Civil Engineering on our Seashore

This piece is about the varieties of Coastal Civil Engineering (CCE) works we all see – when visiting seafront to relax, to feel the warmth of ocean in continuous pounding of waves, or when seeing vessels navigating in and out of ports and harbors. These works result from engineering efforts that have three well-known tenets of civil engineering: coastal hydraulic engineering (or simply Coastal Engineering), coastal structural engineering and geotechnical engineering (structural and geotechnical are often lumped together as structures engineering). Coastal hydraulic engineering term is sort of a misnomer – because it not only covers analysis, modeling and determination of hydrodynamic forces caused by water, water level rise and fall, current, wave and bed-level changes – but also includes similar activities due to wind forcing. The combined effects caused by wind and water are known as metocean processes and forces.  
Before moving further it is important to build into our concept the extent of geographical area where civil engineering is referred to as CCE (to avoid confusion, CE is reserved to denote Civil Engineering). This area termed as the coastal zone – extends from the inland topographical limit reached by major storm surges and tsunamis to the continental shelf break. Continental shelf mostly of turquoise water, having an average bottom slope of some 1V:100H extends from the shoreline to a seaward line where the slope abruptly dips down into the ocean at about 1V:40H or steeper. This line begins roughly in the region where waves of about ≥ 10 seconds will start feeling the bottom – consequently being subjected to the transformative processes of refraction and shoaling (see Wave Transformation piece on this page). Generally, mariners call the blue ocean beyond continental shelf – high seas. The definitions of inland limit vary among countries – and depend on several criteria such as: technical, legal, administrative, disaster management and hazard insurance – but they all invariably include coastal waterways, river mouths, estuaries and bays. I have discussed many aspects of CCE in different pieces on the NATURE and SCIENCE & TECHNOLOGY (S & T) pages. Thought a piece of introductory nature will complement those.
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1. Coastal Boundary Definitions
In the US Submerged Land Act (1953) a coastline is defined as: the line of ordinary low water along that portion of the coast which is in direct contact with the open sea and the line marking the seaward limit of inland waters. The same Act defines coastal submerged land under the jurisdiction of coastal States as: navigable waters, and lands beneath, within the boundaries of the respective coastal states out to 3 nautical miles from its coastline. The Outer Continental Shelf Lands Act (OCSLA 1953) defines federal jurisdiction on coastal oceans as: all submerged lands lying seaward of state submerged lands and waters (e.g. outside shelf lands seaward of 3 nautical miles).
Perhaps it is useful to add a brief on the legal definition of Maritime Boundary. Part of this brief is based on my 1994 IEB paper: On the Formulation of Coastal Zone Management Plan for Bangladesh. The following definitions of the boundaries are agreed upon by signatory countries (including the land-locked countries which are given the right to claim maritime transport access through their coastal neighbor) at the UN Convention on the Law of the Sea (UNCLOS 1987). It was developed and refined within the framework of the UN – during a period from 1970 to 1984.

• To define and demarcate different zones a reference line is required – and this reference line termed as the Base Line (BL) is defined as a delineated shoreline at Mean Low Water (MLW). The BL is delineated to include a country’s nearshore/offshore islands, if any, along with a straight line to enclose bays and estuaries.
• Inland Water (IW): the waters landward of the BL.
• Territorial Sea (TS): the seaward water from the BL to the extent of 12 nautical miles (NM) or ~22 km.
• Exclusive Economic Zone (EEZ): the seaward limit to the extent of 200 NM (~370 km) from the BL. An intermediate Contiguous Zone (CZ) is also defined outside of the TS – seaward to the extent of another 12 NM. One can imagine that with such definitions of BL, TS, CZ and EEZ – each of them represents a series of polylines, roughly mimicking a country’s coastline. A country defining these boundaries owns these waters and has the jurisdictional authority over them: authority to develop and exploit Natural resources (e.g. mineral, fisheries) within its EEZ; authority to control maritime traffic, and to react if a hostile vessel enters its TS without permission. It also has the responsibility to maintain the waters pollution-free and take care of its flora and fauna. A country’s Coast Guard is given the authority to enforce the rights and responsibilities.

