ACPA 2017 Pipe School Arlington Texas Engineering Responsibility

ACPA 2017 Pipe School – Arlington, Texas Engineering Responsibility The Engineer’s Duty of Care… The importance of understanding (and learning from) failure… www. concrete-pipe. org

2 They told me is was a …. Discernment • “acuteness of judgment and understanding. ” • Synonyms… § judgment, perspicacity, penetration, insight • “keenness of mental perception and understanding” www. concrete-pipe. org

3 The Engineer’s Duty of Care The importance of understanding failure… What are the ramifications of what we do? Chris Macey Americas Technical Practice Leader Condition Assessment & Rehabilitation of Pipelines www. concrete-pipe. org

The Engineer’s Duty of Care § § www. concrete-pipe. org The concept of an Engineer’s Duty of Care has its roots in: § Jurisprudence (the law) § The response of Engineers to failure Not a new concept § In North America, dates back to the earliest part of the last century § All of original discussions with respect to duty of care relate to some pretty famous failures 4

Some things just don’t work out the way we’d like… • Quebec Bridge collapse (1907), Theodore Cooper • Boston molasses disaster (1919) • Chevrolet Corvair safety problems (1960 s), Ralph Nader, and Unsafe at Any Speed • Ford Pinto safety problems (1970 s) • Citigroup Center (1978), • Three Mile Island accident (1979) • Love Canal (1980) • Kansas City Hyatt Regency walkway collapse (1981) • Bhopal disaster (1984) • Chernobyl disaster (1986) • Space Shuttle Challenger disaster (1986) • Space Shuttle Columbia disaster (2003) www. concrete-pipe. org 5

Who thought up this crazy idea of duty, anyway? • When the 19 th century drew to a close and the 20 th century began, there had been series of significant structural failures, – Ashtabula River Railroad Disaster (1876), – Tay Bridge Disaster (1879), and – Johnstown Flood (1889) – the Quebec Bridge collapse (1907). www. concrete-pipe. org • These had a profound effect on engineers and forced the profession to confront shortcomings in technical and construction practice, as well as ethical standards. 6

The popular consensus is that as Engineers, we owe a high duty of care to protect the safety and welfare of the public 7 • Institute of Electrical and Electronics Engineers: "We, the members of the IEEE, … do hereby commit ourselves to the highest ethical and professional conduct and agree: 1. to accept responsibility in making decisions consistent with the safety, health and welfare of the public, and to disclose promptly factors that might endanger the public or the environment; ” • Institution of Civil Engineers: "Members of the ICE should always be aware of their overriding responsibility to the public good. A member’s obligations to the client can never override this, and members of the ICE should not enter undertakings which compromise this responsibility. The ‘public good’ encompasses care and respect for the environment, and for humanity’s cultural, historical and archaeological heritage, as well as the primary responsibility members have to protect the health and well being of present and future generations. ” www. concrete-pipe. org

And more… • Professional Engineers Ontario: "A practitioner shall regard the practitioner's duty to public welfare as paramount. ” • National Society of Professional Engineers: "Engineers, in the fulfillment of their professional duties, shall: Hold paramount the safety, health, and welfare of the public. ” • American Society of Mechanical Engineers: "Engineers shall hold paramount the safety, health and welfare of the public in the performance of their professional duties. ” www. concrete-pipe. org 8

9 You won’t find a group of Engineers on earth who don’t purport to have the safety and welfare of the public at heart • Institute of Industrial Engineers: "Engineers uphold and advance the integrity, honor and dignity of the engineering profession by: 2. Being honest and impartial, and serving with fidelity the public, their employers and clients. “ • American Institute of Chemical Engineers: "To achieve these goals, members shall hold paramount the safety, health and welfare of the public and protect the environment in performance of their professional duties. “ • American Nuclear Society: "ANS members uphold and advance the integrity and honor of their professions by using their knowledge and skill for the enhancement of human welfare and the environment; being honest and impartial; serving with fidelity the public, their employers, and their clients; and striving to continuously improve the competence and prestige of their various professions. " www. concrete-pipe. org

And yet disaster is still with us… www. concrete-pipe. org 10

Quebec Bridge (1907) 11 • 987 m (3240 feet) long, 29 m (95 feet) wide, and 104 m (341 feet) high. • Cantilever arms 177 m (580 feet) long support a 195 m (640 feet) central structure, for a total span of 549 m (1801 feet) • Still the longest cantilever bridge span in the world • Its span was increased in transition from preliminary design to construction phase • Its design was never really, re-visited in the construction phase www. concrete-pipe. org

Quebec Bridge (1907) 12 • The actual weight of the bridge was far in excess of its carrying capacity • The severity of the design issues were well understood and discussed during construction from 1904 thru 1907 Of the 86 workers on the bridge that day, 75 were killed and the rest were injured, making it the world's worst bridge construction disaster. www. concrete-pipe. org • Engineer in charge of construction increased “theoretical” strength of steel instead of re-visiting design • South arm and part of the central section of the bridge collapsed into the St. Lawrence River in just 15 seconds on August 29, 1907.

