A retaining wall that has a strut in compression for soil stability is known as what?

A retaining wall that has a strut in compression for soil stability is best described as a buttress. Buttresses are structural elements that provide support to walls, particularly in situations where lateral pressure from soil needs to be countered. When soil exerts pressure against a retaining wall, a buttress helps stabilize that wall by transferring the load into the ground or the underlying structure more effectively. The design of a buttress typically involves creating a wider base or an additional structural feature that can handle the compressive forces generated by the soil behind the wall.

In contrast, arches are structures designed to carry loads through a curved shape and are not specifically intended for soil stabilization in the same manner as a buttress. Columns and pillars serve to support structures vertically but do not necessarily engage with lateral soil pressure in the way a buttress does. They are primarily designed to transmit loads from the structure above to the ground below rather than specifically to mitigate soil pressures acting against a wall.