Tower Crane Foundation Design Calculation Example Link !link! Site

q_max = (V_total / A) + (M / Z) Where Z = section modulus = (B * L²) / 6.

Introduction Tower cranes are the backbone of high-rise construction. However, a tower crane is only as reliable as the ground it stands on. A catastrophic foundation failure can lead to loss of equipment, project delays, injuries, or fatalities. Unlike standard building foundations, tower crane foundations are subjected to extreme overturning moments, torque, and horizontal forces. tower crane foundation design calculation example link

Soil pressure at face (linear distribution): q_at_face = q_min + (q_max - q_min) × (distance from edge). q_max = (V_total / A) + (M /

SF = Mr / Mo = 7,650 / 4,500 = 1.7 (>1.5) → OK. Friction coefficient (concrete on soil) typically μ = 0.35. Resisting friction force = V_total × μ = 2,550 × 0.35 = 892.5 kN. Sliding force H = 150 kN. SF sliding = 892.5 / 150 = 5.95 → OK. Step 4: Bending Moment for Reinforcement Design Consider the foundation as an inverted cantilever. Critical section at face of mast base plate (assume 1.5m × 1.5m mast plate). For a 6m pad, the overhang from mast face to edge = (6 - 1.5)/2 = 2.25 m. A catastrophic foundation failure can lead to loss

Lever arm (distance between two bolt rows) = 1 m. Tension force per bolt pair = 4,500 / 1 = 4,500 kN / pair. Per bolt = 2,250 kN. This is too high – thus, increase bolt size or embedment.

But for simplicity, use factored ULS load: M_Ed = (q_average * overhang²) / 2 ... In detailed design, we use trapezoidal distribution.

For practical example: Assume maximum factored pressure = 196 × 1.5 = 294 kPa (ULS). Overhang = 2.25 m. M_Ed per meter width = (294 × 2.25²) / 2 = 744 kNm/m.