ITEM 25: TRANSPORTATION GEOTECHNIQUE

The following presents a proposal to form a Subgroup on Transportation Geotechniques, as part of the Soil Mechanics and Foundation Division of the CGS. Transportation Geotechniques refers to the challenges and consequences of building and maintaining infrastructure (rural and urban, road and rail networks, airports) on soil and rock (working definition). The term is not meant to imply a narrow focus on the application of geotechnical principles to a single project or problem, but rather to a broader perspective to include the study of geotechnical issues affecting provincial and national infrastructure networks.

Background

Transportation geotechnique involves numerous broad issues that affect provincial and national policy, with significant financial consequences. Unfortunately, as is all too often the case, the importance of these issues is poorly communicated or not understood by those making the decisions. Some of these issues are:

Many provincial highways authorities have been downsized, out-sourced and privatized. Although these authorities strive to maintain their position as knowledgeable clients, their ability to do so is limited by the outsourcing process, and by general aging of the workforce. Since many agencies no longer do ‘engineering’ work, but rather manage projects, there is little incentive for new graduates to enter this field. These new graduates then work for consultants on specific projects of limited scope. No one is left to tackle the big picture issues and there is no forum available for transportation geotechnique practitioners. Other provinces often repeat efforts and advances put forth by a particular province.

Poorly written Terms of Reference and/or limited geotechnical assessment guidelines are available for consultants to follow for delivery of transportation infrastructure projects. The ‘quality and quantity” of engineering services used to deliver these projects varies from consultant-to-consultant, project-to-project, and time-to-time. The competitive nature of consultant proposals adds to this problem in the sense that low cost is deemed to imply good value.

There is little coordinated effort in research, or even agreement on what the major geotechnical issues are that affect highways. It is noted that the Transportation Association of Canada, TAC, has a mandate to promote safe, efficient, effective and environmentally and financially sustainable transportation services. It provides a forum for exchanging ideas, technical guidelines and best practices. However, TAC does very little work on geotechnical issues. Their Standing Committee on Soils and Materials is focused on pavements and aggregates, and has no specific interest in subgrade materials, slope stability, erosion control, frost heave and the like.

Limited effort is being exerted on pure research into pavement/subgrade interaction, with the exception of Laval and Manitoba. With a nationwide problem of rapidly degenerating infrastructure coupled with limited financial resources, it will be important to advance the case for transportation geotechniques so our tax dollars are spent wisely and are directed toward solving a problem rather that paving over it.

The issue of deferred maintenance costs is coming to the forefront in provincial and national infrastructure decision making. “Deferred Maintenance” is maintenance that was not performed when it should have been or was scheduled to be and which, therefore, is put off or delayed to a future period. Deferred maintenance costs are the capital costs incurred from deferred maintenance. An example might be whether it is better to maintain a roadway over a slowly moving landslide by means of relatively inexpensive yearly patching, or to undertake a more proactive approach and spend significant money to stabilize the site. This kind of question should form a part of any network risk management program but has received very little attention.

The First Ministers signed the Agreement on Internal Trade (1994) to promote an open, efficient, and stable domestic market for long-term job creation, economic growth and stability. It is apparent that there are no national standards for transportation geotechnical work, apart from the guidelines put forth in the CFEM. There is no consistent set of standards for geotechnical work amongst the various provinces. In order to promote inter-provincial engineering services, in support of the AIT, a set of transportation geotechniques best practices should ideally be developed. Best practices are available for pavement design, bridge design and highway geometrics: all of which are founded on geotechnical practices that vary regionally.

Objectives

The objectives of the subgroup are to: Raise the awareness of transportation geotechnique firstly within the geotechnical community and then within the transportation community; Promote a coordinated research effort and dissemination of research findings, with a possible link to TAC since they actually fund research of national interest; Develop a consistent set of best practices to guide practitioners; Provide a forum for practitioners to discuss the broad issues affecting the nation’s infrastructure.

Proposed Subgroup structure

The subgroup would report to the SMFD. A chair would be appointed to lead the group.

Candidate members (not all have been contacted):

Roger Skirrow

Maurius Roy/Guy Dore/Jean Marie Konrad

Tony Ng, Ahmed Shalaby

Chris Bunce/Clive MacKay/Tim Keegan

David Dundas

Initial Programming

Potential members will be contacted within the next month. An initial subgroup meeting would be held via teleconferencing, at which time the group structure would be finalized. A list of long-term and short-term objectives will be developed and specific deliverables will be selected and tasks delegated accordingly. A high priority action item might be to conduct a survey of provincial highway departments to determine and prioritize geotechnical issues. Another priority item might be to sign a MOU with TAC, with the intent of identifying transportation geotechnique research topics of national interest for TAC to fund. Additional support may be sought at an international level through the ISSMGE, Technical Committee TC3 – Geotechnics of Pavements, of which Ahmed Shalaby and Marius Roy are members.

Some related activities have already been established.

The Geotechnical Society of Edmonton will hold a one-day symposium on Transportation Geotechniques, in March of 2004. The symposium will highlight specific transportation infrastructure projects, in addition to broader based discussions of trends and needs.

The 57th CGS conference to be held in Quebec City will hold a workshop on Transportation Geotechniques (Pavements).