Despite the clarity of definitions – legal interpretations differ and disputes often arise – such as the two flashpoints – the Arctic Sea and the South China Sea. As far as the maritime traffic is concerned, the sea beyond the TS – the High Seas belongs to all nations. Note that the definitions of these boundaries have nothing to do with bathymetry (for example, the zone boundary is not affected whether it is a wide or a narrow continental shelf). However, the boundary limit has to be measured along a line perpendicular to the BL. Each country and international organizations issue marine charts showing the demarcated maritime boundaries.
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2. Engineering, Civil Engineering and Coastal Engineering
2.1 Definitions
Engineering has always been and will always be – the practice of finding ways to derive workable and applicable solutions. To that end engineers search for relevant scientific findings to approximate and adapt them to their needs – but with the fundamental principle of causes ↔ conditions guiding them. Approximation, Truncation, Adaptability and Scaling – are some of the key words in an engineer’s vocabulary and tool box – that help him or her to generate an array of alternative solutions. Different screening factors such as cost-effectiveness, safety, soundness and constructability impose their weights in narrowing down the choices – to the One that is expected to have minimum impacts on the surrounding. With these words of important understanding, let us move forward delving into some definitions.
As for the domain of CCE that focuses on some particular aspects - are names like port and harbor engineering, maritime engineering (coined first in European literature), and marine engineering. The last term is loosely applied in civil engineering to describe in-water works – but its root mainly lies in describing mechanical-electrical engineering, navigation and naval architectural aspects of seafaring vessels. Ocean engineering, oceanographical engineering and offshore engineering terms are also used to describe works in coastal and deep waters. Offshore engineering term is primarily applied to describe isolated in-water works in deep water – like oil terminals and marine pipelines.
There are many definitions of CCE – different in wording but common in contents. Let us attempt to define it in this piece as: CCE refers to the practice of planning, designing and effects assessment of civil engineering works for the protection and preservation of, and for developments of: water-front townships and cities, recreation, marine transports and installations, and value-adding improvements within the coastal zone. The history of CCE is briefly discussed in the Resistance to Flow on this page – it is a fairly new discipline – the official recognition and definition was launched only about 70 years ago – at the First Conference on Coastal Engineering held in Long Beach, California in 1950. Coming back to the definition – one can see that it relies on the understandings of two other terms: civil engineering, and engineering. There are many definitions of these two terms in literature, but I prefer using the following two.
According to The National Academy of Engineering and National Research Council: engineering is the study and practice of designing artefacts and processes under the constraints of the laws of nature or science and time, money, available materials, ergonomics (it is the process of designing or arranging workplaces, products and systems to satisfy the needs of people who use them) environmental regulations, manufacturability, and repairability.
In NAP #12635 Publication the following texts elucidate the understanding of engineering practices in a very detailed and useful manner (I have rearranged the lines somewhat for clarity).
Engineering “habits of mind” (refer to the values, attitudes, and thinking skills associated with engineering; AAAS 1990) align with what many believe are essential skills for citizens in the 21st century. These include:
(1) Systems Thinking: systems thinking equips students to recognize essential interconnections in the technological world and to appreciate that systems may have unexpected effects that cannot be predicted from the behavior of individual subsystems;
(2) Creativity: creativity is inherent in the engineering design process;
(3) Optimism: optimism reflects a world view in which possibilities and opportunities can be found in every challenge and an understanding that every technology can be improved. Engineering is a “team sport”;
(4) Collaboration: collaboration leverages the perspectives, knowledge, and capabilities of team members to address a design challenge;
(5) Communication: communication is essential to effective collaboration, to understanding the particular wants and needs of a “customer,” and to explaining and justifying the final design solution; and
(6) Attention to Ethical Considerations: ethical considerations draw attention to the impacts of engineering on people and the environment; ethical considerations include possible unintended consequences.
