St John’s College Cloisters

Szerelmey carried out a complicated package of works to the Grade I listed St John’s College, Canterbury Quadrangle, Oxford. The columns were beginning to fail structurally. Following extensive surveys and ground condition test excavations, immediate works involved installing steel collars to 5 seriously cracked or split colonnade columns and substantial steel temporary props were installed to support the arches above. Szerelmey were engaged to design the temporary works to allow the removal and replacement of the colonnade columns and half columns, and further temporary works to support the frontispieces to allow the removal and replacement of the ground to 1st floor fluted columns. A lengthy process of material sampling was undertaken to find a suitable alternative stone to the original Bletchingdon marble which was no longer available. Swaledale fossil was identified as the preferred replacement, and tested extensively. The new stone columns were installed using a specially designed lifting cradle. Throughout the works extensive periodic movement monitoring was undertaken and during removal of the temporary works and transfer of loads to the new columns continuous monitoring took place. Other works included new stone flooring and entrance steps.