Quebec Bridge (1916) 13 • If that wasn’t bad enough… • On September 11, 1916, when the central span was being raised into position in its reconstruction, it fell into the river, killing 13 workers (lifting plan wasn’t’ well thought out) • That span still lies at the bottom of the St. Lawrence River www. concrete-pipe. org

Quebec Bridge Collapse of 1907 is largely credited with the evolution of the Engineer’s modern duty of care - raised serious ethical issues about an engineer’s duty to inform • ASCE articulate these as well as anyone: 1. Engineers shall hold paramount the safety, health and welfare of the public and shall strive to comply with the principles of sustainable development in the performance of their professional duties. 2. Engineers shall perform services only in areas of their competence. 3. Engineers shall issue public statements only in an objective and truthful manner. www. concrete-pipe. org 14

ASCE defined duty of care 15 4. Engineers shall act in professional matters for each employer or client as faithful agents or trustees, and shall avoid conflicts of interest. 5. Engineers shall build their professional reputation on the merit of their services and shall not compete unfairly with others. 6. Engineers shall act in such a manner as to uphold and enhance the honor, integrity, and dignity of the engineering profession and shall act with zero-tolerance for bribery, fraud, and corruption. 7. Engineers shall continue their professional development throughout their careers, and shall provide opportunities for the professional development of those engineers under their supervision. www. concrete-pipe. org

And still we have disasters… Hyatt-Regency (1981) – Friday July 17, 1981: Two connected walkways collapsed and plunged into the lobby holding a tea dance, killing 114 people and injuring 216 others – Worst building disaster on planet other than the World Trade Centre – Unlike the WTC, a completely preventable disaster – It highlights some interesting concepts • The designer’s duty to the Contractor to design something that can realistically be built • Making people fully aware of the design concept 16

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From design to construction phase… 18 • Do we have a professional duty to design something that is constructible? • How do communicate design intent? • Do we have a duty to put reasonable provisions in place that we design is what was built? • In Canadian jurisprudence the answers to both of these questions is yes • In the U. S. maybe a little foggy but not a lot foggy…

But what about pipe disasters? ? • Pipe failures are a unique class of failure – Out of sight, out of mind • More commonly occurring long after someone screwed up • Sometimes the screw up is just forgetting about the pipe • But almost every critical pipe failure is a preventable event – Both in pressure and gravity service 19

Gravity pipe failures, traditionally fail over a longer period of time 20

The process usually has three stages… • Some points to note: – Initial defects usually relate to design and/or construction deficiencies – Some short term (structural or hydrostatic integrity), some long term (material degradation) – Deterioration rate relates to the nature of the defects that occur and involves loss of ground – Collapse of the weakened structure may or may not proceed a more spectacular failure due to the loss of ground – A SINKHOLE 21

Highway 174: Ottawa, ON 22

My home town 23

Let me do some math for you… www. concrete-pipe. org 24

Simple Math from my home town… • Winnipeg reached about 250, 000 in population before 1920 • A large chunk of the inventory is/was very old • Did some quick math • We were fixing each pipe once every 1, 869 years!!!! 25

Fabric decay or pipe/soil interaction? This is way scarier than this 26

Meridian, Mississippi; Culvert Failure 2015 – They’re not all sinkholes www. concrete-pipe. org 27

Long Term Duty 28 • We have a duty to report to the public on the condition of their infrastructure and the risk it poses to them – To use the technology and knowledge we have of material behavior to quantify condition – To use our understanding of failure modes and articulate to them the risk that critical components of their infrastructure poses to them • We need to come clean about the systems we inherited and the need to put better systems in place to preclude this happening in the future • We need to practice sound, risk-based engineering with our infrastructure systems

The Short Term Duty is big deal too! • Most of the pipe defects we allow clients to bring into inventory are completely preventable • Most, not all, because the economics of being perfect doesn’t work all the time • We can keep most defects out of inventory very cost effectively and use risk-based logic to be perfect where you need to be • In assessing our short term duty, let’s start with assessing the designer’s duty to various parties and set some simple rules up • Let’s make sure design is actually done 29

