It was the breadth of the human failings that shocked me.  Not the fact that human failings played a part in the collapse – they do often enough when a structure falls down.  What troubled me is that they ran much of the gamut of our darker side, including incompetence and greed, and were exhibited by all parties involved with the mall in it’s 33 year life.

(On the flip side, however, I was impressed by the thoroughness of the judicial investigation.  Also, with the commissioner shooting from the hip and telling it like it is after the findings were in.  Nice that)

If there is a common denominator in the human failings a case could be made for “money” being the one – getting and keeping as much as you can.  Nothing wrong with money except when it blunts your moral and ethical fibre and gets in the way of doing the right thing.

It`s not difficult to believe undue interest in money was there decades ago during the planning of the mall – the developer wanting the most structure for the least money spent.  Then fast forward to a few weeks before the collapse when the engineer signed off on the structure knowing it was unstable – for certain with a view to being retained again and being paid for his services.  And the undue interest in money on the part of the many private and public parties involved in the mall each year over the decades right up to the collapse.

(Be assured: In all my years, I’ve never heard of a professional engineer deliberately falsifying his report.  I’ve been around the block a few times and seen a few things but never this)

We can be excused for wondering how many other structures are on the verge of collapse that we don`t know about – due to similar human failings.  We know about the mall because it fell down.  There are bridges on the east coast that are in poor condition.  But we know about these and the problem is being addressed.  What about the structures that we don`t know about?

I blogged a couple of years ago – shortly after the mall collapsed, about construction inspection and maintenance being the Achilles’ heels of project development, and touched on it again a few weeks ago.  Inadequate construction inspection is almost like a default human failing.  But this singular weakness in project development is not of the breadth and blatancy of the human failings that brought the mall down.

We have our problems in forensic engineering investigation – a development project in a sense to an engineer, where investigations “fail”, that is, they are inadequate because of human failings on the part of owners, counsel, and engineers.  The parties often failing by taking little interest to understand what’s involved in forensic work and that thorough and objective investigations are expensive.

We can’t always prevent the tragic effects of human failings on the built environment any more than we can prevent sick people murdering soldiers and shooting up our parliament.  We must recognize and expect that these tragic events will happen – human nature being what it is, learn from them, and press on.

It helps to focus on the fact that there are few structures in the built environment that are in grossly poor condition and on the verge of collapse.  Fortunately, very, very few, I believe, knowing the engineering profession as I do.  At the same time, however, to recognize that there are some structures in poor condition – but not about to collapse.  Structures that are malfunctioning, performing poorly, and costing money that someone would like to keep and hang onto.

We investigate a considerable variety of accidents and engineering failures.  No two are exactly alike.

Also, our work is ‘small’ and ‘medium’-sized as opposed to ‘big’ and newsworthy.  Not like the collapse of the Elliot Lake Mall in June 2012.  Nor like the landslide in Oso, Washington in March of this year.  We investigate tragedies like these but fortunately infrequently.

The various failures and accidents also stretch across different engineering disciplines.  For example, civil engineering and related specialities like foundation, geotechnical, and environmental engineering, and also structural, electrical, and mechanical engineering.

Similar for civil litigators and insurance personnel? 

I can easily imagine that this variation is not too much different from the mostly no-two-are-alike, small and medium size cases civil litigators handle in Atlantic Canada.  Also those files handled by insurance claims managers, consultants, and adjusters.

(If you are quite busy you can get a quick idea of the variety – just in the forensic civil engineering field alone – by scanning the 16 thumbnail sketches in the list below.  There are links in the References to detailed descriptions of four cases)

I thought to blog on this question when I was recently asked by counsel to briefly describe some of the engineering failures and accidents that I’ve investigated.  I noted 22 individual cases including a couple that were newsworthy.  I was struck by the variety.

