Early specialist involvement in projects can bring major benefits, says Niall Corney.
The Highways Agency's early contractor involvement (ECI) procurement procedure shows that getting all parties involved at the outset produces a more successful project.
It allows more scope for innovation because there is time to consider new techniques or recent product developments which can bring direct benefits. This suggests consultants should have earlier and more detailed consultation with specialist manufacturers, particularly in the case of geosynthetics.
Professor John Atkinson, in his recent Talking Point (GE May 2006), said: 'Good engineers are innovative. They introduce new theories and methods into their practice; they do not rely on standards codes and precedents.'
I believe this sentiment is at the heart of all successful 'innovative' design in this country. Consultants often feel they must have in-depth specialist knowledge of all aspects of geotechnical engineering and would lose face if they admitted asking advice from material suppliers. This is an outdated perception and can damage a project as the blinkered repetition of old tried and tested design solutions find their way time and again onto design drawings.
A consultant should be akin to a GP, having a broad range of knowledge and a thorough understanding of most ailments, symptoms and the most common treatment methods.
However, GPs know when they need to refer to a specialist.
Engineers can show their awareness of geotechnics, and how fluid its innovative nature is, by overtly bringing expertise from outside organisations to their design process.
This would clearly demonstrate their understanding of the complexities of some of the more fast-moving fields and enable them to put their fingers on the pulse of thinking and practice, allow them to provide true 'value engineering'.
Of course with any specialist sector, be it soil reinforcement, ground improvement or pile design, there comes a point where consultants and contractors have to rely on the expert advice they sought to a level which may be beyond their experience but certainly not their understanding.
For example, the combined design of piles and a basal reinforced platform (BRP) in piled embankments is essential to providing real cost efficiency. In reality the activity is seldom done at the same time either because of a lack of BRP design understanding or a reluctance to specify specific materials capable of producing the most cost-effective pile spacing.
The introduction in recent years of high strength, low strain geosynthetic reinforcement materials such as poly vinyl alcohol (PVA) will lead to a fundamental shift in the design of soil reinforcement elements such as BRPs and reinforced soil slopes.
The issue of strain compatibility between the soil, grid and piles can now therefore be addressed with confidence and a large degree of empirical acceptance. These products can bring enormous benefits to the buildability of a project as well as time and cost savings, but they need to be considered at the earliest possible stage of a project for the full benefit to be realised.
The geosynthetics industry, now about 40 years old, has a wealth of experience and expertise in manufacturers and suppliers of geosynthetic materials.
The soil reinforcement sector, where I work, continues to be one of the most heavily studied.
This is illustrated by the huge range of research projects in progress around the world.
Continual improvements in manufacturing techniques and material processing technology is allowing a whole new range of polymers to be used for soil reinforcement.
I encourage consultants, clients and contractors to engage at the earliest opportunity with those geosynthetics manufacturers who can provide focused, detailed design advice and guidance from their own experienced geotechnical and civil engineers.
Niall Corney is applications engineer at geosynthetic firm Huesker.