Concrete Technology 2021

Greener Every Year and 35% Stronger

In our era of “carbon neutral” construction materials and green energy trends, the term “green concrete” has evolved to describe an environmentally friendly construction material.

The term “green concrete”, not so many decades ago, used to describe the condition of freshly poured ready mix concrete in construction projects or precast concrete products that required more curing time to achieve its full average 3,000 psi strength. The term “green” as applied to concrete was all about quality control.

Now, in our era of “carbon neutral” construction materials and green energy trends, the term “green concrete” has evolved to describe an environmentally friendly construction material.

Recycling and Concrete
Concrete is the most durable construction material in the world, and like the concrete used by the Egyptians to build the pyramids, an incredible 5,000-year lifespan for concrete structures isn’t unusual. But with the ever-changing demands of human civilization, the demolition of old obsolete concrete buildings and structures is inevitable.

But what can be done to dispose of the concrete rubble, a construction material with such incredible resilience to the elements that it’s not going to break down naturally in landfills any time soon? The answer is simple. Use the old concrete to make the aggregates for new concrete.

Fortunately, the crushing characteristics of hardened concrete are nearly equivalent to natural rock. That means that the original quality of the recycled material isn’t a factor, except for the poorest quality original concrete. As an aggregate for new concrete, the recycled rubble actually has advantages. Since all the original aggregate components are there as well as the existing hydrated cement paste, recycled concrete aggregates add more to enhance binding and strength characteristics than virgin crushed rock and sand alone.

With over 70% of the world’s population living in structures that contain concrete, the most natural disaster-resistant building material available, only one other substance on the planet is consumed more by human society. That substance is water.

Under increasing environmental pressures, diverting concrete waste from landfills is another top priority for the industry.

New Research
In the US more than 55,000 miles of highway are paved with concrete. With such widespread use, scientists are constantly looking for innovative ways to make concrete even more resilient by increasing strength and heat resistance with new additives and aggregate enhancements.

Now scientists from Australia’s RMIT University may have come up with a win/win solution in the search for better concrete construction materials with a new recycled concrete aggregate that’s a superior choice for paving those 55,000 miles of highway.

In his informative January 2021 article at New Atlas Nick Lavars reports on how RMIT research has led to the addition of recycled rubber tires and concrete demolition rubble in the traditional time-proven concrete formula of portland cement, sand, crushed rock, and water. First developed for paving, the RMIT team is now moving on to develop the innovative recycled concrete formula for precast concrete products.

Arcosa Specialty Materials provides Gypsum Dihydrate and Gypsum Anhydrite to the largest cement manufactures in the nation. Our sister company, Arcosa Aggregates, has concrete recycling facilities.


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How construction companies are adjusting to the coronavirus

As the coronavirus (COVID-19) brings countless businesses to a grinding halt, the construction industry remains resilient – even in the face of tremendous challenges.

Unlike many industries where “working from home” and “drive-thru service” are feasible countermeasures, construction firms have jobsites to run. Chris Hopper, executive vice president and general manager of Skanska, told the Cincinnati Business Courier : “You can’t hang drywall from your house.”

Skanska is a New York-based construction and development firm with projects throughout the country. The company employs more than 10,000 workers, and has developed a multi-faceted COVID-19 response plan to help keep employees safe and jobsites operational.

14 essential elements of a COVID-19 response plan for contractors

  • Understand and follow CDC guidelines
  • Place restrictions on travel
  • Develop screening measures for employees who have recently traveled
  • Instruct employees to stay home if they are feeling sick
  • Place restrictions on in-person meetings and other employee gatherings
  • Encourage employees to work from home if feasible
  • Train all employees on the 6-ft. distancing rule, no handshakes
  • Establish thorough cleaning protocols at offices and jobsites
  • Increase the availability of cleaning supplies and handwashing stations at offices and jobsites
  • Donate N95 respirator masks to local hospitals
  • Tell elected officials to put partisan bickering aside in this very critical moment of national crisis
  • Establish dedicated and empowered COVID-19 response teams
  • Stay up to date on both federal and local COVID-19 developments
  • Maintain clear, honest and ongoing communication with employees and subcontractors, and perhaps clients and suppliers
  • Best practices to mitigate exposure

Social distancing is a critical component of any COVID-19 response plan. Turner Construction Co., a New York-based firm that employs roughly 10,000, has begun limiting the size of employee gatherings and has already suspended large group meetings, including events such as conferences. Remote conferencing technology is now being utilized for meetings.

