In BS8110, it states that secondary reinforcement should be provided for beams exceeding 750mm deep at a distance measured 2/3 depth from the tension face. Experimental works revealed that at or close to mid-depth of deep beams, the maximum width of cracks arising from flexure may be about two to three times larger than the width of the same crack at the level of surface where the crack originally forms.
The presence of crack is undesirable from aesthetic point of view. Moreover, it poses potential corrosion problems to reinforcement of deep beams. To safeguard against these crack formation, skin reinforcement is designed on the sides of deep beams to limit the formation of flexural crack widths. Though the principal function of skin reinforcement is to control crack width, it may be employed for providing bending resistance of the section.
This question is taken from book named – A Self Learning Manual – Mastering Different Fields of Civil Engineering Works (VC-Q-A-Method) by Vincent T. H. CHU.
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What should be the bend length of skin reinforcement of 8dia bar for PCC abutment of bridge
When skin reinforcement is provided in mass plain cement concrete like abutments of minor brides can it be called reinforced cement concrete
No. It never called as RCC.