Installing a heavy urban bench isn't just about placing it on the ground; it requires a serious, engineered foundation for safety and longevity. The most critical element is a poured concrete footing. For a standard heavy-duty bench, a foundation at least 18 inches deep and 24 inches wide is typically the minimum. This size helps prevent frost heave in colder climates and provides a stable base to resist tipping.
The process begins with site preparation. You must excavate the area to the required depth, ensuring the soil at the bottom is well-compacted. For the concrete itself, a high-strength mix (typically 3000 psi or greater) is necessary. Embedding a steel rebar cage within the concrete significantly increases its tensile strength and prevents cracking.
Crucially, anchor bolts or heavy-duty J-bolts must be set into the wet concrete before it cures. These bolts, positioned to match the bench's leg plates or mounting brackets, are the primary connection point. Once the concrete has fully cured for at least 72 hours, the bench can be secured using oversized washers and locking nuts. For areas with high vandalism risk, consider using tamper-resistant fasteners. This robust method ensures your public bench remains a secure and permanent fixture for years to come.