Base Plate Design For Steel Column

For s275 steel and t bp 40 mm base plate yield strength f y bp r eh 255 n mm 2 base plate ultimate strength f u bp r m 410 n mm 2.

Base plate design for steel column.

N d 2 3 in b bf 2 3 in 2. Friction between base plate and the grout or concrete surface n u c c v p f a m 0 2 the friction coefficient m is 0 55 for steel on grout and 0 7 for steel on concrete 2. First the area of the plate is calculated based on the allowable beating stress defined by the following equations. It also supplements simple connections part 1 of the existing asi.

Design of base plate with shear four principal ways of transferring shear from column base plate into concrete 1. Design guide 7 covers the pinned column base plate connection. In this case the base plate may be designed as follows. The graphics show the column the baseplate grey and the effective area yellow overlay.

Concrete for concrete grade c30 37 characteristic cylinder strength f ck 30 mpa 30 n mm 2. Determine plate cantilever dimension m or n in direc tion of applied moment. M n 0 95d 2 n b 0 80bf 2 3. Such column bases are usually assumed to be subject to axial compression and shear only.

Baseplates for circular and square hollow sections must be square. Width of base plate depth of the column section 2 thickness of gusset plate 80 mm to 100 mm. Select a convenient width of the base plate. F cd α cc f ck γ c f cd 0 85 x 30 1 5 17 n mm 2.

I divide the factored column load by the design bearing strength of concrete and find the area of the base plate. The bolts are cast into the concrete base in location tubes or cones and are fitted with anchor plates to prevent pull out. 0 35 f c a 0 70 f c. 2 september 2002 design of.

Design guide 7 provides a recommended design model for pinned base plates for both open and closed column sections subject to compression and tension actions and completes the revision of structural steel connections 4th edition 1994 often referred to as the green book. The recommended design model draws extensively on the american institute of steel construction steel design guide 1 base plate and anchor rod design second edition and on the australian steel institute publication steel construction vol. B 4 1 design procedure for a small moment base 1. The aisc manual of steel construction reference 3 provides a two step procedure for the design of axially loaded base plates.

High strength grout is poured into the space below the plate. In addition to selecting the column and the grade of concrete the user must select the size thickness and steel grade of the baseplate. Typical column bases as shown below consist of a single plate fillet welded to the end of the column and attached to the foundation with four holding down bolts.