Imperial College emeritus professor John Burland played a key role in the launch of GE. Claire Smith spoke to him to talk about the role the magazine has played in the sector over the last 50 years and discussed how the challenges facing the sector have changed.
Since GE’s launch 50 years ago, ground engineering has matured as a science, techniques and equipment used to deliver them have evolved significantly and major advances have been made. Nonetheless, some challenges facing the sector remain unchanged and the ground remains unpredictable which means that there is still much to learn and every site is still unique.
“GE was launched when geotechnics was still an emerging science with big leaps forward being made,” says Imperial College emeritus professor John Burland. Now the changes are smaller, more incremental and there are different challenges but, according to Burland, the fundamentals of geotechnics remain unchanged.
“David Patey and Richard Tilden Smith approached me to talk about the concept of GE when I worked at the Building Research Station with Arthur Penman,” says Burland.
“At that time the only publication for the sector was Géotéchnique – which practitioners found incredibly difficult to read – or the ICE Proceedings, in which there were some good ground engineering papers but there weren’t many.
“They were mostly case histories and projects with no real current comment.
“There was an obvious gap and I felt that practitioners would want something that was relevant to their day to day work and that identified developments without being too formal and going through the rigours of Géotéchnique.”
Technical papers have always been a core part of GE’s offer to the market and Burland says that these helped to establish the magazine.
“GE offered practical application of research and right up to date news items on the latest developments,” explains Burland.
“Other publications still don’t offer the topical viewpoints which GE delivers.
“I still enjoy reading GE very much.”
The late 1960s was a time of major change for the ground engineering sector with new techniques entering the UK market.
“Looking back, the two big developments were large diameter under-reamed piles, which no one really understood – and there were about half a dozen theories that were all in direct conflict with each other – and the other was diaphragm walling,” says Burland.
The first serious bit of diaphragm walling work in the UK was the Hyde Park underpass, soon followed by the basement for Britannic House.
The large diameter piling techniques were brought in from the US and diaphragm walling was brought to the UK by Italy.
“Both techniques opened up the UK industry to greater possibilities and revolutionised the sector,” says Burland.
Source: Richard Tilden Smith
“Previously the market was much more consultant-driven and there was little innovation by contractors.”
Burland sees the introduction of these new techniques as a turning point in this situation with contractors bringing the new techniques from international contractors.
“The next big change brought a move towards ground treatment with compensation grouting and dynamic compaction,” adds Burland.
“This was very much contractor-driven and the industry became more innovative.
“It all centred around control and instrumentation.
“There was a real need for these solutions to enable redevelopment of brownfield sites and use of sites with poorer ground that just couldn’t have been developed without these techniques.”
In the 1970s, it was tunnelling that became important, with the Victoria Line extension. Plans for the Channel Tunnel were also in the offing and tunnelling began to be regarded as very important for the sector, according to Burland.
“At the time tunnelling was a very separate industry from geotechnics, but now the lines between the two are blurred,” he says.
“The demand for tunnelling brought the need for grouting and ground control to the fore.”
Further major developments were driven by contractors and it was from this market that growth in anchoring and soil nailing techniques was driven to meet the needs of the rock and earth cuttings for the expansion of the road network in the 1970s.
“The next development was the use of reinforced earth, which is again a ground treatment,” says Burland.
“The industry was moving from hard engineering solutions to softer solutions.”
In the 1990s there was much more emphasis on limiting building damage. Burland points to the Jubilee Line Extension as an example.
“It was the first time that the impact of tunnels was taken seriously,” he says. “Previously the damage was just repaired.
“The Jubilee Line Extension led to real advances in compensation grouting which benefited the Big Ben clock tower and which was also used at Waterloo on the Victory Arch.
“It brought home the importance of monitoring but there were organisational challenges – some of which still remain – although realtime monitoring has advanced.
Source: Richard Tilden Smith
“The Heathrow collapse was part of this story. Monitoring is still something that we are not very good at and we still need to improve the dissemination of the measurements and the decision-making.
“I learnt a lot about this at Pisa and the need to take ownership and responsibility. Too often responsibility seems to be diffused now.”
Burland references the recent engineering report on the Grenfell fire by Dame Judith Hackett which emphasises the importance of ensuring that there is no ambiguity as to where responsibility lies.
“Dealing with this will be one of the major organisational challenges for the next 50 years,” he says. “We have some super technology available to us but these all need control.”
One of the other major changes is the way design is undertaken.
“In the 1960s there were a lot of hand calculations. I’m torn between the two as there was probably a lot of rule of thumb, but the hand calculation made you think about the problem,” explains Burland.
“Now we have moved to having available huge, off the shelf software packages to undertake calculations and few fully understand the theories and limitations of these packages. There is an over reliance on them.
“Engineers still need to learn the fundamentals so that they can use computer analysis with confidence.”
Burland still feels that the informed use of numerical analysis is one of the major challenges.
“It is so widely used now,” he says.
There is a tendency to throw everything into a software package and out pops an answer that everyone believes.
The Nicoll Highway is a classic example – there are lots of elements to the collapse – but inappropriate analysis and misunderstanding of the instrumentation and monitoring lie at the heart of the problem.
One of Burland’s key messages for engineers delivering the next 50 years of geotechnical innovation is to collaborate and communicate.
“We mustn’t work in silos – the industry must remain collaborative and properly integrated with teams that understand responsibility,” he says.
“The need to look for the right things right from the ground investigation stage has not changed. The ground is still full of surprises and cannot be codified.
“It is now a mature science but there is still much to learn – and long may that last.”