This study illustrated the effects of web openings through the experiment to utilize concrete strength, shear span-to-depth ratio, and width and depth of opening as test variables, and analytical comparisons with the methods proposed by Kong and
Sharp, and Tan, Tong and Tang. The results of this study are summarized as follows.
1. The width and depth of opening did not affect the mid-span deflection at initial loading stages, but it significantly affected the deflection after the occurrence of diagonal cracks. The concrete strength did not largely affect the rigidity of beams with web opening due to the existence of the web opening.
2. The slope of inclined plane to exhibit maximum crack width
decreased with the increase in concrete strength, opening size and shear span-to-depth ratio.
3. The shear strengths at initial diagonal crack and at peak were
closely related to θ3.
4. The influence of concrete strength on the ultimate shear
strength significantly decreased in deep beams with openings rather than solid deep beams. In deep beams with openings, it was evaluated that the strength of a compressive concrete strut increased at a lower rate with the increase in concrete strength.
5. The equations proposed by Kong and Sharp, and Tan, Tong
and Tang would be suitable for reinforced high-strength concrete deep beams with openings and θ3 ≥ 30◦.