civil engineering Civil engineering is a professional engineering discipline that deals with the design, construction, and maintenance of the physical and naturally built environment, including public works such as roads, bridges, canals, dams, airports, sewa ...

, the middle-third rule states that no tension is developed in a

wall A wall is a structure and a surface that defines an area; carries a load; provides security, shelter, or soundproofing; or, is decorative. There are many kinds of walls, including: * Walls in buildings that form a fundamental part of the su ...

foundation Foundation may refer to: * Foundation (nonprofit), a type of charitable organization ** Foundation (United States law), a type of charitable organization in the U.S. ** Private foundation, a charitable organization that, while serving a good cau ...

if the

resultant force In physics and engineering, a resultant force is the single force and associated torque obtained by combining a system of forces and torques acting on a rigid body In physics, a rigid body (also known as a rigid object) is a solid body in w ...

lies within the middle third of the structure. The rule is covered by various standard texts in the field of civil engineering, for instance ''Principles of Foundation Engineering'' by B.M. Das.Das, B.M. Principles of Foundation Engineering 3rd Ed. PWS Publishing (1995) p.153 The application of this rule is limited to foundations that are square or rectangular in

plan A plan is typically any diagram or list of steps with details of timing and resources, used to achieve an objective to do something. It is commonly understood as a temporal set of intended actions through which one expects to achieve a goal ...

. (For circular foundations a different rule, known as the Middle Quarter Rule applies).

References

Structural engineering {{civil-engineering-stub