26 Feet Beam Structural design

Added: 2026-05-25

[00:00:00]Welcome back to Civil Engineers YouTube channel. In this video lecture, I would like to guide you for 24 ft span of beam reinforcement details. You can see the diagram. We have two columns. The span between two column is 24 ft. What should be the size of beam and inside steel reinforcement? This is for commercial building up to two story, G+1 story. So, this is the topic for today. If you are new on this channel, so you may like this video and subscribe the channel for more civil engineering updates. First of all, remember guys, this beam is designing for First of all, design for two story. It means G+1, ground floor plus one.

[00:00:50]But, I did from my personal experience and I already did this design for one of my client. So, therefore I'm guiding you properly and I did the design. I'm just giving you some related information for this beam, okay? For G+1, but this is commercial, okay?

[00:01:09]Commercial building.

[00:01:12]So, therefore guys, the size of the beam should not be less than as I did.

[00:01:17]12 in x 18 in x This is size of the beam. Inside, we required four numbers of steel rods at the bottom, two at the top, and two are side bars.

[00:01:36]But, just at the length of L by 3. This is for G+2, but we already did factor of safety. So, you can go up to G+3, okay?

[00:01:47]But, for the factor of safety, I did G+1.

[00:01:51]So, therefore guys, here let me create the stirrup here like this.

[00:01:57]And here like this.

[00:02:00]Okay. So, you can see size is size of beam which is 12 in by 18 in. So, you with eight bars.

[00:02:17]So, here remember guys, we required here four bars at the bottom.

[00:02:22]Four bars and the dia is 16 mm.

[00:02:27]Okay? And two bars at the top dia is 16 mm.

[00:02:34]And two are side bars.

[00:02:36]Two bars side bars and the dia is 16 mm.

[00:02:42]Okay?

[00:02:43]Remember these two bars are provided here guys, you can see this green color can you show you the steel reinforcement. So, we have here this one. You can see we have here four bars.

[00:02:56]And the dia is 16 mm. And here the top we have guys two bars dia is 16 mm.

[00:03:04]Next guys, here we have two side bars at the distance of L by 3.

[00:03:09]L by 3 at this side, L by 3 at this side. So, you can say at the length of or at the span of you can see at the span of 8 ft and 3 in. So, you can see and also 8 ft and 3 in. So, you This is two side bars and the dia is 16 mm. Remember guys, here we have this development length and the top one is coming to the downward side. So, this length should not be less than 12 in.

[00:03:39]So, And also the top one and these steel reinforcement are the development length should be connected with the longitudinal bars of the column like this.

[00:03:53]Right? So, next guys, if you require to provide to provide lapping length. So, the lapping is allowed at the top of the middle. Guys, you can see at this place you can provide the lapping length, but lapping is not lapping should not be provide at the bottom steel reinforcement. So, you are not allowed to provide the lapping here.

[00:04:14]So, here I'm talking about the lapping.

[00:04:16]Lapping is not allowed here at the distance of L by 4. It is It should be provide at the junction between beam and column. Okay? And also, if you require at the middle, so don't provide the lapping at the middle, but at the top portion it should be provide at the distance of L by 2. So, this is about lapping. So, now let me guide you for steel reinforcement. So, provide Here guys, you can see bottom bars.

[00:04:42]Four bars, 16 mm.

[00:04:45]Top bars, two 16 mm.

[00:04:50]Side bars at the distance of L by 3, two bars, dia 16 mm.

[00:04:57]Now, let me guide you for the stirrups.

[00:04:59]So, here stirrups dia should be 8 mm with the spacing of 6 in.

[00:05:09]Sorry.

[00:05:11]4 to 6 in.

[00:05:13]For at the distance of L by 3, provide at the 4 in. And after L by 3, guys, you can see you can increase it to 6 in. So, this is for the stirrups. Next guys, you can see these hooks. You can see these one.

[00:05:29]It should be bent on 135°.

[00:05:32]R 135° and the length of the hook should not be less than 3 in.

[00:05:39]This is also very important. Next guys, concrete cover.

[00:05:43]It should be 1.5 in for all sides, bottom, top, left and right side. Next one guys, remember the other one, M use M20 grade concrete, okay? M 20 grade concrete.

[00:05:59]We are M20 grade concrete concrete ratio is 1:1.5:3.

[00:06:04]One part cement, 1.5 part sand, and three parts crush are aggregate. So guys, this is the some important details related RCC beam if the span is up to 24 ft. So these are the steel reinforcement. Two at the bottom, two at the top, two are side bars. Grade of concrete top bars dia, side bars dia at the distance of L by 3. So this is for commercial building. Hope this short video can help you. Thanks for watching. See you in next video. Goodbye.