A cable tray includes a plurality of fasteners fastening rungs to side rails. Each fastener may be a radially expandable fastener having a radially expandable portion received in one of the fastener openings of one of the rungs. Each radially expandable portion is in an expanded configuration and frictionally engages the corresponding rung inside the corresponding fastener opening to inhibit withdrawal of the radially expandable fastener from the fastener opening. Each fastener opening may be defined by an interior surface of the corresponding rung and at least one projection extending radially inward from the interior surface relative to the fastener opening. The fastener may have an engagement portion frictionally engaging the corresponding at least one projection inside the corresponding fastener opening to inhibit withdrawal of the radially expandable fastener from the corresponding fastener opening.