To understand steel construction drawings, you should study systematically, step by step, starting with the most basic ones. Whether it is a drawing of ordinary steel bars or a drawing of prestressed steel bars, there are drawings with different sections and sections, and you have to read them accordingly.

How to quickly understand steel bar drawings:

1. How to express stirrups:?

⑴ φ10@100/200(2) means stirrups are φ10, the spacing between encrypted areas is 100, and the spacing between non-encrypted areas is 200, all are double-limb hoops. ?

⑵ φ10@100/200(4) means that the stirrups are φ10, the spacing between dense areas is 100, the spacing between non-densified areas is 200, and all are limb hoops. ?

⑶ φ8@200(2) means the stirrups are φ8, the spacing is 200, and the stirrups are double leg hoops. ?

⑷ φ8@100(4)/150(2) means the stirrups are φ8, the spacing between dense areas is 100, four-limb hoops, and the spacing between non-densified areas is 150, two-limb hoops. ?

1. How to express the main bars on the beam and the main bars on the bottom at the same time: ?

⑴ 3Φ22, 3Φ20 means that the upper steel bar is 3Φ22 and the lower steel bar is 3Φ20. ?

⑵ 2φ12, 3Φ18 means that the upper steel bar is 2φ12 and the lower steel bar is 3Φ18. ?

⑶ 4Φ25, 4Φ25 means that the upper steel bar is 4Φ25 and the lower steel bar is 4Φ25. ?

⑷ 3Φ25, 5Φ25 means that the upper steel bar is 3Φ25 and the lower steel bar is 5Φ25. ?

2. How to express the steel bars on the upper part of the beam: (marked on the upper support of the beam)?

⑴ 2Φ20 means two Φ20 steel bars, arranged throughout the length, for both limbs hoop. ?

⑵ 2Φ22+ (4Φ12) means 2Φ22 is the overall length, and 4φ12 is used for the six-limb hoop. ?

⑶ 6Φ25 4/2 means that the upper row of steel bars is 4Φ25 and the lower row is 2Φ25. ?

⑷ 2Φ22+ 2Φ22 means there is only one row of steel bars, two at the corners and two in the middle, evenly arranged. ?

3. Representation method of steel bars in the beam waist: ?

⑴ G2φ12 represents the structural steel bars on both sides of the beam, one φ12 on each side. ?

⑵ G4Φ14 represents the structural steel bars on both sides of the beam, two Φ14 on each side. ?

⑶ N2Φ22 represents the torsion steel bars on both sides of the beam, one Φ22 on each side. ?

⑷ N4Φ18 represents the torsion steel bars on both sides of the beam, two Φ18 bars on each side. ?

4. How to express the steel bars in the lower part of the beam: (marked on the lower part of the beam)?

⑴ 4Φ25 means there is only one row of main bars, and 4Φ25 all extends into the support. ?

⑵ 6Φ25 2/4 means there are two rows of steel bars, the upper row of bars is 2Φ25 and the lower row of bars is 4Φ25. ?

⑶ 6Φ25 (-2)/4 means there are two rows of steel bars, the upper row of bars is 2Φ25, which does not extend into the support, and the lower row of bars is 4Φ25, which all extends into the support. ?

⑷ 2Φ25 + 3Φ22 (-3) / 5Φ25 means there are two rows of ribs, and the upper row of ribs is 5. 2Φ25 extends into the support, 3Φ22 does not extend into the support. The lower row of ribs is 5Φ25, arranged throughout the length.