The Heritage Group opened its new Innovation Center and Research Laboratory in Indianapolis in August 2017. While the building and lab is a state-of-the-art facility, the associated roads and parking lots were also designed and built with state-of-the-practice innovation, features, and engineering prowess to ensure optimal performance.

Too often, commercial development focuses on the facility itself with less emphasis on the pavement infrastructure. Pavement designs are often based on being the least initial cost with little concern for long-term performance. Construction can be rushed, with little oversight and inspection. Too often, the rush to get the facility open for business leads to the asphalt being placed in adverse weather conditions that should be avoided.

The Heritage Group has extensive experience designing and building pavement systems all over the world for a wide range of applications. They applied this experience in the design, material selection, testing, and construction of the pavements around their new center and lab.

Typical parking lot distresses

The team’s first task was to identify the failure mechanisms most often occurring on commercial asphalt parking pavements. They came up with the following:

Improper drainage — Parking lots have significant surface area and can collect water quickly. Proper drainage is critical to the long-term performance of the parking areas.

Cracking — Parking areas can show premature cracking, often at longitudinal joints or between concrete curbs at the interface with the asphalt. Cracks can also be caused by thermal expansion and contraction. Once water enters the pavement, expedited damage can occur from weakened subgrade, which then leads to fatigue cracking — sometimes described as alligator cracking.

Premature aging — Asphalt placement in parking lots typically requires significant hand work around structures. Besides the asphalt mix being more prone to segregation in these hand-placed areas, the compaction effort is often done with smaller rollers and is inconsistent. This results in pavements having high localized air voids, leading to high permeability of air and water due to interconnected voids.

Structural design — Commercial parking facilities tend to be structurally under-designed because of costs and underestimation of truck traffic. Local standards for thickness designs of parking areas typically vary based on subgrade strength and assumed truck traffic. It’s often assumed these parking lots will see no truck traffic, yet certain areas of the pavement such as delivery lanes see regular truck traffic and thus are under-designed.

Lack of fatigue resistance — Most parking lots never utilize premium materials such as modified asphalt binders that have polymers that can add flexibility and strength to the pavement. Modified asphalt binders can enhance performance, especially in high strain conditions, which are often the case in thinner pavement systems.

Unique features

The center’s final pavement designs utilized materials and features not typical of commercial parking lots or even roads.

Structural design — The roads were designed at 8 inches of compacted 36-mm top size aggregate base, with 4 inches of 19.0-mm Superpave hotmix asphalt (HMA), and two, 1-inch lifts of steel slag SMA 4.75 mm. The steel slag SMA 4.75 mm mix is identical to the current racing surface placed on the main oval of the Indianapolis Motor Speedway, but with improved binder properties. The parking areas were constructed using 6 inches of compacted #53 aggregate base, 3 inches of 19.0-mm Superpave HMA, and a 1-1/2-inch lift of 9.5 mm with dolomite.

Polymer Modified Asphalt (PMA) — Two polymer asphalt systems were selected. The roads used a PMA with a unique polymer combination that graded as a PG 82-22 (true grade 82-26) in the top two 1-inch steel slag SMA lifts. The parking areas used a PMA that graded as a PG 70-22 (true grade 74-24) in the 1.5-inch surface lift of 9.5 mm.

Mix performance testing — Performance testing was conducted on the surface mixtures, including IFIT (low-temperature cracking) and Hamburg (high-temperature rutting). Results were favorable.

Longitudinal joint sealant — Parking lots contain many longitudinal and transverse joints. The area around these joints tends to have higher air void levels, making them more prone to permeability, cracking, and raveling. An innovative technique to seal these joints from the bottom-up is called Longitudinal Joint Sealant (LJS) — named by the Illinois DOT.

The Heritage Group’s VRAM product is placed typically at a width of 12 or 18 inches on the underlying pavement by either a handheld drag box, push cart, or in-line spray bar, prior to the surface lift being placed. The heavily modified sealant is designed to wick up into the surface mix, thereby filling the voids around the joint, reducing permeability, increasing durability, and keeping the joint from opening up over time. Sealant was also applied along the concrete curb to create a flexible inner layer to keep the joint between the asphalt and concrete impermeable.

Low permeability — A void-filling emulsion was applied to all pavement surfaces. The emulsion (RPE) is designed to permeate into any interconnected voids of the surface mix, thereby making it impermeable. The unique penetrating qualities of this emulsion, along with careful application, is intended to leave little product on the surface and not adversely affect pavement friction.

Porous pavement design — In specific parking areas, a specialized porous pavement mix was placed with roughly 20 percent air voids to quickly drain the water. These porous layers have a subsurface collection basin that slowly releases to retention ponds. This eliminates flooding from stormwater runoff.

No bird baths — Before the surface lift was paved to all roads and parking areas, a survey was conducted to assess the ability to drain without ponding. A small milling machine was used to correct slope where needed to enable water to drain. Only a few small areas needed to be milled before the final surface lift was placed.

