Spreadsheet for designing Doubly Reinforced Beam
Doubly Reinforced Beam is defined as the beam reinforced with steel both in tension and compression zone. This type of beam is mostly effective when the depth of the beam is constrained. If a beam having restricted depth is reinforced on the tension side only it does not contain adequate resistance capacity to resist the bending moment.
The doubly reinforced beams are applicable on the following conditions.
• If the external load is fluctuating, i.e. the load is functioning on the face of the member.
• The load is eccentric and the eccentricity of the load is varying from one side to another side of the axis.
• The member is dependent on a shock or impact or accidental lateral thrust.
• If architectural constraints exist on the beam size and the Moment to be defended is very big that a singly-reinforced beam is not suited, Doubly reinforced beam is essential.
Doubly Reinforcing the beam mainly enlarges it’s compression area that sequentially facilitates to expand area of tension reinforcement whereas control it under-reinforced. So, large Moments can be defended.
• If the reversal of load happens under wind load or earthquake load, it can result in creating tension in both lower and upper part of the beam which should be reinforced with tensile reinforcements.
Given below, the detailed spreadsheet to make the design of doubly reinforced beam. This spreadsheet is supported with various formulas which are useful to design doubly reinforced beam.
To download the sheet, click on the following link drive.google.com