The 2008 ASCE BOK2 (Civil Engineering Body of Knowledge for the 21st Century, 2nd ed.) defines and elaborates civil engineering as: the profession in which a knowledge of the mathematical and physical sciences gained by study, experience, and practice is applied with judgment to develop ways to utilize, economically, the materials and forces of nature for the progressive well-being of humanity in creating, improving and protecting the environment, in providing the facilities for community living, industry and transportation, and in providing structures for the use of humanity. All these definitions are quite lengthy, but they were developed to cover all different aspects – from scientific, technical, ethical-legal, and societal perspectives. 
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2.2 An Engineer's Freedom and Creativity 
As discussed, in every definition of engineering – creativity is described as an important element of the profession. It is described as one of the fundamental requirements of engineering practices and management philosophy. But, what does this engineering creativity mean exactly? Let’s attempt to examine this question closely focusing on civil engineering.
Oftentimes a pertinent question disturbs an engineer’s mind. This important question is, to what extent an engineer can be creative. Creativity connotes freedom – freedom of choice, freedom of alternative thinking – and its sharpness and appeal depend on an individual’s level of skill and experience - of the originality of approaches and innovation. Does an engineer enjoy professional freedom like others within the compliance constraints of standards, codes and individual licensing? Dubbed as the best-practice guidelines, they come with authority – to the likeness of an overlord. 
If one goes back in time – one would find that the nature of the broad field of technical, skilled craftsmanship and engineering profession – has evolved from one of freedom and creativity to the controlled Industrialization way of managing things – of narrowing down definitions in categorization of disciplines to streamline industrial productivity. Some aspects of them are briefly touched in – 1. Freedom of Thinking and Creativity and 2. Ancient Civilizations that Stand Tall of Turning The Wheel of Progress – and in 2. Historic Hydraulics Engineering Marvels of Common Sense Hydraulics.
Among many ancient and pre-industrialization engineering marvels – that stand out to our admiration are the Chinese traditional nail-less interlocking wooden architecture dating back to the 7th millennia BCE, the 3rd millennia BCE Egypt Pyramids, the 7th century BCE Great Wall of China, the 5th century BCE 1776 km long Hangzhou-Beijing Grand Canal of China, the 3rd century BCE Roman Aqueduct . . . the 8th century CE Borobudur Indonesia, the 12th century CE Angkor Wat Cambodia, the 15th century CE Inca Machu Picchu mountain top citadel in Peru – and many others scattered all across the globe. Imagine the freedom and creativity of the master craftsmen during those times. They continuously explored to understand the balance and equilibrium of Nature – to define ways to sharpen their skills and tools – to create engineering marvels that stand out today and in time to come.
Before going further – it’s important to say that at a personal level – all enjoy certain freedom as a human being – and we use this freedom to be creative in our many day-to-day works. So, this level of creativity is always there – it is part of human intellect in attempts to see things differently – whether one is an engineer or something else.
With this, let us attempt to address some of the questions raised.
First, engineering creativity is not like the creative works of many – for example, of an artist. An artist’s creative works are non-conformal and have a very wide latitude of freedom to explore, experiment and create. These works of artistry ranging from painting, sculpture, music, poetry, novels to various artistic crafts – of fine arts and literary works – are deemed to and do inspire people to go to the direction of niceties in human life – peace, happiness and harmony. Essential to longterm healthy social wellbeing – they are fine examples of human creativity – and do not carry any risk to public safety.
Even journalists, media and politicians enjoy huge freedom. They function within the broad umbrella of societal standards and ethics, but do not have individual licensing compliance code to abide by. Playing with words, lines and phrases – they thrive by capturing peoples’ emotion and attention to make profit. If they say something wrong today – they can easily correct it next day without suffering any repercussion whatsoever. The practice yields short-term gains at the cost of longterm harmful consequences. Erroneously, the works of these professions are also considered free of risk to public safety.
For an engineer, conformity requirement and various jurisdictional compliance codifications are designed to regulate his or her works. Although theoretical definitions and expectation say otherwise – within this net of compliance regulation – in reality, an engineer’s freedom becomes restricted, thus affecting his or her creative zeal. Therefore the short answer to the question, to what extent an engineer can be creative – is: an engineer does not enjoy much of a freedom like others – therefore has less latitude to be creative. The freedom goes so far as to the creative efforts of determining and balancing acts - of forces and strengths to ensure stability and safety of engineering works - and in the management aspects of them at various levels. In other words, an engineer's creativity is based on his or her level of skill and experience. For example, if someone comes with some sort of a technical problem - an engineer looks at it and figures out what to do and how to fix the problem. This, what to do and how to fix is the crux of engineering creativity. 
