DFI EU Seminar Copenhagen - Program

Jakob Hausgaard Lyngs, President Danish Geotechnical Society & Maurice Bottiau, President DFI Europe

Tony O’Brien, Mott MacDonald

Jonas Ostersen, Aarsleff

Peter Alheid, Hercules
Buckling of piles has been an issue for a long time in Sweden and most of the Nordic countries due to the very loose clays of Scandinavia and Finland, in connection with the historic use of slender piles of both concrete and steel. This has made structural bearing capacity equally important to geotechnical bearing capacity. Since the -70s and the works of Bernander/Svensk analytical calculations of pile buckling in

Jørgen Steenfelt, Cowi
For large scale or important infrastructure projects wind tunnel testing, concrete testing etc. are a given. However, for the most important part, the foundations, testing is routinely dismissed as being too costly or not needed! The only exception is ground anchors where testing is codified. Testing of foundation piles should be mandatory to avoid failures and allow for optimization (cost saving), robustness and ease

Maurice Bottiau, Franki Foundations Belgium & Gilliam de Nijs, BMNED
As the authors have been highlighting in previous papers, many parameters play a role in the final pile performance, from adequate soil investigation to performance monitoring and testing. The correct understanding of pile construction, though, remains crucial. During construction, some unexpected behaviour can occur, and the soil reaction to pile installation can sometimes be completely different than

Håkan Eriksson, GeoMind
Two projects are presented, one that rendered in lots of extra costs and delays and another a success project. The outcome from both projects were strongly dependent on the relationship and interaction between the client and contractor. The on-site development and refinement of the design helped to a great extent to strengthen to confidence between designer, contractor and client.
Soil improvement with dry deep mixing was performed at six peat areas along the A2 Motorway in Poland, near the city of Poznan. The purpose was to reduce settlements and improve stability. In early September 2003, excessive settlement was experienced. Therefore, preliminary investigations of all other peat areas were conducted with the aim to investigate column quality. A conclusion was drawn that the columns were softer than previously experienced based on sampling, sounding and visual inspections. Due to anticipated deterioration and limited time to complete the motorway, it was decided to exchange all installed columns to alternative technical solutions. An expert group, comprising six specialists with different skills, was formed to investigate the reason for the anticipated deterioration of the soil improvement. A constitutive meeting was held in late September 2003. Based on the investigations, it could be concluded that the mixing energy during installation and binder quantities in the gyttja soils were too low to reach the requirements in due time. No deterioration nor microbial processes were affecting the mechanical parameters of the dry deep mixing columns.
A case study is presented on dynamic compaction of rockfill during construction of the new Stockholm Norvik container and ro-ro port. The compaction on land was performed with a 20-tonne pounder using a drop height of 20 metres. Because of the soil type, soundings could not be used to evaluate the compaction effect. The maximum depth of influence therefore measured using inclinometers and was found to be around 10 m, in line with the expected depths. The dynamic response of the rockfill was measured with an accelerometer mounted on the pounder. From the derived versus displacement curves, a displacement modulus was evaluated and incorporated in the superstructure design. The dynamic compaction under water was performed using the same pattern, but due to limited water depths the drop height was 10 m. An attempt to estimate the maximum depth of influence was made by adjusting the well-known Menard empirical relationship between drop height, weight and compaction depth. This was done to take into account the buoyancy effect and water resistance resulting in a lower velocity at impact. Accelerometer measurements of the underwater compaction was also performed to evaluate the dynamic response. As on land, the measurements were used to derive a stress vs displacement curve intended to predict the deformations of the compacted rockfill during construction of the ro-ro quay L-walls. The modulus of the rockfill after compaction was also evaluated by monitoring the craters created during compaction followed by a back calculation of the change of density index. Based on the density index, the modulus could be assessed and compared to the same parameter from accelerometer measurements. Predicted and measured deformations were compared after the construction of the L-walls as well as during placing of additional fill on the harbour area. To shorten to 100-200 words.

Chris Harnan, Ceecom Consult Ltd
The presentation will review a diverse range of projects across 4 continents. An assessment of the driving factors leading to problems on each project will be given. This assessment identifies the common main factors as those relating to design, workmanship, lack of coordination between the parties, inexperienced designer or contractor, unforeseen ground conditions.
Other factors will then be discussed including contractual relationships, who supplies key materials, and how best to minimise risks and optimise opportunities.

Dirk Bennje, Hamburg Port Authority (AöR)
The Port of Hamburg is Germany´s largest seaport. Its main infrastructure consists of approx. 43 km of quay walls for seagoing vessels, more than 140 km of public roads within the port area, 300 km of railway tracks and more than 120 bridges. This infrastructure is maintained by and operated at the responsibility of Hamburg Port Authority (HPA), an institution under public law, which was established in 2005 as part of the merging of various Hamburg authorities with port-related duties. This responsibility puts HPA in the role of an contracting authority that manages a project volume of several hundred million Euros per year. The contracts awarded cover design and construction works of all kind of civil engineering projects within the Port of Hamburg.
In the past, likewise other places in Germany, several of these projects had not been delivered within budget or on schedule. And these projects showed distinct signs of procedures that did not provide value for money. HPA then decided to make a change, and carried out a research to find out the reasons for these grievances. A major reason was found in the traditional contractual relationships, which are usually based on bilateral contracts. Furthermore, the success of a project is greatly influenced by the early integration of all project participants especially contractors, and by implementing a cooperative project delivery which starts as early as in the design phase and continues throughout until the completion of the project. Therefore HPA has started to implement a different contractual model, which is internationally known as Integrated Project Delivery (IPD). Although it is well known internationally it had not been applied in Germany until that point of time. The basic idea of this contractual model is, that the project participants work together with the clients as an integrated team. Decisions are made within the team, solutions are found in cross functional teams and risks are beared together or eliminated. Being the first in Germany HPA has now become a role model for other contracting authorities following its example.

Moderator : Gunilla Franzén, GeoVerkstan

Maurice Bottiau, President DFI Europe & Jakob Hausgaard Lyngs, President Danish Geotechnical Society