Monthly Archives: July 2012

The role of a professional engineer assisting counsel prepare a Notice of Claim

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If counsel decides to take a case after meeting with the client and assessing the merits of his or her claim – see post, June 26, 2012, and the dispute has not been resolved by some other means, then civil litigation formally begins with counsel preparing a Notice of Claim.

Preparing and filing a Notice of Claim is one of the first four steps in the civil litigation process collectively known as the Pleadings – several additional steps continue the process to trial:

  • Notice of Claim
  • Statement of Claim
  • Statement of Defense
  • Affidavit of Documents

The Pleadings concisely define the issues between the parties and set out the facts.  The Notice of Claim describes the parties and the fact that the Plaintiff is starting a legal action in court against a defendant or a group of defendants.  The Statements of Claim and Defence, and Counter Claims are a listing of the facts, including the technical facts.

Counsel, in preparing a Notice of Claim, might take a closer look at the existing information relied on initially in deciding whether or not to take the case.

Deciding to prepare a Notice of Claim and go forward with an action is a critical step for counsel and the client.  It’s a critical step because the Plaintiff has gone public in a sense and is on record that they believe they are entitled to damages for a perceived wrong.  To some extent there’s no turning back.  The decision to prepare and file a Notice of Claim must be well informed – see below, Case #1; Damaged Aircraft Wing.

Professional engineers can assist at this stage by also studying the existing information more closely, identifying the known technical issues and facts, and assessing the technical position of the parties that might be involved in the action.  Some new information is likely to be gathered by the engineer (see list below) because of the critical nature of this step.

(Up to this point – preparing a Notice of Claim – an assessment of merit is based mainly on existing information.  Preparing a Statement of Claim to which the Notice of Claim is typically attached is certain to involve some detailed gathering of new information – see future posting).

The role of a professional engineer would involve carrying out the following tasks.  Technical data from these tasks would contribute to counsel’s assessment of the strength of a case and whether or not to actually prepare and file a Notice of Claim and begin a lawsuit:

  1. Visit the site and visually examine exposed surfaces
  2. Confirm Plaintiff’s complaint that the structure has failed or is not performing properly
  3. Study documents and existing information in more detail
  4. Develop initial hypothesis of failure
  5. Refine identification of technical issues
  6. Assess the technical strengths and weaknesses of the case for each party identified by counsel
  7. Brief counsel on where engineering investigations appear to be leading with respect to an opinion on the Plaintiff’s claim and its legitimacy
  8. Outline main engineering investigative tasks
  9. Revise possible investigative costs based on the main tasks, the engineer’s past experience, and engineering precedents

Case #1; Damaged Aircraft Wing: Assessing technical strength.  A lawyer considered that his client had a claim for more than one million dollars in damages to an aircraft wing.  The lawyer was quite certain about this.  It was understood that hydrochloric acid had formed in an exhaust pipe from a paint shop and dripped on the wing corroding the skin and the spar inside.  A professional engineer was retained to investigate the situation.  He established during a visual examination of the site that the aircraft wing was damaged by acid but the situation was such that the client did not have a strong case.  Preparation of the Notice of Claim was stopped.    

References

  1. Stockwood, Q.C., David, Civil Litigation, A Practical Handbook, 5th edition, Thompson Carswell, 2004
  2. Walker, Janet, General Ed., The Civil Litigation Process: Cases and Materials, 6th edition, Emond Montgomery Publications, 2005
  3. The Civil Litigation Process – An Overview, Heydary Samuel, Ontario
  4. Going to Court: Civil Trial Procedure, Community Legal Information Association of P.E.I., Inc. November 2003
  5. Flow charts summarizing the process of civil litigation under the Rules of Civil Procedure, Ontario, January 1, 2010

 

 

Landslide!

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Landslides are frightening and an example of one more way nature has her way with us when conditions are right.  Such a large mass of soil and rock sweeping away everything in its path must be terrifying to see, and terrifying to be in.  I’ve seen the aftermath of large landslides and earthwork failures and investigated some.  They are a humbling experience.

The recent landslides in B.C. at Fairmont Hot Springs Resort and Johnsons Landing on Kootenay Lake certainly fall in that frightening category.  Others in B.C. and elsewhere in Canada, including the Atlantic provinces, are smaller but still serious in causing injury and financial loss.

News reports indicated that geotechnical engineers and geological speciallsts were on the disaster sites within hours of the landslide.  A good thing quickly getting knowledgeable technical people there.  Landslides are engineering failures, particularly when they affect people  The investigations they do and the data they collect are certain to assume the status of forensic engineering investigations.