As well, while all engineers can question the scientific merit of methods and tools they use – practicing engineers have limited scope to go beyond standards and codes. One must not forget that despite the length of experience – a practicing engineer depending on the extensive use of regulatory standards and codes has the risk of losing Scalabilty Prowess – thus incapable of developing into an expert engineer over time. Further, they work within the project delivery constraints of scope-cost-schedule. Efforts to balance this constraint affect an engineer’s freedom and creativity.
In an attempt to qualify the level freedom, thus creativity – let us try to understand the issue further – by categorizing the types of works an engineer does. For the convenience of discussion, four different categories of the engineering profession are proposed. They are described on the basis of the underlying principle that safety is paramount to an engineer – in his or her attempts to minimize Risk. While standards and codes dictate the works of all categories as the minimum requirement – the level of freedom varies from the high of level A to low at level D - in relative terms, let's say from less of conformity requirement to more of it. Subject to contractual outlines, the categories from B to D share the same responsibility in different levels and degrees for the  soundness and performance of a project.
Class A Engineering Freedom: Subject to funding constraints, those of our engineering colleagues who work in academia and research belong to this class. They have a mandate to be investigative and creative to generate means and methods to benefit engineering profession – and broadly the scientific community. Sometimes they also interact with the other categories of engineers in an advisory capacity.
Class B Engineering Freedom: It includes – all kinds of engineering studies ranging from developing concepts to pre-feasibility and feasibility studies – to Modeling activities of processes and products to understand them better – to facilitate better engineering judgments and installations. Many facets of engineering consultancy works belong to this class. Water modeling is like a piece of science and art, where one can have a synoptic view of water level, current, wave and sediment transport, and bed morphology within the space of the model domain simultaneously – this convenience cannot be afforded by any other means.
Class C Engineering Freedom: All engineering design activities, in particular the routine ones belong to this class. This category enjoys less freedom than the former two – their works are limited to compliance with the guidelines of Standards and Codes as a minimum. Many of them work under the umbrella of an architect’s freedom and creativity. But, they can question the merit of such standards, in particular of those that deviate from routine designs. In such cases, they can refer the encountered cases to further investigation – or given the scope, can undertake the investigation themselves.
Class D Engineering Freedom: The engineers in the construction industry belong to this class. While they must comply to design specifications – they may face many practical situations where the designed system may not fit the implementation detail constraints. In such cases – their experience and judgment are required to find creative solutions in consultation with the professionals of Class C Freedom Category (who have the upper hand to approve any change or modification) – or even to Class B category in rare cases. 
As highlighted in 4.1 Engineering Profession of The Grammar of Industrialization – perhaps Class A and some works of Class B, C and D belong to what the 1955 Grinter Report (Prof. Linton E Grinter, ASEE Link) called the professional-scientific – in contrast to professional-general of other works of the same classes. Prof. Grinter argues in favor of this separate labeling as . . . there is a great deal of similarity, both in conceptual understanding and in analytical methods, among the generalizations of heat flow, mechanics of fluids, electromagnetic fields, and vibration theory. When a student understands these generalizations, he has gained a concept of systematic orderliness in many fields of science and engineering; he is therefore able to approach the solution of problems in widely diverse fields, using the same analytical methods. This unification of methods of analysis can be accomplished to a considerable degree without reaching beyond undergraduate mathematical levels . . .
On what extent planning studies and design activities need to go in the direction of freedom and creativity, he argues . . . The capacity to design includes more than mere technical competence. It involves a willingness to attack a situation never seen or studied before and for which data are often incomplete; it also includes an acceptance of full responsibility for solving the problem on a professional basis. . . and creative thought and imagination are brought to bear in producing an integrated system. To do this is a difficult and challenging job, but a very necessary one. . .
An ASCE Collaborate Thread – discusses the issue further with multiple contributors participating.
