He was the son of the renowned structural engineer Sir Ralph Freeman, designer of the Sydney Harbour Bridge and founder of Freeman, Fox & Partners. He shared his father's passion for large bridge design and construction - a passion he passed to his son Anthony - and was responsible for the construction of many major projects including the vast Humber suspension bridge - the longest in the world at the time - the Medway Bridge and M2 motorway, the Auckland Harbour Bridge, the Forth Road Bridge, and the Severn and Wye Bridges.
Throughout his long career Freeman dedicated a huge amount of time to the profession through his work for the Institution of Civil Engineers, culminating with his presidency in 1966-67. But his skills also crossed over to the lighter side of engineering, recognised by his knighthood in 1970 while serving as consulting engineer to the Queen, responsible for the upkeep of Sandringham Park, a post he was appointed to in 1949. He was also responsible for managing construction of the South Bank Exhibition, the main showcase for the Festival of Britain in 1951.
Ralph Freeman was born in 1911 and educated at Uppingham School, Leicestershire, and Worcester College, Oxford, where he gained an honours degree in Engineering Science. As a student he worked during the vacations for the steelwork fabricator Dorman Long, both in its Middlesbrough steel works and in London on the construction of Lambeth Bridge and the widening of Putney Bridge across the River Thames.
After graduating, his passion for bridge construction took him to Rhodesia and South Africa with Dorman Long where he spent seven years, from 1932 to 1939, in contracting, building mainly long-span bridges but also the steelworks in Pretoria. It was on one of his long sea trips to Rhodesia that he met Joan Rose from Cape Town. They married in 1939.
His work in Southern Africa included the 320m-span steel Otto Beit suspension bridge across the Zambesi at Chirandu and the 330m steel arch Birchenough Bridge over the Sabi River. Between these two projects he spent six months in Denmark working on the 3.1km steel girder road and rail Storstrom Bridge and then for Braithwaite & Co on an oil pipeline jetty in the Medway. He finally returned to the UK in 1939 to join Freeman, Fox & Partners to work mainly on the design and construction of the Royal Naval Propellant factory in Caerwent, Monmouthshire.
His engineering work did not stop during the war. Freeman served in the Royal Engineers and worked as a Captain in the Experimental Bridging Establishment in Christchurch. There he was involved in the development of a special propped military suspension bridge using Bailey Bridge components - a design later used with great success in Burma.
He was then seconded as chief engineer to 21 Army Group to advise on the construction of Bailey Bridges in France, Belgium, Holland and Germany. In 1945 he was appointed MBE (military) and made Knight of the Orange- Nassau (Netherlands) for his war-time efforts. He continued his military links in civilian life by serving in the Territorial Army Volunteer Reserve and was made commanding officer of the Engineer and Railway Staff Corp in 1969, a post he held for the maximum permitted five-year period.
After the war he rejoined Freeman Fox and was made a partner in 1947. Two years later he was appointed consulting engineer to King George VI to look after Sandringham Park, an honorary position he continued under Queen Elizabeth until he retired in 1976. He oversaw a variety of building alterations including the complete overhaul of the central-heating system - a job which prompted him to describe himself as "the Queen's plumber".
Freeman Fox's growing reputation for structural excellence led to the award in 1949 of a major commission to design and co-ordinate construction of buildings for the South Bank Exhibition as part of the Festival of Britain. This included the spectacular steel-framed and aluminium-clad Dome of Discovery exhibition hall - a structure which commanded almost as much controversy as today's Dome at Greenwich.
After the sudden death of his father in early 1950, Freeman assumed personal responsibility for the project. It was completed to a very tight timescale in time for the Festival opening. He was appointed CBE in 1952 for his contribution to it.
The 1950s were an extremely busy time for the expanding Freeman Fox partnership, based mainly around Freeman's love and knowledge of bridges. The firm also took on major commissions around the world to build thermal and hydro- electric power stations including the Festiniog pumped storage power station in Wales. By 1958 his reputation for large bridge construction led to the invitation to join an international team of engineers to investigate the partial collapse of a huge cantilever highway bridge under construction in Vancouver in Canada.
Freeman took over as senior partner at Freeman Fox in 1963, a position he held until he retired at the age of 68 in 1979. During this time he spearheaded the firm's work on many of the biggest projects in the world at the time. These included the M2 and M5 motorways, the Forth Road Bridge, the Severn Bridge, both Bosphorus Bridges in Turkey and the cross-harbour tunnel and mass transit rail systems in Hong Kong. He was also intimately involved in the aftermath of the catastrophic collapse in 1970 of steel box girder bridges in Milford Haven and across the River Yarra in Melbourne.
His career culminated with the construction of the huge Humber Estuary crossing near Hull. When it finally opened in 1981, two years after Freeman's retirement, it was the longest single-span suspension bridge in the world, 1410m between its two 155m-high pylons. The steel deck design used state- of-the-art streamlining to reduce the wind loading and set new standards for suspension bridge design and construction around the world.
Freeman had become a member of the Institution of Civil Engineers in 1937 and a Fellow in 1946. He was elected a member of Council 1951-56 and again in 1956-61 before becoming President in November 1966. In his presidential address he stressed the need for all branches of engineers to work more closely together and to disseminate information, knowledge and training more effectively through the ranks - themes still discussed at length today. To this end he was a Fellow of the American Society of Civil Engineers from 1948, President of the Welding Institute 1975-77 and an Honorary Fellow of both the Institution of Mechanical Engineers and the Zimbabwe Institution of Engineers.
Throughout his career he wrote many learned papers and received the Telford Premium Prize with his co-author Sir Hubert Shirley-Smith - president a year after Freeman - for a paper on the Birchenough and Otto Beit Bridges in Rhodesia.
His abundant energy and enthusiasm meant he was able to pack a variety of interests into his life around his engineering. As chairman of the Limpsfield Common management committee (1957-82) he successfully chaired an appeal to raise funds and transfer the common to the National Trust in 1972. Like his father, he was the engineering member of the Royal Fine Art Commission and served on the Board of Governors of Westminster Hospital. In 1964 he was made a CVO and two years later he became a member of the Advisory Council for Scientific Research and Development (Army), later the Defence Scientific Advisory Council.
Even after his retirement Sir Ralph Freeman kept an active interest in civil engineering, particularly through the work of his eldest son, Anthony, who tragically died in July as a result of injuries sustained in an accident on the Vasco da Gama bridge in Lisbon in April 1997.
Father and son would talk continuously of their latest adventures in bridge design and construction whenever they met up. In later years they discussed problems and ideas by telephone and Sir Ralph had a fax machine specially installed at home to transmit diagrams and sketches to and from Anthony around the world.
Freeman's other passions included playing golf, sailing yachts and wood and metal work. He was a prolific writer and a regular contributor to the letters pages of the profession's magazine New Civil Engineer, always putting his point forcefully but thoughtfully.
Ralph Freeman, civil engineer: born London 3 February 1911; MBE 1945, CBE 1952; Partner, Freeman, Fox & Partners 1947-79, Senior Partner 1962- 79; Consulting Engineer to the Queen for Sandringham Estate 1949-76; Vice- President, Institution of Civil Engineers 1962-66, President 1966-67; CVO 1964; Kt 1970; married 1939 Joan Rose (one son, one daughter and one son deceased); died Limpsfield, Surrey 24 August 1998.