Live Demo — Concrete Pedestal Foundation Calculator
Enter your pole, mounted equipment, wind speed and soil data to size the buried concrete pedestal and verify overturning, bearing and anchor bolt checks.
Concrete Pedestal Foundation Calculator
Free professional concrete pedestal foundation calculator for solar street lighting poles. Input the pole geometry, mounted equipment, 50-year-return wind speed and soil bearing capacity to back-calculate the pedestal size, verify the overturning safety factor, anchor bolt tension and base bearing stress, and get concrete volume plus reinforcement guidance.
Key Features
Pole Parameters
Set the pole total height, tapered or cylindrical type, top/bottom diameters, wall thickness and pole self-weight to define the structural column.
Mounted Equipment
Enter lamp head, solar panel and battery box weights, windward areas and mounting heights, plus the lamp arm extension, for accurate load distribution.
Environment Parameters
Input the 50-year-return maximum wind speed (typically 60-85 mph inland, 94-107 mph in typhoon zones) and the shape coefficient for members or panels.
Foundation Parameters
Define soil bearing capacity, square or circular pedestal, side/diameter, buried depth and anchor bolt circle diameter to model the buried block.
Overturning & Bearing Checks
Verify the overturning safety factor K_ov (required ≥1.5) and the maximum base compression stress against 1.2 × allowable soil bearing capacity.
Anchor Bolt & Materials
Compute the maximum tension per anchor bolt, get a recommended bolt spec (e.g. 4×M22), and see concrete volume plus a reinforcement suggestion.
Technical Specifications
| Platform | HTML5 Web App | Android (via WebView) |
| Core Calculation | W_k = V²/1600; K_ov = (G_base + G_upper) × (B/2) / M_total ≥ 1.5 |
| Pole Height | 3 - 100 ft (tapered or cylindrical) |
| Wind Speed | 45 - 135 mph (50-year return) |
| Shape Coefficient | 0.7 (member) / 1.2 (flat panel) |
| Soil Bearing Capacity | 1,000 - 10,500 psf (clay 2,100-4,200, sand 3,100-6,300) |
| Pedestal Size | 1.6 - 9.8 ft side/diameter; burial depth ≥ H/7 |
| Anchor Bolts | Bolt circle 8 - 40 in; 4×M22 grade 6.8 typical |
| Industry Standards | EN 40-5, EN 1991-1-4, EN 1992-1-1, EN 1993-1-1, AS/NZS 1170.2 |
| Output | Overturning safety factor + status, bolt tension + spec, bearing stress + status, concrete volume + reinforcement |
Frequently Asked Questions
How is the overturning moment calculated?
The calculator first finds the basic wind pressure W_k = V²/1600, then computes the wind force on each component F_i = W_k × C_s × S_i and its moment M_i = F_i × H_i, and finally sums all contributions (pole, lamp, solar panel and battery box) into M_total for the overturning check.
Why must the buried depth be at least 1/7 of the pole height?
A deeper burial increases the pedestal self-weight and the lever arm (B/2), both of which raise the overturning safety factor K_ov = (G_base + G_upper) × (B/2) / M_total. The 1/7 rule is an experience guideline; in permafrost regions the base must sit below the frost depth instead.
What does the overturning safety factor K_ov mean?
K_ov is the ratio of the stabilizing moment (pedestal plus upper structure weight acting at half the base width) to the wind overturning moment. It must be at least 1.5; for example, enlarging a 900×900×1200 mm block to 1100×1100×1200 mm lifts K_ov from 1.27 (fails) to 2.27 (passes).
How is the anchor bolt size determined?
The maximum bolt tension is approximated as T_max = M_total / D_bolt for a 4-bolt square layout, or T_max = M_total × Y_max / ΣY_i² for the precise method. This value must stay below the bolt allowable tension — an M22 grade 6.8 bolt allows about 52 kN (11,690 lbf), which is how the calculator picks the recommended spec.
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