On AI impacting engineering freedom and creativity – it is highlighted in 5. AI and the Future of the Artificial Intelligence Essay as . . . Sooner or later, the professions of technical and engineering activities – are likely to face decreasing involvement of human work force – also in the manner of adapting to the work environment with AI as a new team mate. One particular reason for this likelihood is that – many in this professions enjoy less freedom within the strict controlling framework that regulates them . . . Such a mechanistic framework is the ideal case for machines to creep in – for AI eating away some of the jobs.
In the Creativity and Due Diligence piece I have written that, CCE as a creative profession has the role . . . in the discipline of civil/hydraulic engineering, applied science provides the baseline knowledge on data and analysis, while technology provides tested products and materials. The role of an engineer is to find solutions to a given problem using resources from these two sources. To do it successfully, it is important for engineers to understand the necessary basics of the S & T. Failing in this matter affects the soundness of an engineer’s judgment. Therefore engineers are part of the S & T endeavors by being intricately involved in the development and progress – sometimes working at the forefront, but most often in the practical applications of science and technological advances to the real-world problems . . . And to accomplish that, engineers by and large, and perhaps more than any other profession – spend a significant portion of their time on computing to create acceptable, defensible and implementable solutions in quantitative terms – using slide rule in earlier times (until about 1970s) to the scientific calculators and personal computers in modern times.
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3. Coastal Engineering Envelope
Perhaps it is helpful to enumerate some of the sub-disciplines commonly included in the coastal engineering envelope. The first group (a-group) of activities includes those – aimed at establishing critical planning and design conditions and criteria by envisioning the most probable operational and design loading scenarios, uncertainties and risks for various interventions/structures (these structures not only include hard measures of concrete, steel and stones; but also soft structures like beach nourishment and coastal vegetation/tree barriers) based on analysis and modeling of various environmental parameters. This group includes:
(1a) hydrodynamics: water level, current, and wave;
(2a) wind climate and storms; and
(3a) sedimentary climate: coastal geology and sediment transport processes.
The second group (b-group) of activities utilizes the first – for planning, designing and assessing the effects and risks of:
(1b) coastal zone development and value adding;
(2b) coast and shore preservation and protection;
(3b) intakes and outfalls;
(4b) dredging and spoil disposal;
(5b) coastal waterfront and marine terminal structures, including marina; 
(6b) offshore and pipeline structures; and
(7b) port and harbor developments and structures.
I have included an image of the coastal envelope showing the discussed disciplines. As indicated earlier, Water Modeling is an integral part of CCE activities.
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4. Engineering Project Phases
An engineering project starts with a very limited knowledge – starting from that, the project moves forward to develop criteria, conditions, specifications, etc. in distinct phases of activities. At the first of three phases – the Conceptual Phase (known as Pre-FEED {Front End Engineering and Design} in Oil and Gas Industries) – starting from scratch, problems are defined and the project is visualized, they are then translated into a complete solution package (analysis and design sketches, alternatives, economics, etc) – only at a high level by utilizing available regional and site-specific (mostly unavailable) information. This phase is usually preceded by very high level technical feasibility and economic viability studies. At the next phase – known as the Preliminary Phase (FEED in Oil and Gas Industries) – the conceptual package is critically reviewed, a site-specific information base is established by measurements and modeling, new alternatives are generated, and the conceptual package is revised and updated – but the issued design sketches and specifications are not yet ready for implementation. At the Final or Detailed Phase – a final critical review of the preliminary package is undertaken – updated and refined where necessary, usually no new alternatives are generated – construction, monitoring and supervision methodologies are laid out by detailing each nut & bolt – and the final design sketches and specifications are issued for implementation with the consultant having the additional task of selecting a contractor.
The above phases are usually conducted by different engineering consulting firms for better accommodation of talents and ideas, but often the final phase is eliminated entirely for large projects – by combining the final design and construction into a single package. One prominent form of this system is known as the Engineering, Procurement and Construction or EPC method, where the contractor is responsible for the final design, procurement of materials, and delivering the finished functioning product to the client. To assist and oversee the EPC contractor activities – the project owner usually engages a specialist firm known as the Project Management Consultants (PMC). Apart from these, there are many other consulting, contracting and management terms used in different project phases and construction – and they are usually not the same across civil engineering projects – but vary according to types, even from one country to another.           
