Axial Load Capacities for Single Plates
Based on Gross Section Loaded Uniformly in Either Tension or Compression
Compression per AISC 9th Edition Manual (ASD)
Input Data
| Fy = | ksi | Fy = yield stress | ||
| Lc = | in. | Lc = unbraced length for compressive buckling | ||
| K = | K = effective length factor for compression |
Gross tension capacity of plate: Rt = Ft*Ap
where:Ft = 0.60*Fy and Ap = Hp*tp
| Compression (buckling) capacity of plate: Rc = Fa*Ap | |
| where: Ap = Hp*tp | |
| r = tp/(SQRT(12)) (radius of gyration for minor axis of plate) | |
| KL/r = K*Lc/r (slenderness ratio) | |
| Cc = SQRT(2*p^2*29000/Fy) | |
| If KL/r <= Cc then Fa = (1-(K*Lc/r )^2/(2*Cc^2))*Fy/(5/3+3*(K*Lc/r)/(8*Cc)-(K*Lc/r)^3/(8*Cc^3)) | |
| If KL/r > Cc then Fa = 12*p^2*29000/(23*(K*Lc/r)^2) | |
In the case of bracing gusset plates, the concept of the
"Whitmore Section" may be used to
determine the effective height of the gusset plate
to be used in analysis.
The "Whitmore Section" consists of the total
effective width at the end of the brace as determined by
drawing 30 degree lines spreading or fanning outward from the
point where the load is initially delivered to the gusset plate from
the brace and continuing to where these lines
intersect a line parallel to and at the end of the brace.
In the case of a bolted brace, this would be
from the first row of bolts to the end of the brace.
In the case of a welded brace, this would be from
the beginning of the welds to the end of the brace.
"Whitmore Section" may be used to
determine the effective height of the gusset plate
to be used in analysis.
The "Whitmore Section" consists of the total
effective width at the end of the brace as determined by
drawing 30 degree lines spreading or fanning outward from the
point where the load is initially delivered to the gusset plate from
the brace and continuing to where these lines
intersect a line parallel to and at the end of the brace.
In the case of a bolted brace, this would be
from the first row of bolts to the end of the brace.
In the case of a welded brace, this would be from
the beginning of the welds to the end of the brace.
In the case of bracing gusset plates,
the concept of the "Whitmore Section" may be used to
determine the effective height of the gusset
plate to be used in analysis.
The "Whitmore Section" consists of the total
effective width at the end of the brace as determined
by drawing 30 degree lines spreading or fanning outward from
the point where the load is initially delivered to the
gusset plate from the brace and continuing to where these
lines intersect a line parallel to and at the end of the brace.
In the case of a bolted brace, this would be from the first row
of bolts to the end of the brace.
In the case of a welded brace, this would be
from the beginning of the welds to the end of the brace.
the concept of the "Whitmore Section" may be used to
determine the effective height of the gusset
plate to be used in analysis.
The "Whitmore Section" consists of the total
effective width at the end of the brace as determined
by drawing 30 degree lines spreading or fanning outward from
the point where the load is initially delivered to the
gusset plate from the brace and continuing to where these
lines intersect a line parallel to and at the end of the brace.
In the case of a bolted brace, this would be from the first row
of bolts to the end of the brace.
In the case of a welded brace, this would be
from the beginning of the welds to the end of the brace.
Disclaimer: This calculator is not intended to be used for the design of actual structures, but only for schematic (preliminary) understanding of structural design principals. For the design of an actual structure, a competent professional should be consulted.
‘Calculations courtesy of Alex Tomanovich, PE ’