A Designer’s Duty 30 1. Perform a design function – – – Learn from past designs don’t c-job stuff you don’t understand Secure some real information about sub-surface conditions Actually do some calculations 2. Think about your duty to the Contractor – – Recognize reasonable means, methods, and techniques of construction Highlight areas that require extraordinary effort Minimize the caliber of gun you give him to cause his own demise Articulate your design concept clearly 3. Put reasonable Qa controls in place so that things don’t get screwed up – Or to make what does, a manageable fix 4. Put meaningful acceptance testing in place to confirm that the design intent was achieved

A couple of case studies to illustrate the point… • We’ll start with the bad…. • A western Canadian City with an un-named consultant (they have all performed equally as bad at times, even some of my own ) • In response to a concrete pipe that settled in poor soils with no foundation constructed, a designer decides to install DR 41 PVC in adverse soils… 31

Independent Design Review • A 1200 mm (48”) Sanitary Trunk, about 2. 25 km (1. 4 mi) long through some very challenging soil and groundwater conditions • City identified a number of design concerns that they requested some comment on. This included: – Buoyancy – Extent of adverse soils – Structural adequacy of DR 41 PVC – Foundation construction and means to quantify adverse foundation conditions 32

33 What are soft soils? AWWA M 45

Dissemination of route where soil strength testing was carried out • More disturbing • Geotech was hired based on lowest cost • Where detailed testing was matched against visual classification – no correlation • Lack of understanding just increased another 33% to 55% of route! 34

35 • What the geotech says in words shhould reasonably match what they measure in real tests • Otherwise, what you see in words, doesn’t have a lot of meaning www. concrete-pipe. org

36 Structural Design of a solid wall PVC Pipe • Structural design review (mine, designer never performed one), concluded – If deflection controlled, no other structural limit state concerns • DR 41 is a “very” flexible pipe (PS < 260 k. Pa – 37 psi) – In 1200 mm (48”) diameter DR 41 was max solid wall thickness available in PVC at the time • Very flexible pipe are outside the realm of current deflection model used for design

37 ~85% SPD

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39 ~85% SPD 90 -95% SPD

So it was simple but a tall order… • Get 95% SPD in the embedment zone – 95% is tall order, can certainly be done but requires Contractor to go in with his head up and right embedment material – “washed” stone, needs to be isolated from most soft materials • If open graded, will likely need to run a compaction trial to quantify embedment compaction protocol as a densometer won’t work • Will need geotextile to preclude migration – Need to consider impact of soft native soils 40

What does trench look like in soft soils? It can get very wide! www. concrete-pipe. org 41

How soft were these soils? They needed a foundation 42

Design Review Spec Summary 43 • The saddest part of this review was what was in the proposed Contract • 186 page spec • 185 pages of nothing about the pipe or its installation (legalese) • 1 liner on last page with the phrase – “Build according to City … Standard Spec” – Sadly, City had no spec for DR 41 PVC pipe at time and indicated that spec, in general was not applicable to work in adverse soils

Result – and this is probably the good news… 44 Engineer’s Estimate (bit of an oxymoron in this case) • $8. 9 million (not really re-adjusted for tendered risk) • 2 bids • $23. 9 million • $35 million • Big proviso was that $23. 9 million bid refused to bid job as designed (neither material nor construction method) • Would build MTBM with an alternate material and no design provided • Owner accepted alternate bid www. concrete-pipe. org

Case history #2 • Circle Drive Project in Saskatoon… • $245 million design build • Some deep, large diameter concrete pipe installed in open trench conditions 45

Reinforced Concrete Pipe Design under Extreme Loading Conditions using ASCE Standard Practice 15 -98 and Beyond… 46 • What’s extreme? Finished grade – Big pipe = 3 m diameter (10 foot) – Contractor says its open cut – Manufacturer says we only have a B-wall to work with – Cover > 16 m (52 feet)

Reinforced Concrete Pipe Design under Extreme Loading Conditions using ASCE Standard Practice 15 -98 and Beyond… • What’s extreme? – Big pipe = 2. 7 m diameter (9 foot) – Contractor says it is still open cut – Manufacturer says I can have a C-wall to work with (10. 75 inches) – But cover increases 21 m (~ 70 feet) Finished grade way out of photo!!! 47

What’s extreme? 48 • When you have to put so much steel in the pipe, you wonder whether the concrete will fit or not?