Getting an idea of the magnitude of the variation in forensic work

To get some idea of the magnitude of the variation in forensic engineering investigation you might first look at a blog I posted a few weeks ago on the different ways buildings can fail – 34 and counting. (Ref. 1) The author of the book that prompted the earlier blog missed a good number involving the structural and foundation failure of buildings.

Then think about the fact that a building is just one type of structure in the built environment that can have a problem.

Our built environment comprises hundreds of different structures.  For example, bridges, dams, wharves, roads, railways, embankments, transmission towers, power stations, drainage systems, retaining walls, and all the attendant infra structure and mechanical and electrical services.  All have their long list of different ways of failing.

A step ladder is a structure to an engineer.  Also a pile of salt on the road, particularly if it’s a factor in a fatal motor vehicle accident.

Risk of personal injury accidents

It’s not difficult to imagine with such an elaborate and complex built environment that there is also considerable risk for different types of personal injury accidents to occur, as distinct from failures.

For example, there is an extensive literature just on slip, trip and fall accidents alone – many thousands of these types of accidents occur every year in North America, with a number of these in Atlantic Canada.

Questioning a forensic engineer

All this variation might beg the question, “How can any one forensic engineer know how to investigate so many different types of failures and accidents?”  Well, if we stay within our respective disciplines and specialties – civil engineering for me – we can do it.  The basic investigative principles are the same within a specialty regardless the problem.  I suspect the principles are also similar across the different engineering disciplines.  .

What do we investigate in Atlantic Canada? 

The following categories of cases will give you some idea.  The cases are selected from my files.  Each category represents one to several cases.  The Cases are described, in general, and the kinds of Technical issues that might need to be addressed are noted.

No two cases are exactly alike as noted above, and some are very different.  The floor surfaces in the slip and fall accidents are all different.  And slip and fall accidents are very different from a soil-steel bridge failure and also different from toxic fumes in buildings.  And these in turn are different from inadequately underpinned buildings, collapsing retaining walls, landslides, tunnel failures, and vibrating buildings.

Most of the cases were in Atlantic Canada but two were at airports in the Bahamas.  Four cases did not result in litigation but are quite illustrative of the variation in forensic engineering investigation.