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4.1 Design Criteria
A little note on design criteria – they refer to the parameters that must be applied as a minimum for designing project elements; and mostly include: (1) environmental metocean forcing functions, (2) configuration and layout, (3) structural material strength, durability, etc (4) structure-geotechnical, (5) construction and construction foot-prints, (6) operation and maintenance, (7) economics, (8) safety and emergency access, (9) ergonomics, and (10) environmental effects. Some of these criteria are established by scientific and engineering analyses; others come from certified standards and codes; and client and regulatory requirements. Any lapses in not taking proper account of the above criteria constitute a failure.          
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5. Outline of Some Typical Coastal Engineering Works
Having clarified the meanings of different terms let us move on to the rest. Let me begin by listing some of the major works identified with coastal engineering. The list is long – I am tempted to provide a brief outline of some important works that are applied worldwide affording developments of manuals, standards and codes (see more in The Grammar of Industrialization):

1. beach drain {perforated underground drain placed in the swash zone},
2. beach nourishment {placement of imported sands to build new beach and/or to counter-balance beach erosion},
3. breakwater {an in-water self-standing protection structure - shore-attached, detached or offshore - to diffract, break and obstruct waves},
4. bulkhead {retaining structure to protect coastal inland from wave attack},
5. dolphin {port structure – usually a cluster of piles for mooring}
6. floating breakwater {pontoons anchored to seafloor or fixed to guide piles to attenuate mild wave actions; primarily applied to develop Marina where pleasure boats are housed and moored by tying them to finger floats},
7. groin {shore-perpendicular structure spaced suitably to minimize beach erosion},
8. jetty {shore perpendicular structure placed on both sides of inlets to keep navigation functional by interrupting longshore transports},
9. offshore breakwater {submerged or emerged structure to minimize wave action and beach erosion},
10. pier {port structure extending into water for loading and unloading}
11. pile structure {series of piles integrated together by pile caps to support superstructure},
12. pipeline {seabed pipeline to transport liquids and encasing cables},
13. quay {port structure – paved bank or built-up area for ship mooring, loading and unloading}
14. revetment/riprap {shore-parallel stones or manufactured concrete slabs laid on coastal slopes to prevent erosion},
15. sea dike {shore-parallel elevated earth or concrete structure to prevent flooding),
16. seawall {shore-parallel water-front structure to prevent erosion, overtopping and flooding},
17. scour protection {primarily stone ripraps to prevent structure undermining by scour},
18. sluice {drainage outlet generally placed on sea dikes to flush out inland water, and prevent salt-water intrusion},
19. storm surge barrier {structure placed on inlets, estuaries or river mouths that can be closed during storm surge and tsunami onslaught},
20. submerged sill/reef {placed in the nearshore to minimize wave action and beach erosion; the same concept is also often configured to facilitate wave surfing},
21. terminal {fixed or floating marine terminal, platform structure for mooring of ships, loading and unloading}
22. trestle {port structure – rigid frame of short spans used as a support for loading and unloading}
23. training wall {structure configured to direct flow to improve navigation and mooring}
24. wharf {port structure – where vessels can moor alongside for loading and unloading}                   

Aspects of these coastal and maritime port structures – the scientific, planning and design aspects of them are discussed in the following articles.