Heger or Marston Loads, didn’t matter, they were big numbers Equivalent Maximum Upstream MH Downstream MH Cover 10 -65 Outfall ft 27. 01 10 -64 10 -63 10 -62 10 -61 10 -60 10 -65 10 -64 10 -63 10 -62 10 -61 31. 00 31. 71 25. 21 37. 59 10 -60 43. 96 10 -40 10 -59 51. 73 10 -58 10 -40 68. 90 Design Cover Soil Load ID t ft 31. 71 37. 59 43. 96 51. 73 68. 90 kip/LF 63. 22 65. 56 63. 22 74. 49 77. 25 86. 70 89. 91 101. 59 105. 36 122. 47 in 120. 00 120. 00 108. 00 in 11. 00 11. 00 10. 75 49

Why Direct Design? • Large pipe and loads in excess of 105, 000 lb/LF in the 10 foot pipe and over 122, 000 lb/LF in the 9 foot • Need rigorous design approach to check all failure modes – Service crack control, – Flexure, – Diagonal tension, and – Radial tension • ASCE 15 -98 (or as practiced in current AASHTO spec, ASTM C 1417 and C 1479) 50

Soil structure requirements – Consider Constructability Upstream MH Downstream MH Installation Type Design Cover Soil Load ID 10 -65 Outfall 10 -64 10 -63 10 -62 10 -61 10 -60 10 -65 10 -64 10 -63 10 -62 10 -61 10 -59 10 -60 10 -40 10 -59 10 -58 10 -40 1 2 1 1 1 2 1 2 1 ft 31. 71 37. 59 43. 96 51. 73 68. 90 kip/LF 63. 22 65. 56 63. 22 74. 49 77. 25 86. 70 89. 91 101. 59 105. 36 122. 47 in 120. 00 120. 00 108. 00 51 • We were trying to give the Contractor Type 2 installs for ease of construction (90% SPD) • At higher loadings we couldn’t get enough steel in a B-wall to make the design work ~ move to Type 1 installations – 95% SPD

Soil structure requirements – Consider Constructability 52 Haunch material -Readily compactable -Coarse aggregate Middle third -True bedding sand -A loosely placed “ “burrito”

Grade, “loose” material in middle third, stiff material in haunch area is not easy…meet the “burrito” 53

54 For some context went back to to source for ideas…Heger 1988”

And that is exactly what the Contractor did… 55

Load Tests • ASCE 15 -98 acceptance – Constituent material properties – Verification of steel placement – Verification of dimensional control • No Proof of Design test, analogous to ASTM C 76 that tests the finished product – Owner (and designer) was very uncomfortable with this • So we added one! 56

Load Tests 57 • Ran Load Tests to Verify the Design – Allowed verification of assembled product properties in 3 -edge bearing – Served to confirm pull out capacity of stirrups – Check on overall stirrup performance at shear control – Demonstrated service crack width control at loads much higher than loads that initiate cracking

At 140, 000 lbs of applied load we can learn a lot 58

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Dundonald Trunk Sewer Installation History • Installed in 2010 and 2011 • 2010 Contractor had real difficulties in shallower cover installations – walked from job • 2011 General re-grouped and assembled new pipeline installation group • Life got a lot better 60

Dundonald Trunk Installation History 61 • Inspected in early 2012 after representative loading had been in place for up to 11 months – Structure of the pipe was performing in a manner consistent with the design intent • Pipe re-inspected in 2014/2015 and fully meets design intent

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What’s the moral of all this? • Extreme loads and complex construction requires extreme (but logical) measures: – Rigorous approach to design, manufacture, proof of design, installation, and confirmation that design objectives have been achieved – Collaborative approach between designer, manufacturer, and installer essential to process – Meaningful acceptance tests both in nature and timing to confirm design intent was achieved – Engineers duty to Owner and Contractor = √ 63

Closure recap…the designer’s duty 1. Perform a design function – – – Learn from past designs don’t c-job stuff you don’t understand Secure some real information about sub-surface conditions Actually do some calculations 2. Think about your duty to the Contractor – – Recognize reasonable means, methods, and techniques of construction Highlight areas that require extraordinary effort Minimize the caliber of gun you give him to cause his own demise Articulate your design concept clearly 3. Put reasonable Qa controls in place so that things don’t get screwed up – Or to make what does, a manageable fix 4. Put meaningful acceptance testing in place to confirm that the design intent was achieved 64

Engineer’s duty… my top 3 list 1. Engineers shall hold paramount the safety, health and welfare of the public and shall strive to comply with the principles of sustainable development in the performance of their professional duties. 2. Engineers shall perform services only in areas of their competence. 3. Engineers shall continue their professional development throughout their careers, and shall provide opportunities for the professional development of those engineers under their supervision. 65

Thank you… Chris Macey Americas Technical Practice Lead Condition Assessment & Rehabilitation of Pipelines 66