This is particularly the case when\u00a0a failure involves:<\/p>\n
- \n
- the\u00a0terrain at\u00a0the scene of a failure,<\/li>\n
- the foundation soils below,\u00a0and\/or<\/li>\n
- the\u00a0surface water\u00a0and the ground water below the surface.<\/li>\n<\/ul>\n
Problems like this require us to identify:<\/p>\n
- \n
- the different layers of soil and rock beneath a site and<\/li>\n
- the physical properties of the different layers.<\/li>\n
- Also, how the water drains across the terrain’s surface and<\/li>\n
- how the ground water flows beneath the surface.<\/li>\n<\/ul>\n
There’s often pattern\u00a0in these\u00a0elements of a site. \u00a0Based on a review of published topographic, geologic, and hydro-geologic\u00a0mapping, we hypothesize its nature at the start of a forensic engineering or insurance\u00a0investigation.<\/p>\n
But, Mother Nature lies in wait<\/strong>.\u00a0 If there’s one thing I learned as a civil engineer specializing in geotechnical and foundation engineering for a number of years, it\u00a0was to “expect the unexpected” in attempting to characterize the\u00a0foundation soil conditions beneath a site.\u00a0 You can’t see the thing you’re investigating.\u00a0 Also,\u00a0“if in doubt go deeper” with your investigation.\u00a0\u00a0I acquired the former bit of wisdom in the U.K. and the latter in Australia where I practised for a time.<\/p>\n
“Mess” came to mind in connection with this difficulty when I was walking my dog recently\u00a0just as\u00a0a last snow storm was starting – “last” would be nice, but we’re not holding our breath in eastern Canada.<\/p>\n
I was struck by the pattern – quite messy at some locations, in the layers of snow\u00a0plowed up along the sides of the streets.\u00a0 The different layers would\u00a0be different snow storms and we’ve had quite a few.\u00a0\u00a0What I\u00a0saw in the snow was\u00a0illustrative of layers of soil.<\/p>\n
Soil is deposited in layers like snow and can be just as uniform or irregular like that seen in the snow banks.\u00a0 And just as “messy”, irregular, and difficult to describe and characterize, and difficult to cost.<\/p>\n
I took a few pictures and include a selection of these below – Figs 1 to 5 in the Appendix..\u00a0 The pictures are two-dimensional.\u00a0 It’s very important to remember that the irregular, messy pattern continues in the third dimension as well.\u00a0 The layered\u00a0patterns seen in Figs 1\u00a0and 2 are quite uniform.\u00a0 Those\u00a0in Figs 3, 4 and 5 are irregular and messy.<\/p>\n
Similar “messiness” must be expected – as an initial hypothesis, to permeate all forensic work\u00a0where the natural environment is an\u00a0element in the problem.\u00a0 For certain, the environment below the ground surface.\u00a0 But often enough that above as well even though we can see the surface.<\/p>\n
And this “messiness” must be expected\u00a0to confound our efforts to identify all the tasks that will be necessary during a forensic engineering and insurance investigation, the time to carry out these tasks, and their cost.<\/p>\n
Appendix<\/strong><\/p>\n
![\"Fig.](\"http:\/\/www.ericjorden.com\/blog\/wp-content\/uploads\/2015\/04\/IMG_0028-Medium-300x225.jpg\")
<\/a>Fig. 1 Layers of snow at side of road<\/p><\/div>\n
<\/p>\n
<\/p>\n
![\"Fig.](\"http:\/\/www.ericjorden.com\/blog\/wp-content\/uploads\/2015\/04\/IMG_0045-Medium-300x225.jpg\")
<\/a>Fig. 2 Layers of snow at side of road<\/p><\/div>\n
<\/p>\n
![\"Fig.](\"http:\/\/www.ericjorden.com\/blog\/wp-content\/uploads\/2015\/04\/IMG_0031-Medium-300x225.jpg\")
<\/a>Fig. 3 Fairly irregular layers of snow. If this were foundation soil at the site of failure it would be fairly easy to characterize<\/p><\/div>\n
<\/p>\n
![\"Fig.](\"http:\/\/www.ericjorden.com\/blog\/wp-content\/uploads\/2015\/04\/IMG_0010-Medium-300x225.jpg\")
<\/a>Fig. 4 Somewhat more irregular layers of snow. If this were foundation soil it would be more difficult to characterize and would introduce some “messiness” into the forensic engineering investigation<\/p><\/div>\n
<\/p>\n
<\/p>\n
<\/p>\n
![\"Fig.](\"http:\/\/www.ericjorden.com\/blog\/wp-content\/uploads\/2015\/04\/IMG_0021-Medium-300x225.jpg\")
<\/a>Fig. 5 Quite a bit more irregular layers of snow. If this were foundation soil it would be quite difficult to characterize and would introduce a lot of “messiness” into the forensic engineering investigation<\/p><\/div>\n","protected":false},"excerpt":{"rendered":"
Forensic engineering and insurance investigations can sometimes get quite “messy”. We can easily identify the different stages in\u00a0standard investigations – the protocol we must follow to carry out a thorough investigation and to conform to good practice. But we can’t … Continue reading
![\"Fig.](\"http:\/\/www.ericjorden.com\/blog\/wp-content\/uploads\/2015\/04\/IMG_0028-Medium.jpg\")
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