Floating, Leaning and Sliding

Schematic diagrams of the forces acting on the riser box:

All similar structure designs will encounter these forces.   The structures will resist floating, leaning and sliding to some degree through a combination of their weight and soil trapped against the sides and the pipe flange.  These forces can become a significant problem on large and tall boxes.

The Internet has many good references for retaining walls that explain the forces in greater detail.

Our structures have extended bases and provisions for pinning to help support the box and relieve stress on the pipe connection.

We offer optional support frames for tall boxes.   When properly backfilled, these frames will control the floating forces and significantly reduce the tendency for the boxes to lean or slide.    All structures 48 inches and taller can accept support frames and come with appropriate attachment points.   The frames are easily  assembled on site.

Be advised that the soil conditions must be reasonable – backfilling our structure with muck, quicksand or organic material (e.g. wood chips) will not work.

If concerns persist, an inline structure essentially eliminates these design factors.