(Geotechnical engineers are civil engineers who have specialised in the investigation and study of the physical properties of soil and rock as engineering materials)

These large landslides appear to have occurred after smaller landslides along streams – like Fairmont Creek, created dams causing water levels to rise.  Eventually the rising water would overtop the dam and wash it away and downstream.  The mixture of stream water and dam material would pick up other material along the stream bed to create the mass of soil that swept over the inhabited areas as a large landslide.

It’s certain more landslides are occurring in B.C. as I write, both large and small.  If not in or near inhabited areas then in remote areas for sure.

Landslides are natural geological events.  They occur when conditions are right – the strength of the soil on a sliding surface is not great enough to hold back the mass of soil.

The physics principle involved is the same as that underlying the reason we slip on ice in winter and fall and are able to ski on snow and have fun.

Sometimes the strength of the soil is just great enough that the mass of soil stays in place.  Until something comes along to reduce the strength that little bit so it’s no longer adequate.  Or increase the weight of the mass of soil.  That something can be water – rainwater.  The water is said to “trigger” the landslide, a term used by geotechnical engineers and sometimes the general public.

Once the mass of soil starts to move – the land starts to slide, it takes the easiest path like flowing water.  Simply downhill – down a slope, or down a natural channel in the terrain, for example, a water course or stream bed.  The mass of soil in a landslide can be quite “liquid”.

Geotechnical engineers can investigate, analyse, and predict with considerable accuracy that a landslide will occur.  They cannot really say when.  Except perhaps when it’s imminent if they are able to examine the terrain for the signs.  For example, signs like fissures in the ground surface – “tension” cracks to engineers, leaning trees, and muddy water like that seen at Fairmont Hot Springs Resort.

They can also advise with some confidence on the stability of a sliding mass of soil that has come to rest like the geotechnicians did at the Resort.  Their degree of confidence would likely be greater than that possible by structural engineers at the site of a collapsed building like the one at Elliot Lake.

Engineering Investigation

A geotechnical engineering investigation of a landslide – either before the event to predict the likelihood of its occurrence or afterwards to determine the cause – would have the fundamental components of an engineering failure investigation:

  • Gathering data
  • Analysing data
  • Developing an opinion

Data would be gathered in two basic stages:

  • Gather together existing data
  • Gather new data

These basic stages are likely underway at present at the Fairmont Hot Springs Resort and Johnsons Landing.

Existing data is often concerned with conditions at the ground surface and new data with conditions below the surface.

Existing Data

Existing data might consist of:

  • Air photos
  • Infrared photography
  • Topographic maps
  • Geologic maps, particularly soil maps if the sliding mass is in soil
  • Published soil physical properties
  • Hydrogeologic maps
  • Forest cover; vegetation in general
  • Local weather and climate
  • Walk-over surveys (several times during a study of the existing data)
  • Local history and knowledge of past landslides

Reviewing and studying existing data like this, an experienced geotechnical engineer could offer a quite informed and fairly confident statement on the susceptibility of an existing hillside to landslides, or the cause of an existing landslide.

Statements like these have likely already been made about the landslides in British Columbia.

New Data

New data that would increase the confidence of the geotechnical engineer in his opinions would consist of:

  • Surveying (topographic) the site to determine the size and dimensions of the landslide
  • Estimating the volume of soil and rock that slid
  • Augering and drilling boreholes to do field tests and get soil and rock samples for laboratory tests
  • Determining the depth of the sliding surface
  • Constructing groundwater monitoring wells to determine the depth to the watertable and the flow of the groundwater
  • Installing instrumentation to monitor slope movement

Analysis

Investigative tasks like the above provide a lot of data to be analysed.  But the results of the analysis enable well-founded opinions to be formed on the cause of the landslide and remedial work to begin.  The analysis also enables areas prone to landslides to be avoided when building new structures or to be stabilized before building.

Cause of the roof collapse at Elliot Lake

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A good initial hypothesis would quickly dismiss inadequate structural engineering design as the cause of the roof collapse.  The structure is likely to be simple in the extreme: Structural concrete slabs supported by regularly spaced columns bearing on concrete footings on good foundation soil.

If design had been inadequate the mall might have collapsed long ago.  The “loads” (see below) in a simple building are easy for structural engineers to calculate and provide for.

