Expansion of concrete pavements with small-radii curves can create radial forces large enough to move houses, according to the author, a consulting professional engineer who has seen this phenomenon many times. The situation can occur when summer temperatures expand a curved concrete pavement more than enough to close the contraction joints. The resulting radial force tends to move the pavement and any objects abutting it at the outside of the curve. These objects can be curbs, driveways and even houses at the opposite ends of the driveways. Pictured is a dramatic example of a slab-on-grade house with a very wide diagonal crack through the kitchen floor. The crack was actually created by expansion of the street outside the home, which produced enough force to push the driveway against the garage floor and the garage floor against the slab.
To prevent these problems, the author suggests using wide expansion joints and tie bars across longitudinal joints in streets having curves. The tie bars would keep the joints closed and mobilize more friction between the pavement and subgrade to resist the outward force.