On Science of Nature Page:
Ocean Waves; Sea Level Rise - the Science; Coastal River Delta; Linear Waves; Nonlinear Waves; Spectral Waves; Turbulence; Coastal Water; The Hydraulics of Sediment Transport; Waves - Height, Period and Length; Warming Climate and Entropy; Characterizing Wave Asymmetry
On Science & Technology Engineering Page:
Common Sense Hydraulics; Uncertainty and Risk; Transformation of Waves; Resistance to Flow; Water Modeling; Sea Level Rise - the Consequences and Adaptation; Tsunami and Tsunami Forces; Storm Surge; The Surf Zone; Wave Forces on Slender Structures; Ship Motion and Mooring Restraints; Wave Structure Interactions & Scour; The World of Numbers and Chances; Managing Coastal Inlets; Propwash; Flood Barrier Systems; Breakwater; Harbor Sedimentation; Uncertainty Propagation in Wave Loadings; Force Fields in a Coastal System; Coastal Ocean Currents off Rivermouths; The Grammar of Industrialization - Standards, Codes and Manual; Coastal Water Level
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6. Characterizing Engineering Failures
How does one characterize the failure of a structure – like the listed ones? Failures generally fall into 4 basic types: (a) environmental load failure (the cause for this failure is attributed to the exceedence or unexpected occurrence of design loads and loading conditions), (b) functional or ergonomic failure (although the structural integrity remains intact, the structure fails to provide its designed operations, functions or performance), (c) structural failure and (d) geotechnical failure. The last two could have the following 3 causes:

• design failures of the structure – wholly or partly including its foundation – are caused by designed elements’ inabilities to withstand the loads used in the design;
• construction failures are caused by incorrect or bad construction and/or use of unspecified low-quality construction materials and methods – in violation of the design and construction specifications;
• deterioration failures are caused by inadequate or lack of repair and maintenance, specified in the design.

Each of these general failure modes and specific ones – defines the Limit State. A design process examining each state individually – constitutes what is known as the Limit State Design. According to the 2003 SEI/ASCE 7-02 (2nd ed.), Limit State is a condition beyond which a structure or member becomes unfit for service for its intended function (serviceability limit state) or to be unsafe (strength limit state). A 2012 ASCE Aspirational Guide Book on aspects of ensuring Project Quality - is an essential handy reference for engineers and non-engineers alike.
Here are few more relevant definitions taken from British Standard – BS 1990-2002, Basis of Structural Design 2010. design working life: assumed period for which a structure or part of it is to be used for its intended purpose with anticipated maintenance but without major repair being necessary . . . hazard: . . . an unusual and severe event, e.g. an abnormal action or environmental influence, insufficient strength or resistance, or excessive deviation from intended dimensions . . . limit states: states beyond which the structure no longer fulfils the relevant design criteria . . . ultimate limit states: states associated with collapse or with other similar forms of structural failure . . . serviceability limit states: states that correspond to conditions beyond which specified service requirements for a structure or structural member are no longer met . . . reliability: ability of a structure or a structural member to fulfil the specified requirements, including the design working life, for which it has been designed. Reliability is usually expressed in probabilistic terms. NOTE Reliability covers safety, serviceability and durability of a structure . .
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There are many more features of CCE, but for the sake of brevity, I like to stop at this, only to point out one very important aspect. Coastal structures are not like a tall building standing on a dry land – and they should not be treated as such. Because of their exposed location in water or at the water-front, they continuously come under attack by the dynamic and uncertain metocean forcing – from regular to extreme. They must withstand different aspects of the force fields - during construction and operational lifetime, as well as face the consequences of uncertain fluid-structure interaction processes, and have to cause minimum impacts on the surrounding environments.
Therefore the role of a coastal engineer is very crucial – not only in the establishment of design and operational conditions and criteria, but also during the process of planning, design and construction. Lack of effective coordination, cooperation and concordance among various disciplines – or perhaps in not recognizing the proper roles required of certain disciplines – could lead to earning bad reputation, and to risks of incurring serious economic losses.       
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I like to finish this piece with some lines of poetry written by a seemingly unknown amateur poet, but the poem was made significant by Saint Mother Teresa (1910 – 1997; Nobel Peace Prize 1979; Bharat Ratna 1980; Sainthood 2016) who displayed it in her office.

People are illogical, unreasonable and self-centered
Love them anyway.   
. . .
Give the world the best you have and you’ll get kicked in the teeth
Give the world the best you have anyway.
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What motivation went into such portrayals of the societies we live in – and the strength and courage the poet was asking for? One can hardly afford not to like the poem – but perhaps more so by a personality none other than Mother Teresa – because it tells all about her life and experience.

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- by Dr. Dilip K. Barua, 5 February 2019

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