Conclusion

Too often, little attention is given to designing and constructing pavements for commercial properties. This can lead to early distresses, requiring crack filling and other repairs that are a poor reflection on the business. Innovative engineering and the use of premium materials should not just be reserved for highways. The design and construction of the pavements at Heritage Group’s new Innovation Center and Research Laboratory is an example of how long-term performance can be achieved, resulting in low maintenance and outstanding life-cycle costs long term.

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Mark Buncher, Ph.D., P.E., is director of engineering at the Asphalt Institute (www.asphaltinstitute.org). Tony Kriech is vice president of Research and Development at the Heritage Research Group (http://hrglab.com/rd.html). This article is reprinted with permission from the spring 2018 issue of Asphalt magazine, published by the Asphalt Institute.

We learn about landscape architecture through a study of context. Technical courses teach students to see the physical characteristics of a site. We learn to identify slope, follow the point of steepest grade in a trail of mud following a rainstorm, identify ecosystems. Theoretical courses teach students to see the intangible qualities of a site — the implications of design decisions upon usability. We learn about the exciting but unpredictable ways a site may develop and come to be used differently than originally intended.

Forward-thinking landscape architecture practice usually involves re-combining the physical and intangible characteristics of a site. Excellent waterfront and post-industrial redevelopment landscape projects have inspired a generation of landscape architects. “What can this become?” is the question that sets most of us on fire.

We imagine a behemoth dump as a park, breathing life back into a great metropolis. A concrete drainage channel transforms into a living waterway, mixed-use development, and microbreweries springing up like eddies along its length. Disused utility easements become oases for habitat in the most unexpected of urban places. We have also seen an increasing amount of “futuristic” landscapes, with high-tech features, such as interactive light or water, app-enabled components, and more.

But what of the impact of new technologies in our built environment? We have anticipated autonomous vehicles for some time (to little effect in our design decisions), but what of the possibilities of autonomous delivery vehicles, or average urban dweller navigating their day with the aid of a reality-enhancing headset, or the convenience/intrusion of biometric scanning as an Apple Pay-inspired method of negotiating daily life?

Without the human element, landscape architecture is not landscape architecture. Yet humans do not remain static and are now in the process of technology-assisted development. In light of these impending realities, what can landscape architects do to maintain an edge on the design of public spaces?

As a profession of such varied talents and individual specialties, there is a place for landscape architects as futurists. There exist landscape architects as ecologists, living systems designers, food system engineers, and health care amenity designers. Leafing through the ASLA annual meeting presentations is enough to inspire the most dispirited of practitioners with new possibilities.

A “futurist” is “a person who studies the future in order to help people understand, anticipate, prepare for and gain advantage from coming changes,” writes the Association of Professional Futurists (APF). This should resonate with landscape architects.

Whether we study the condition of a breakwater and local weather patterns in order to recommend an appropriate intervention or recommend a green roof or living system at an urban development project to address the urban heat island effect, we are in essence studying current conditions and predicting future trends in order to help people prepare for and gain advantage from coming changes.

A recent string of articles caught my eye. First, from an article on CNBC, April 21st, 2017: Robots are Now Delivering Food in San Francisco. Next, on Eater, May 17th, 2017: San Francisco Declares War on Food Delivery Robots. Also from May 17th, 2017, this time on technology blog Wired: San Francisco Tries to Ban Delivery Robots Before they Flatten Someone’s Toes.

The first article reports the San Francisco robots in question are run by a company called Marble, founded to re-think the “last mile” of the delivery supply chain. Their solution is meant as a step toward relieving vehicular and courier snarls during the final stage of delivery of small packages and items. The article goes on to refer to companies, such as Amazon, Alphabet, and Uber, which have also been investing this facet of the supply chain.

Following initial roll-out of the automated delivery system there was an offended backlash that follows an unanticipated offense, with calls to ban these small robots. The Eater article pegs the issue as one of insufficient policy paired with infrastructure. San Francisco city supervisor Norman Yee told them: “Our streets and our sidewalks are made for people, not robots. This is consistent with how we operate in the city, where we don’t allow bikes or skateboards on sidewalks.” When asked if he thought robots could safely run in a bike lane, Yee agreed it was something to think about: “Maybe in the future there will be robot lanes.”

It’s true that progress in urban policy integrating “last mile” delivery robots across the United States and internationally is being driven by robot companies that lead planning and policy initiatives, which can then result in a narrow definition of a municipality’s approved specifications that apply exclusively to that company’s product.

But the uproar was strange for a few reasons. First, given the city’s location adjacent to Silicon Valley, San Francisco residents and managers should not be unprepared for the introduction of automated systems to perform mundane tasks. Starwood Aloft hotels have been using a mobile automated system to delivery sundry items such as toiletries to hotel guests since 2014. Silicon Valley company Knightscope manufactures security robots which have been roaming buildings and industrial complexes in the Bay area for at least a year prior to deployment of Marble’s food delivery robots.

