【Construction life】Reinforcement material single check 2-column reinforcement check

For buildings with raft foundation as the structural foundation, the second type of reinforcement to be used is column reinforcement. The column reinforcement is different from the plate reinforcement and does not need to be measured all the time. As for the check, what are the key points?

If you haven't seen the steel bar check, you can read this article first: [Life on the Construction Site] Reinforcement material list check 1-version bar check , after all, the raft foundation steel bar binding has a certain order, and we check according to this order. Come on, it will not be messed up. When you do a project, the successive homework will definitely affect each other. If you want to know what the later work item affects the previous work item, then you must be familiar with the previous work item. So, follow the order. Bar.

Check steps

Before checking, let’s review, for the prep work of picking materials in the basement, you must first tell the pickers the height of each pouring, and they will know how to help you with reinforcement. It is about the reserved length of the steel bar. If You want to change the concrete pouring elevation without telling the pickers that the steel bars will be covered by the concrete, so you are slowly looking for your steel bars (that means no one should talk about it like that).

The same is to first check the construction drawings and check the bill of materials:

construction drawing

The steps are similar, as listed below:

1. The number of columns and bars is different from the structure diagram
2. Check the length of the bar hook
3. Check the misconnection distance of column reinforcement
4. Check stirrup and tie size
5. Check the number of stirrups and tie bars

1. The number of columns and bars is different from the structure diagram.

There is no overlapping problem of the column reinforcement. No matter what kind of drawing, it must be checked whether it is the same as the structure drawing. As in the previous version of the reinforcement check, the first step is to check the lap length, extension length and structural standard. Picture 1 is different. The part of the column reinforcement is to check the number of steel bars. It is different from the structural drawing. We must check the structural drawing during construction on site. The construction drawing is for the workshop to see, so this part needs to be checked. Check first.

There will be column numbers on the construction drawings. Just take the column numbers and pairs on the corresponding structural drawings. For example, the number of main bars in the picture above is 28, and the structure and construction are both 28, so there is no problem. This part is very Make fewer mistakes, unless the person picking materials is really tired. Picking materials is really not done by people. The head must be very clear. Just because it is very tired, we need to help detect errors to reduce the number of changes during construction.

2. Check the length of the hook of the column reinforcement

The diameter of the #8 steel bar is 2.54cm, and 12 times the diameter is 30.48cm. In principle, it is enough to pick up 35 cm. However, the steel bar processing factory will not help to process the numbers at the end of 5, so unconditional rounding will pick up 40 cm. The diameter of #10 steel bar is 3.226 cm, 12*3.226=39.192cm, which is also 40 cm. You said why the #8 steel bar can't be rounded up to pick up a 30 cm hook. I'm sorry, this kind of thing can only be more, not less.

↑ The pickers usually mark the length of the hook of the column bar on the construction drawing. For example, this picture is the #8 main bar, and the red circle mark is the hook length of 40 cm.

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3. Check the misconnection spacing of column bars

The standard for the staggered spacing of columns and bars is 60 cm, and the surrounding area cannot be continued. In vernacular, it is: between two floors, only the middle section can be continued, and no other can be connected. This matter is in this article: [Life on the Construction Site] How to Memorize the Lap Length and Rebar Picking❘ The specifications for each rebar have been explained, but we are reviewing it once, and the picture is clearer.

↑Assuming that the net length of the column is 400 cm, the upper and lower 1/4 cannot be connected, which means that only the middle 200 cm can be connected. Generally, the height of the building will not be so high. This is just an assumption, don't be too serious.

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↑The wrong connection distance should be 60 cm, which will also be displayed on the construction drawing, the position marked by the red circle.

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4. Check the size of stirrups and ties

The size of the stirrup root tie will be related to the size of the column itself. In principle, if the size of the column is 100*100 cm, the stirrup will be 90*90 cm, which is related to the requirement that the column protection layer should be 4 cm. Grab the whole number, so it is 5 cm on one side and 10 cm on both sides.

The part of the tie will be one centimeter more than the stirrup. I am not very clear about the reason. Maybe it is too tight and it will not fit in. I will ask for the material and share it with you when I have time.

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5. Check the number of stirrups and tie bars

This part is the total spacing/each spacing, and you will get the number of counts. It should be noted that some structural drawings will be divided into the surrounding area and the non-bundling area, and the spacing of stirrups is different. rebar.

If there is less steel, you need to replenish the material. I have made a mistake in this area. It costs a lot of money to replenish the material. You have to figure out how much material is missing. Because you usually have to make up for the lack of material, you will call the straight material. Make up, and then ask the steel binding manufacturer to process it for you on site. The part of the cost will be an additional shipping fee, and a processing fee for the rebar binding manufacturer. In short, it is a waste of your boss's money.

Bill of Materials

The bill of materials for the column bars is relatively simple, and the length types will be much less. It is recommended to print out the picture when it is right, and draw it after statistics, so that you will not mess it up. This step is just a stupid effort. You can do it with patience, don't lie to me that you can't finish a lot of things, unless you are a laborer, you just don't want to do it.

Epilogue

After the column is finished, the next step is to make the beam. In the next article, we will share the method of checking the beam reinforcement.

The engineering-related articles I wrote are all organized in this " Engineering Series Articles ", and will continue to be updated in the future, I hope to be helpful to you.

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I'm Mr. Engineering, a little engineer working in the construction industry. Construction industry is an industry with very closed information. Most of all experience can only be passed down by the industry. I hope to do my best to share the knowledge and life of the industry with everyone. If you have any questions about the content of the article, please let me know by leaving a message below. If this article can help you answer, please help me clap five times.

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