Link - Tower Crane Foundation Design Calculation Example

The resisting moment can be calculated using the following formula:

You must obtain technical data from the crane manufacturer for both in-service (operating) and out-of-service (storm/wind) conditions. Vertical Load (V): Crane weight + max lifted load + ballast. Horizontal Load (H): Lateral wind forces. Overturning Moment (M):

To maintain compression across the entire base (preventing the pad from lifting off the soil), the eccentricity should ideally fall within the middle third of the base: tower crane foundation design calculation example link

( 279 , kPa ) > ( 180 , kPa ) → FAIL . ➜ Increase base to 5.5 m × 5.5 m and recheck.

The foundation must resist horizontal sliding caused by the shear load ( The resisting moment can be calculated using the

For those seeking step-by-step numerical examples, the following types of resources are the most reliable:

Z=B×L26=6.5×6.526=45.77 m3cap Z equals the fraction with numerator cap B cross cap L squared and denominator 6 end-fraction equals the fraction with numerator 6.5 cross 6.5 squared and denominator 6 end-fraction equals 45.77 m cubed Total Moment at Base ( Mbasecap M sub b a s e end-sub Overturning Moment (M): To maintain compression across the

You can find comprehensive structural reports and design templates at the following sources: Guide to tower crane foundation and tie design - CIRIA

Required steel area (d = 1.5 m – cover 0.075 m – 0.025 m = 1.4 m) As = M / (0.87 fy z) ≈ 783×10⁶ / (0.87×500×0.9×1,400) ≈ 1,430 mm²/m

A tower crane is essentially a giant lever; without a properly designed foundation, the laws of physics turn it into a catastrophic liability. This feature outlines the critical inputs, the design philosophy, and a simplified calculation example for a standard gravity-based foundation.

: For deeper support needs, this pile group capacity guide details the design of a 4-pile group and its connecting pile cap.