Abstract: A plurality of graphite blocks forms a side reflector with an area of each block that allows a certain amount of radiation induced wear in a predefined zone facing the core of the reactor and an area separate from the wear zone for carrying the load bearing function of the side reflector. Most critical is the area of the upper range of the reactor core where radiation induced wear is greatest. The wear is taken into consideration in the design layout of the side reflector in the form of an increment to the thickness of the wall. The load bearing areas of each block provide the load bearing area for the entire side reflector. The side reflector is particularly suitable for high temperature gas-cooled reactors of the pebble bed type.