Discussing current issues in engineering
Conjuring an image of “nature” typically entails lush forests, deep canyons, sunsets over the horizon, or whatever your favorite landscape may be. The commonplace reason for “returning to nature’ has been a reset button for the overstimulated brains of the modern person. Viewed as separate, purer, and even foreign, some of the most fascinating elements of nature often go overlooked by the everyday passerby.
However, the concrete jungle that envelops most of the developed world seems to be creeping closer to its natural roots. Our deep admiration and awe of the non-human world combined with our obsessive drive to innovate is blurring the lines between the landscapes. Some of what we see as the simplest elements of nature are turning into impressive feats of engineering.
As the world refocuses on the Sustainable Development Goals, responsible engineering is at the forefront of what could be considered a metamorphosis. Organizations such as the Biomimicry Institute, Biomimicry 3.8, and a growing cadre of universities are creating nature-inspired solutions to help grow a healthier planet.
Our built environment is held together by a glue of concrete creating a bifurcating web between humanity and the more organic, non-human elements. The scale of concrete use across the planet is immense, with the industry accounting for roughly 7% of global greenhouse gas emissions. New research in materials science is harnessing the power of nature to reinvent concrete at its core. The profound technologies explained below, designed to mimic basic biology, could positively impact industrial sustainability for generations.
One example of such engineering is self-healing concrete. The smallest of cracks can grow the mightiest of oaks, but they can also create an unseen world of destruction, corrosion, and instability. Dilapidated infrastructure remains a pervasive issue, and researchers at Binghamton University and the State University of New York are working to nip this problem in the bud. Inspired by the ability of the human body to heal itself after injury, self-healing concrete uses a fungus called Trichoderma reesei to seal the fractures as they crop up. Fungal spores and nutrients are added to the concrete matrix during mixing and then lies dormant until the cracking first appears. When enough water and oxygen penetrate the split, the fungal spores germinate and grow. Precipitating calcium carbonate as a byproduct of the fungal growth, the cracks fill, cutting off the supply of oxygen and water and mending the break. The fungi again form spores and wait patiently for the next crack to appear.
Another engineering adaptation adopts lobster inspired patterns in 3D printed concrete. This method of manufacturing has the potential to improve time, effort, and material efficiencies in civil engineering design projects. By biomimicking the spiral patterns in lobster shells, 3D printed concrete enables strength to be directed precisely to areas needing increased structural support. Exoskeletons like the ones fabricated by crustaceans have evolved to harness key advantages in design for stability and performance. Emerging 3D printing technologies greatly enhance engineering productivity and will transform the way our built environment is created from the ground up. This layer-by-layer approach slashes costs, time, and enhances finished engineering projects by utilizing bio-mimicked combinations of printing patterns, material choices, models, and reinforcement options.
Our reliance on concrete to stabilize our environment is not without costs, however. Like we mentioned, the carbon emissions from producing 4 billion tons of cement per year will proliferate detriment to the atmosphere. Although extending its life through the self-healing and 3D printed innovations, researchers at Aalto University are trying to move away from concrete use altogether. Developing a bio-based coating for wood may be the answer. Prone to degradation from moisture and sunlight, wood is not always the first choice of building materials. However, researchers have harnessed the innate resiliency of trees in the form of lignin. This abundant wood polymer is often regarded as a waste product in biorefinery and pulp processing. It is estimated that between 60 and 120 million tons of lignin is isolated annually world-wide, and of that, 98% is incinerated. Therefore, the potential applicability of lignin as a coating material is huge. Currently, protective coatings are primarily petroleum-based and included environmentally harmful substances. Outperforming traditional synthetic options, a lignin-based sealant coating is a safe, low-cost, high-performing construction option. Again, nature has provided us with an anti-corrosive, anti-bacterial, anti-icing, UV-shielding, bio-mimicked alternative.
The global urge to meet rising sustainability standards continues to drive material transformations and bio-mimicked alternatives even further. The longevity, persistence, adaptability, common in both nature and humanity, enables us to see, and emulate, the gifts that reside just outside our industrial frame of reference. While basic biology-based innovations provide us with sustainable growth opportunity, they are also the sincerest form of flattery for the vastly beautiful and complex world we are a part of.
Aalto University. (2021, July 23). Bio-based coating for wood outperforms traditional synthetic options: Researchers turn a non-toxic residue into wood coating that resists abrasion, stain, and sunlight.ScienceDaily.RetrievedSeptember20,2021,from www.sciencedaily.com/releases/2021/07/210723105310.htm
Binghamton University. (2018, January 17). Self-healing fungi concrete could provide sustainable solution to crumbling infrastructure: New concept offers low-cost, pollution-free and sustainable approach to fixing concrete. ScienceDaily. Retrieved September 17, 2021, from www.sciencedaily.com/releases/2018/01/180117152511.htm
RMIT University. (2021, January 19). Bio-inspired: How lobsters can help make stronger 3D printed concrete. ScienceDaily. Retrieved September 17, 2021, from www.sciencedaily.com/releases/2021/01/210119102846.htm
Reeling from yet another natural disaster of catastrophic proportions, the US looks to the challenges in the South with exhaustion, relief, sadness, hope, and perseverance. The human condition, however adverse to change we think we are, has an uncanny ability to recover, adapt, and thrive time and time again. Even so, this dynamically precarious state of perceived reliability and safety provided by our infrastructure is an ever-thinning veil of comfort.
