Complex sentence: Sir Cyril Kirkpatrick, Chief Engineer for the Port of London and his partners were renowned for expertise in civil engineering projects, one being the construction of the concrete caissons, which formed the Mulberry Harbour to facilitate the D-Day landings.
Split into simpler sentences: Sir Cyril Kirkpatrick, Chief Engineer for the Port of London, established his firm as a leading civil engineering practice. Projects included the construction of the concrete caissons, which formed the Mulberry Harbour to facilitate the D Day landings.