Which structural concept relies on a natural force to maintain a structure's integrity?

The concept that relies on a natural force to maintain a structure's integrity is grounded in the idea of gravity. Gravity acts on all architectural and structural elements, providing a constant downward force that structures must counteract to remain stable and safe.

When considering structural integrity, it is essential to recognize that buildings and structures must be designed to bear and distribute the gravitational loads they encounter effectively. This means that all materials and forms must be arranged so that they can support their weight, resist bending or buckling, and transfer loads to the ground without failure.

Understanding gravity's role allows architects and engineers to create solutions that prevent collapse or deformation over time, ensuring safety and durability. For instance, the use of materials and forming techniques that counteract gravitational forces is central to architectural design, making this concept foundational in the field.

The other concepts relate to specific forces or techniques employed in construction but do not fundamentally rely on a natural force like gravity does for maintaining structural integrity.