Professional engineers are not infallible but we are governed by professional bodies that do watch us closely.  We carry out our designs according to well understood principles and are held to a strict code of ethics.  Cost is a factor in design; designs must be economical, but not at the expense of safety.

It’s sometimes another matter, however, once the construction drawings leave the design office.  Design can be all well and good but construction inspection is sometimes left wanting.

The pressure on design engineers – not much really, is applying fairly simple design principles in providing for support of the structure, for a reasonable fee.  The pressure on builders – quite a lot of pressue, actually, is getting the structure erected as quickly as possible, for the lowest price.  The pressure on the inspector is ensuring the design is implemented properly, sometimes for a reasonable fee and sometimes with experienced, full time inspection, but not always.  Construction inspection sometimes gets the short end of the stick as far as being adequately funded and staffed.

Inadequate inspection and/or faulty construction would be a good second hypothesis as the cause of the failure.

Inadequate maintenance could be a third, particularly if coupled with inadequate construction.  For example, inadequate drainage of corrosive water and exposed, inadequately covered structural steel.

There are many factors that could bring a building down: Corrosion – mentioned above, weather, various aging effects inherent in the choice of materials, original design mistakes – as acknowledged above but unlikely in simple structures, abuse, unexpected loads and external forces.

These items or factors can be divided into two fundamental categories:

  • Static load support deficiences, and
  • Dynamic load deficiences.

Static loads – weight in laymen’s terms, are the basic weight of the building itself and its contents.  A building has to be strong enough to resist gravity and hold itself up.  The static loads can be subdivided into two categories:

  • Dead loads, and
  • Live loads.

Dead loads are loads that never seem to change in a building such as the weight of the floors, walls and roof.  Live loads are loads that can sometimes change in a building due to weather, occupancy, or building use.  For example, the people, furniture and equipment, and possibly vehicles in a parking garage (see below), etc.

Dynamic loads are loads on a building that change during a relatively short period of time.  They are repeatedly applied and released.  Dynamic loads are added to the static loads.  Typical dynamic loads include strong and variable winds, machinery that pounds or shakes the floors of a building (vehicles in a parking garage?), and earthquakes.  Dynamic loads can sometimes cause contruction materials to fail due to fatique.

Any one or more of several factors could have brought the building in Elliot Lake down.  For sure, inadequate design of a simple building is a possibility but, based on my experience, inadequate construction and maintenace are more likely causes, and good second hypotheses.

I propose, but who knows until a thorough forensic engineering investigation is carried out?

Reference

James, Stuart H. and Nordby, Jon J., Editors, Forensic Science; An Introduction to Scientific and Investigative Technicques, 2nd ed., Chap. 23, Taylor & Francis 2005

Unsafe roof debris at Elliot Lake an easy call for a professional engineer

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Removing a pile of debris is like the game of pick-up-sticks where you lose if a stick moves.  Only with roof debris your “loss” might be an injury possibly a serious one to yourself or the survivors you’re seeking.

Professional engineers know about supporting and holding things up properly.  That’s what structural engineering is all about.  Having a forensic structural engineer on the first response team would seem to be a good idea.  They are going to be involved in any event determining the cause of the collapse.

Good response leadership – which was lacking at the Elliot Lake roof collapse according to an editorial in Saturday’s Globe and Mail, needs good advice.  What better place to get it than from people who design things to stand up?

Swift action involving engineers is also needed because so much of the evidence associated with a collapse is of a perishable nature – some of it highly perishable.  Steel and concrete fracture surfaces will corrode and weather, debris will be moved and memories will fade.

The first steps in the forensic structural engineering investigation of a collapse are critical and concerned with safety in the debris, the “pile of sticks” that the debris is not at all unlike.  They may also profoundly influence the success of subsequent forensic technical investigations.

The engineer may be requested to assess the safety and stability of a structure for a variety of possible reasons:

  1. To assist in identifying the safest routes through the debris, or identifying areas that must be avoided until stabilized
  2. To assist in identifying components that are in imminent danger of further collapse.
  3. To evaluate methods of stabilizing the structure.
  4. To assist in determining whether it is advisable to provide protection for the public.
  5. To assist in evaluating alternative demolition or dismantling sequences.

An argument could even be made for having the first response team to a collapse site headed up and directed by a professional engineer with a project management background.

References

The Globe and Mail, Saturday, June 30, 2012, page F8 Comment.

Ratay, Robert T., Forensic Structural Engineering Handbook, Chap. 4, The First Steps After a Failure, McGraw Hill, 2000