Specialised solutions: Evolving techniques in the foundations industry.
By Becca Wilkins08 October 2009
Foundations equipment manufacturers are focusing on developing more environmentally friendly and specialised piling techniques to meet different market needs. Improving operator comfort as well as complying with engine emissions regulations remain priorities. Becca Wilkins reports.
Among the many challenges the foundations equipment sector must face, improving machine productivity is key and one way this can be achieved is by enhancing the operator's working environment.
Speaking for Bauer, Christian Gress said while productivity and operator safety are key issues in the foundations industry, complying with the Stage IIIB/Tier 4 interim emissions regulations is currently one of the most vital and time consuming projects.
According to Mr Gress the main challenge is to enlarge the machine's engine compartment in order to accommodate the new engine and associated parts.
"It's had a major impact on the design of the whole upper carriage structure," he said.
"If you want to incorporate the engine and other components in a nice and professional manner it more or less means a redesign of all the upper structures or the rotating bases that we are using on our machines."
Techniques and technology
Meanwhile, construction projects are taking place in increasingly challenging environments and so developing and refining technologies used in foundations techniques is another area of focus.
A growing trend towards reducing noise and emissions levels has meant drilling technologies such as, kelly, double rotary and continuous flight auger drilling, have become more popular - rather using a typical piling method, such as a hammer or vibrator, according to Liebherr's Wolfgang Pfister.
He added, in particular double rotary head drilling, which combines uncased auger drilling with cased drilling, has proven to be a very efficient technique.
Mr Pfister explained this process can be carried out in virtually any soil, it is also quick, efficient and accurate due to the opposed rotation of the drilling tools and emits low noise levels.
Bauer, meanwhile, continues to focus on the displacement piling method and the cutter soil mixing method. However, Mr Gress said, "Double rotary drilling is becoming more of a focus and interestingly so is very large diameter drilling, from 2,5 m to 3 m diameters and sometimes more.
"This is because in some areas there are different requirements, possibly due to earthquake risks and also there are some projects where it is easier to drill one big pile rather than 12 small piles and then group them altogether in a pile group."
Manufacturers agree that the geographical location of a piling project will usually determine the type of foundation technique being used.
Mr Pfister said, "The more we move towards the north including northern Germany and Scandinavia, the higher the acceptance of typical pile driving applications - such as pile driving with hammers or vibrators. One reason for this is the specific soil condition that allows the driving of piles. Whereas in Italy, for example, drilling applications are preferred."
Mr Gress agrees that specific countries prefer specific techniques. "Some countries are very innovative they go for new technologies. However, some countries are a bit more conservative."
He said double rotary head drilling with the torque multiplier is successful in the UK, whereas there is a trend for displacement piling and cutter soil mixing in Italy.
Tightening of European regulations and increasing environmental awareness has encouraged foundations equipment manufacturers to prioritise safety and comfort features in their latest models. Electronic controls can enhance the operator's working environment further still and play an increasingly important part in machine design.
Liebherr's safety features include a rear view camera in its drill rig range, handrails or foldable access ladders and the new spoil control system that prevents that the excavated material causing damage to operators and equipment. Another safety feature is the company's CanBus Litronic control device.
"All information, warnings and failure indications required for machine operation are clearly displayed on the monitor in the operator's cab and also stored in the system. This allows optimum diagnosis and early detection and prevention of more serious defects," Mr Pfister said.
Meanwhile, Bauer's B-Tronic system features software for recording data as well as for aiding the drilling process. This, according to Mr Gress, makes life easier for the operator because the system provides him with warnings relating to specific machine functions.
"The B-Tronic shows the operator all the data online, such as the loads that he has on the winches or the mast inclination as well as showing him his position. These things are limited electronically - for example, the mast is prevented from being moved too far so the rig doesn't tip over. However, of course there are still some things in the operator's hands," Mr Gress said.
The B-Tronic system allows for specialised drilling methods such as displacement or continuous flight auger (CFA) piling to be carried out. The system also has a "drilling resistance" device which controls drilling and RPM speeds.
Mr Gress explained, "This always gives optimum performance in penetrating the soil and optimum speed for creating a high quality foundation element. I would say this is one of the key things that we have incorporated in the rigs."
Manufacturers are focused on tailor-making foundations techniques for specific markets and applications. Some are also diversifying into other markets in order to be best positioned for when stability in the construction market returns.
There are several trends that will continue to drive the industry forwards according to Mr Pfister. Increasing awareness of high oil prices means that fuel consumption will remain a key area of focus and being able to easily transport and assemble foundation rigs is becoming more important in new product design, he said.
Meanwhile, energy related and infrastructure projects will remain crucial to the future of the sector, Mr Gress said, adding that Bauer is looking to increase its presence in the off-shore market.
"The opportunities that we see are in those very specialised and complicated projects," he stated.