Perhaps, the sheer magnitude of what we face with respect to climate change is simply not able to be fully realized. Maybe the trust of the American people in antiquated infrastructure systems is too great. Although, positively, it may be something else entirely…
Throughout the previous decade, the world has watched history unfold as disasters such as Superstorm Sandy (2012), a once-every-500-year pluvial event in Michigan (2014), hurricanes Harvey (2017) and Michael (2018), a record-breaking 5 major storms in the Gulf (2020), and now the wrath of Ida (2021), ravage the terrain. The detrimental intensity of these natural upheavals consistently pushes the boundaries of what our society can withstand.
Currently, we are in the midst of a paradigm shift as epically proportionate as 21st century superstorms. Modifications in behaviors, mindset, and industrial progress are barreling through the engineering sector in the form of resilience engineering. Resilience, defined as “the ability to spring back into shape”, is an American ideal permeating to our culture’s core. New to the scene, resilience engineering is taking that nucleic ethos and applying it to design, maintenance, and restoration objectives for buildings, infrastructure, and our communities. The image of a single flower growing out of a sidewalk crack should no longer be the poster image conjured in our minds. Instead, picture a punching bag that always rights and centers itself no matter the blow.
As Ida’s destruction is fresh in our forethought it’s only natural to envision coastal resilience as the primary pinch point of infrastructure durability. However, the modern pressures on engineering cannot pigeonhole the sect into narrowly focusing on a single element of the changing climate and landscape. Resilience engineering works to address evolving threats to infrastructure, changing environmental thresholds resulting in extreme weather events, and disrupted timelines for necessary improvements regardless of size.
Crossing traditional disciplinary boundaries has become a foundational tool for civil and environmental engineers, and reliance on cooperative approaches will only increase. Tandem planning efforts for land use, environmental considerations, social and equity factors together inform infrastructure design and systems within resilience engineering.
Therefore, the not-so-streamline path of progress has been diverted, requiring a fresh focus on the first principles of the new paradigm. The foundation of today’s engineering has been trained to balance loads versus capacities and evaluate cost-benefit optimization. Through resilient design, engineers will begin to fill the cracks by; integrating physical and social design considerations, quantifying, and incorporating uncertainty, use system-level approach to plan for infrastructure diversity and redundancy, and explicitly defining adaptive options within design decisions.
There to meet the needs of the community, civil and environmental engineers can adapt to replace traditional standards-based approaches with risk informed project plans, providing tangible technical solutions for sustainable, resilient progress.
It may seem, at times, that we have strayed too far, and the wobble has turned in to a topple, and the complexity of system inter-dependencies, regulatory constraints, the evolving nature of hazards, the limitations of conventional engineering solutions, and the humbling effort required to work across disciplines is just too heavy a burden to embrace. However, we cannot stagnate. It is clear the data of the 20th century can no longer inform the resilience planning of the future.
The inadvertently short-sighted planning, development and disaster policy of the U.S. is now barely operating as a broken crutch bowing under the atmospheric pressure of climate change, population growth, and technological acceleration. This is an advantage for engineers though. The ability to leverage risk informed approaches in order to mitigate flooding and reduce hurricane or other natural disaster impacts further fuels the resilience paradigm shift, emphasizing recovery instead of loss reduction.
But how is resilience measured?
The first study defining the components of resilience was the Resilience Measurement Index. However, it largely missed the mark by failing to address ability of engineered systems to adapt. But, like humans, adaptability needs to be built into the code, the structural DNA so to speak, of the policies, ordinances, regulations, and expectations of foundational infrastructure resilience planning across community scales. Statistical assessments for measuring the level of resilience such as the Critical Infrastructure Elements Resilience Assessment (CIERA) and the HAZUS Resiliency Evaluation are only two great places to start incorporating into planning methodologies.
Resilience engineering is a cyclic process with a need for assessment and reassessment of the systems throughout their life. Quantification of resilience has to divert focus from the sticker shock of the damage and look to future cost saving. Mutating building codes, a much less taboo practice than the typical sense of the work, could ubiquitously create a new “hazard landscape”. Increased adoption and enforcement of the new expressions of civil and environmental engineering DNA will be the rebuilding blocks of natural disaster recovery.
Achieving dynamic stability through resilience planning is not without significant challenges. The geographic size and scope of modern infrastructure, interdependencies between communities, bureaucratic corruption, conflicting regulations, and cascading failures resulting from natural disasters all hinder the resilience engineering movement. However, responsible engineering can’t be accomplished in isolation, nor should it be attempted. Accepting failures within systems, the inability of infrastructure to offer complete protection from disaster, and the inevitability that change is going to happen, will foster the advancement in recognition of our need for resiliency and cognition of the path forward. As engineers, we must ask ourselves from the beginning how we can ameliorate the infrastructure and communities we are a part of by taking a leadership role within the paradigm shift. With this resilient mindset, civil and environmental engineers are perfectly poised to become the “true protagonists” of the rejuvenation of United States urban infrastructure, and stewards of the cities as we all head into the eye of the storm.
Baecher, Gregory, et al. “Resiliently Engineered Flood and Hurricane Infrastructure: Principles to Guide the next Generation of Engineers.” National Academy of Engineering, The Bridge, 1 July 2019, https://www.nae.edu/212181/Resiliently-Engineered-Flood-and-Hurricane-Infrastructure-Principles-to-Guide-the-Next-Generation-of-Engineers
Lu, Xinzheng, et al. "Quantification of disaster resilience in civil engineering: A review." Journal of Safety Science and Resilience 1.1 (2020): 19-30.
Rehak, David, et al. "Complex approach to assessing resilience of critical infrastructure elements." International journal of critical infrastructure protection 25 (2019): 125-138.
“Resilience | Definition of Resilience by Lexico.” Lexico Dictionaries | English, 2019, www.lexico.com/en/definition/resilience.
Colman Engineering, PLC
A professional engineering firm located in Harrisonburg, VA