Second, as a dense West coast city with progressive urban development policies, it is surprising that San Francisco is resisting the benefits of a potentially-advantageous technological advancement. Delivery robots, especially when automated to follow given paths and arrive at specific locations (very possible using satellite mapping technology), represent a potential solution to a number of traffic headaches. The narrow streets of historic cities are often clogged by delivery trucks, a trend which is on the rise. Millennials in particular continue to invest in the convenience of home-delivered groceries, meal plans, clothing sampling services, and Amazon Prime for everything else.

This human behavior pattern has consequences for the health and function of our cities, and the policy and design response must adjust itself dynamically to accommodate such trends.

It is common in conversations with landscape architects and planners to arrive at mutual agreement about the antiquated views of traffic congestion wherein the cyclical solution is to simply add more lanes. Many praise the benefits of multi-modal transportation planning, transit-oriented development, and walkable complete streets to create healthier cities.

We must ask, however, if these views are becoming as antiquated as the automotive-focused interventions we disparage. Don’t we have technologies that can work now, complementing evolving human behavior, to produce a healthier system?

The landscape architect as futurist may be any of us of different professional specialties. We are, at heart, a profession made up of practitioners who study variations of environmental context and human influence. We have the opportunity to look to the future in order to help people understand, anticipate, prepare for and gain advantage from coming changes.

Our lifetimes will see dynamic shifts in the way humans co-evolve with technology. It is time for landscape architects to look creatively upon these changes, and ask with a futurist’s eye: what can this become?

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This guest op-ed is by Alison Kelly, ASLA, LEED AP ND, a landscape designer at O’Dell Engineering in Modesto, California. She has presented on culture, landscape, and learning at the Society for Applied Anthropology national conference and the Children’s Outdoor Environments professional practice network (PPN) at the ASLA Annual Meeting.

For most people, spending time outdoors in well-designed public spaces is one of the highlights to city life. Why, then, do we spend comparatively little time and money on designing them? In this article, originally posted on Metropolis magazine as “Designing Outdoor Public Spaces is Vital to the Future of our Cities” Kirt Martin, the vice-president of design and marketing at outdoor furniture designer Landscape Forms, makes the case that landscape architects and industrial designers working in the public realm are key for our cities’ health and happiness.

All of us treasure our time in outdoor spaces. So why do we devote so little of our attention to their design?

As a designer in the site-furniture industry, I am always curious about the value people place on the outdoors. I like to ask people I meet to describe a great city like New York, Chicago, or Paris and what they most remember about being there. Or I ask them, if they won $25,000 to spend on a dream vacation, where they would go and what they would do. Their fond memories of a celebrated city or an escape into the wild often have little in common, except for one thing: Their most memorable and meaningful experiences almost always revolve around the outdoors.

We have studies showing that people tend to be healthier and happier, and can enjoy longer lives, in areas where they have access to nature, including green urban spaces. Outdoor spaces are some of the least expensive to create and can pay some of the highest returns on investment—in terms of community life, health and wellness, and the generation of economic activity in surrounding areas. As more people—from young professionals to retirees—move back into cities, green public spaces and vibrant streetscapes are often cited as key factors for attracting residents and businesses.

Despite this, we do not give outdoor spaces the same value and financial support that we give to buildings and interiors. We calculate the square-foot dollar value of buildings and interiors but don’t do the same for a square foot outdoors. We have not made a strong business case for designed outdoor spaces—we can and should be making this case. I also believe that design and innovation in public and privately owned outdoor space is lagging—and the first step to address that challenge is to better leverage the skills and talents of landscape architects, the professionals best prepared to design them.

This is a time in human history when landscape architecture has something really important to say. We should listen. Landscape architects practice a discipline rooted in holistic thinking. They understand the natural environment, the built environment, and the interface between them. And they are ideally prepared to take leadership in shaping outdoor spaces and framing public awareness about them.

Recent high-profile projects such as the High Line and Millennium Park have achieved placemaking of the highest order, and the star landscape architects responsible for them have captured public attention. But there is a whole legion of talented, inspired landscape architects out there who should also be at the center of envisioning and designing outdoor space.

This is also a time when industry can play a constructive role. Those of us who provide the site elements that help shape and activate these spaces need to do our part, and I’m excited about taking on that challenge, researching methods to make the case for the return on investment for well-designed outdoor spaces measured in terms of community, identity, well-being, environment, and dollars spent. I am focused on driving innovation with new types of scalable solutions that go beyond the standard litter bin, bike rack, and bench, to help people enjoy great outdoor experiences. The outdoors starts only a half-inch outside the door, so we need new ideas for spaces adjacent to buildings. We also need to integrate technology in public spaces, but in ways that respect the special qualities of the environment.

I am excited by the work and believe that, in collaboration with landscape architects and other design professionals, all of us in the site-furniture industry can elevate awareness and promote greater investment in outdoor spaces that create memory and meaning. We can make a real difference in the urban landscape that is our future.

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Kirt Martin is the vice president of design and marketing at Landscape Forms, leading the company’s creative teams for product development, marketing, and marketing communications. Martin is an award-winning industrial designer, and previously directed design activities at Turnstone, a division of Steelcase.