On that note, Turner Construction has expanded its network capacity and training tools to accommodate this surge in online network activity.

Social distancing is a critical component of any COVID-19 response plan. Turner Construction Co., a New York-based firm that employs roughly 10,000, has begun limiting the size of employee gatherings and has already suspended large group meetings, including events such as conferences. Remote conferencing technology is now being utilized for meetings.

On that note, Turner Construction has expanded its network capacity and training tools to accommodate this surge in online network activity.

Sometimes, an essential meeting that requires in-person attendance must take place. Turner Construction mandates that these meetings occur in spaces allowing for adequate social distancing, which, following CDC recommendations, keeps people roughly six-feet apart. Additionally, Turner Construction is adapting standard operating procedures to limit the number of employees in an elevator or hoist at a given time.

Harkins, an employee-owned construction company based in Maryland, constantly reminds employees about the six-foot rule. Additionally, sick employees are sent home immediately. All gatherings such as lunches are forbidden, and all meetings are now conducted remotely via Microsoft Teams.

Monitoring employees who travel has been another point of focus for construction companies. Skanska issued a ban on all international travel through at least April. Domestic travel has also been greatly limited.

Turner Construction has restricted all business travel to any CDC Level 3 country, which is a country deemed to have widespread transmission. Also, if any employee had traveled to or had close contact with anyone who traveled to one of these countries, that employee is not allowed onto a Turner jobsite or office for 14 days from the date of contact.

Taking it a step further, any employee who exhibits any of the common COVID-19 symptoms, including fever, coughing and restricted breathing, is instructed to stay away from Turner jobsites and facilities.

Promote good hygiene

Hygiene has also been at the top of the list for Turner Construction. All jobsites are required to provide access to hand washing stations, and staff

Construction industry hit hard, even as states deem it an ...

has been trained to clean and disinfect frequently-used objects such as lunch tables, coffee machines and doorknobs.

Harkins, meanwhile, has instituted a long list of jobsite protocols to help improve awareness. For example, CDC and OSHA guidelines are now posted in all conspicuous locations on jobsites, and jobsite leaders are trained to closely monitor employee behavior to ensure that the guidelines are being followed.

Harkins has also taken steps to step up jobsite cleaning. Trailers are now cleaned daily. Furthermore, a commercial cleaning service is brought in to clean and disinfect certain areas of a jobsite if COVID-19 exposure is suspected to have taken place. Harkins has also increased the volume of hand sanitizing products deployed to jobsites.

Establish and empower dedicated teams

Skanska has established a Coordination Response Team in each market it serves. Teams are tasked with monitoring COVID-19 developments, sharing information with employees and business partners, and implementing protocols.

Safety and Health Topics | COVID-19 | Occupational Safety and ...

Turner Construction has also established a dedicated COVID-19 Action Team to support employees. Support is a key element that can get overshadowed in the midst of this crisis, and employers can play a constructive role in helping people cope.

On that note, Turner’s COVID-19 Action Team has gathered information to help employees guard against coronavirus-related scams, which are unfortunately emerging on a regular basis. The company has established a “fraud alert page” where employees can receive up-to-date information.

Maintain open, honest communication

Skanska is utilizing its internal company website (intranet) to provide general updates on COVID-19. The intranet is also being used to reinforce guidelines and standard operating procedures, and this same information is also available through the company’s mobile app.

As reported by the Cincinnati Business Courier, telling employees to stay home when they are not feeling well is a critical piece to maintaining a safe, functioning workplace. To reinforce the importance of this policy, HGC Groups, a large regional general contractor based in Cincinnati, has temporarily stopped recording unscheduled absences. In other words, an employee who thinks they may have COVID-19 symptoms will not be penalized for calling in sick to work.

Life has changed, but still goes on

In Orlando, Florida, work on a $2.15 billion airport project continues amidst the COVID-19 crisis. As reported by the Orlando Business Journal, several guidelines have been put into place so work can continue:

  • Employees showing signs of illness are sent home?
  • Additional handwashing stations have been made available
  • More frequent cleaning of high touch point areas like stairwells
  • Administrative staffs are evaluated for possible shift adjustments to limit personal interaction

The economic toll of COVID-19 has already set in. That said, some financial analysts expect that industries like manufacturing and construction will be among the last to begin issuing layoffs, due to the significant shortage of skilled workers these industries have been experiencing. Construction firms are expected to take proactive measures to help protect their workers and ongoing projects.


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