1. Floods:  Cases  Frequent land flooding and drainage problems, and flooding of nearby structures.  (In addition, we investigate many basement flooding problems – too numerous to mention)  Technical issues  Generally, determine whether or not construction on adjacent properties caused flooding and an increase in drainage on adjoining properties.  And, in one case, caused a three foot deep flood in the pump room of a recreational facility with a swimming pool.
2. Vibrating buildings:  Cases  The very odd occasional case like a building that vibrates in winter – not in summer, as occupants walk from one end to another.  And ceiling-wall joints open up in winter then close in summer.  Technical issues  Determining the cause of this odd behaviour.  (Difficult to refrain from telling you that it was due to differential frost action on the foundations)  (Ref. 2)
3. Inadequate remediation of fuel oil contaminated sites:  Cases  Suspected inadequate clean-up of contaminated sites at excessive cost.  Technical issues  Confidential interview of 11 clean-up contractors in Atlantic Canada to determine the problems with clean-up operations, the cause of the problems, and the cause and magnitude of cost over-runs. 
4. Collapsing fuel oil tanks:  Cases  Occasional situations are investigated where a structure is undermined by adjacent construction work.  In one case, a domestic fuel oil tank collapsed into an excavation near the foundation of the tank.  Technical issues  Determine the reason why the ground gave way and undermined the tank’s foundations. 
5. Slip, trip and fall accidents resulting in injuries:  Cases  Slip and fall accidents in apartment buildings, recreational facilities, retail outlets, and on sidewalks.  Technical issues   (a) Appropriateness of the floor surfaces – the skid resistance, for the intended usage of the area.  (b) Source of contaminants on floors – a factor in some slip and fall cases.  (c) Maintenance of an area.
6. Accidents resulting in fatalities:  Cases  Accidents resulting in fatalities on highways, dining rooms, and airports.  Technical issues   (a) Whether or not a structure on a highway was a factor causing a vehicle to run off a highway and over a sea cliff.  (b) Whether or not a defect in a ladder caused a worker to fall.  (c) Which wing of an aircraft struck the ground first. (Ref. 3)
7. Bridge collapses:  Cases   Occasional failures involving the collapse of soil-steel bridges – corrugated culverts spanning at least 10 feet in North America, as great as 20 to 25 feet in some locations in Atlantic Canada.  Technical issues   The cause of the collapse.  And in one case, the flood level of the stream the bridge was spanning.
8. Landslides:  Cases  Collapsing slopes – either catastrophic, a slow movement of a mass of material, or the simple sloughing of surface soil, all damaging other structures at the top, on, or at the bottom of the slope.  Technical issues  (a) The cause of the landslide.  (b) Occasionally, design and overseeing stabilization of the slope.
9. Falling objects:  Cases  Objects falling off different structures, e.g., ice from a building injuring a pedestrian below.  Technical issue  Whether or not construction and maintenance of the structure was a factor in causing the object to fall. (Ref. 4)
10. Toxic fumes:  Cases  Occasional toxic odours in buildings requiring closing off of a part of a building or vacating the building completely.  Technical issues  Determining the source and cause of the toxic fumes.
11. Retaining wall collapses:  Cases  Frequent enough collapse or movement of retaining walls located inland or on the coast affecting the wall or property and other structures above or below.  Technical issues  (a) Determining the cause of the collapse, or (b) damage to property and if the damage is related to a failing retaining wall. (Ref. 5)
12. Swimming pool failures:  Cases  Occasional failure of a swimming pool, for example, by movement of the liner.  Technical issues  Determining the reason a liner floated away from the side of the swimming pool.
13. Excessive foundation settlement:  Cases  Frequent enough cases involving settlement of foundations damaging the structure above or affecting its performance.  For example, in one case, rapid, excessive settlement of a swimming pool – many inches in a few months.  And in another case, slow, excessive settlement of a processing plant – many inches in a few years.  Technical issues  (a) Determining the cause of the excessive settlement. (b) Occasionally design remedial work.
14. Inadequately underpinned buildings:  Cases  Frequent enough cases of buildings not being underpinned properly during construction work to fix other problems.  For example, the underpinning of a house associated with remediation of a fuel oil spill.  Also the underpinning of an apartment building during construction of a second multistory apartment building on adjoining property.  Technical issues  (a) In some cases simply determining the adequacy of the underpinning.  (b) In occasional cases, designing and overseeing construction of adequate underpinning.
15. Tunnels:  Cases  Very infrequent case of a tunnel being driven off line.  Technical issues  Determining the cause of the misalignment (In one case I investigated, this was because a very dynamic tunnelling method was completely incompatible with the liquefiable soils the tunnel was being driven through – the saturated soils turned to ‘liquid’ when vibrated)
16. Airport runways:  Cases  A rare case where quite large holes – one to several feet across and deep, were appearing in the surface of a runway.  Technical issues  (a) Determining the cause of the holes – they turned out to be what are called ‘banana’ holes in the Bahamas. (b) Identifying a method to locate potential hole locations. (c) Designing remedial measures.

References

1. How many ways can a building fail? http://www.ericjorden.com/blog/2014/07/10/how-many-ways-can-a-building-fail-and-possibly-result-in-civil-litigation-or-an-insurance-claim/
2. Investigating a vibrating building http://www.ericjorden.com/blog/2013/04/25/investigating- a-vibrating-building/
3. Investigating a fatal MVA http://www.ericjorden.com/blog/2013/03/06/forensic-engineering-investigation-of-a-fatal-mva/
4. Falling roof ice injures man http://www.ericjorden.com/blog/2013/01/18/falling-roof-ice-injures-man/
5. Gabion retaining wall collapse results in litigation http://www.ericjorden.com/blog/2013/02/09/gabion-retaining-wall-collapse-results-in-litigation/