Binding systems are described for applying compressive forces on the refractory hearth and/or refractory sidewall of a circular furnace having an outer metal shell which may be segmented. One preferred binding system comprises a tensioning band having one or more segments which extends around the furnace hearth and/or sidewall, with a resilient connection being provided between the opposite ends of the band and, where the band is segmented, resilient connections are also provided between the ends of adjacent segments. Another preferred binding system comprises a plurality of pivoting members provided around the circumference of the furnace. Each pivoting member is acted upon by a force-generating member which applies a controlled amount of force to the pivoting member and causes it to apply a compressive force to the hearth.