1. Classification of Underground Fixed Base

Type A: Direct Buried Pole Type

The lower section of the main steel pole is directly buried into concrete foundation.

Type B: Embedded Anchor Flange Base

Prefabricated steel anchor frame / anchor bolt assembly embedded in concrete; main pole connected by bolt assembly (mainstream export standard).

2. Standard Foundation Dimension Parameters

General Adult Standard Basketball Stand (Arm length: 1800mm / 2250mm)

Basic pit size (minimum specification): 700 mm × 700 mm × 800 mm (L × W × Depth)

Recommended standard for school & public venues: 800 mm × 800 mm × 1000 mm

Cold frost zone (North China, Hebei area): Depth ≥ 1000 mm ~ 1200 mm (below frost line)

Note: For soft soil, backfill land or coastal windy areas, expand pit size to 1000×1000×1200 mm.

3. Concrete Technical Standard

Concrete strength grade: Minimum C25

School / high-frequency use outdoor venues: adopt C30 concrete

Bottom cushion: 100 mm thick compacted gravel for drainage

Reinforcement suggestion: Φ12 ribbed steel mesh, 200 mm spacing for large foundation; prevent concrete cracking under impact load

4. Embedded Anchor Assembly Specification (Flange Base Type)

Anchor plate material: Q235 hot rolled steel plate, thickness ≥16 mm

Anchor bolt: 4 sets M20 / M24 high-strength bolts, galvanized anti-rust

Position tolerance of anchor frame: Horizontal deviation ≤3 mm

Verticality control after installation: Pole vertical error ≤ 1‰ (no obvious tilt)

Thread protection: Cover bolt threads with grease & tape before pouring concrete

5. Anti-overturn & Safety Requirements

Anti-overturn safety factor ≥1.5; resist horizontal impact from dunking and wind load

Anti-wind standard: Meet Grade 8 wind resistance for outdoor open venues

Foundation top surface: Slight outward slope (drain away from pole, avoid ponding & rust)

Keep foundation surface 0–10 mm below finished ground level

6. Construction & Curing Standard

Excavate pit → compact pit bottom → lay gravel cushion → place anchor assembly → temporary support & vertical calibration

Pour concrete in layers, fully vibrate to eliminate air voids

Natural curing period: Minimum 7 days; do not install basketball frame before full curing. Recommended curing 10 days for outdoor projects.

Before excavation, check underground cables, water & gas pipelines to avoid damage.

7. Court Position Installation Standard

Center of foundation shall be ≥600 mm outside the court end line

Horizontal distance between pole and backboard rear: ≥1200 mm

Standard rim height: 3050 mm above finished ground

8. Common Warning & Quality Control Points

❌ Do not reduce foundation depth or concrete grade to cut cost

❌ Do not skip steel reinforcement on soft soil sites

❌ Forbid using concrete before full curing (easy foundation displacement & tilt)

❌ Low-quality non-galvanized anchor parts will rust quickly outdoors