Question

For maximum sagging bending moment at
support in a continuous RC beam, live load
should be placed on

• A. spans adjacent to the support plus alternate spans
• B. all the spans except the spans adjacent to the support
• C. spans next to the adjacent spans of the support plus alternate spans
• D. spans adjacent to supports only

Answer 1

The correct option is C spans next to the adjacent spans of the support plus alternate spans

The maximum moment or shear force at a section depends on the position of the live load.

(i) For maximum positive span moment at mid point, load that span and all other alternate spans.

(ii) For maximum positive support moment, unload the spans on either side of the support and load the next spans
.
(iii) For maximum negative span moment at mid point, load the adjacent spans on either side of the span and all other alternate spans.

(iv) For maximum negative moment at support, load the two spans adjacent to the support and all other alternate spans.

For case (i)



For case (ii)