulation values please refer annexure 6. Figure 4.7: Ultimate Shear Strength of Concrete with respect to a/d Ratio and % Fiber Content

From figure 4.7, it is observed that ultimate shear stress is directly proportional to percentage fiber content and inversely proportional to a/d ratio. Therefore we can see that as the % fiber content increases the ultimate shear stress increases also as the a/d ratio decreases the ultimate shear stress increases.

4.4.4Percentage Increase in Ultimate Shear Stress Results of percentage increase in ultimate shear stress are presented in table

*…show more content…*

Maximum percentage increase in ultimate shear stress is 48.27%.

4.5Cracking Shear Stress

4.5.1 Cracking Shear Stress for Case-I Results of cracking shear stress for case-I of size 90 mm wide and 360 mm deep having clear span of 600 mm are presented in figure 4.8. For the tabulation values please refer annexure 6. Figure 4.8: Cracking Shear Stress with respect to Fiber Content From the figure 4.8, it is observed that, the maximum value of cracking shear stress 4.09 N/mm2 is observed at 3 % of fiber content and cracking shear stress is directly proportional to % fiber content.

4.5.2 Cracking Shear Stress for Case-II Results of Cracking shear stress for case-II is presented in figure 4.9. For the tabulation values please refer annexure 7. Figure 4.9: Cracking Shear Stress of Concrete with respect to % Fiber Content From Figure 4.9, the maximum value of cracking shear stress 3.827 N/mm2 is observed at 3 % of fiber