September 28th 2018
India could save sand by making concrete with plastic bottles
The Global Construction Review reported that researchers say India could alleviate its growing shortage of sand, which is needed for concrete, by partially replacing it with waste plastic.
A booming construction sector and rapid urbanisation has sent cost and demand for sand sky-rocketing, researchers said. This has led to unregulated sand extraction from riverbeds.
Researchers had to find a balance between the removal of sand and the addition of plastic. John Orr, the report’s principal researcher, said: “Typically, when you put an inert, man-made material like plastic into concrete, you lose a bit of strength because it doesn’t bond to the cement paste in the same way.
The research was published in the Construction and Building Materials journal.
Riverfront skyscraper ready to go vertical following massive concrete pour
Chicago Curbed reports that Downtown’s next office tower can begin its 54-story climb along the banks of the Chicago River following a carefully choreographed concrete pour early Saturday morning.
Starting before sunrise, crews from Clark Construction directed 3,300 cubic yards (more than 300 truckloads) of the gray stuff through the spindly arms of three mobile pumps to form the reinforced foundation mat of the building known as 110 N. Wacker.
The Goettsch-designed tower will feature a glassy facade and a publicly accessible riverwalk set behind angled columns along the building’s western side.
The plan also calls for a small pocket park along Randolph, ground floor retail, a soaring 45-foot-tall lobby, and 110 parking spaces concealed below Upper Wacker Drive.
Although the new office tower isn’t expected to open until 2020, construction fans can follow the action on the contractor’s overhead webcam.
UK study shows waste plastic can replace sand in concrete
The Engineer reported research from Bath University has demonstrated that some of the sand used in concrete can be swapped out for waste plastic, potentially leading to more sustainable construction.
Published in the journal Construction and Building Materials, the research explored the impact of five finely graded plastics on the structural strength of concrete tubes and cylinders. It was found that sand-sized PET particles from recycled plastic bottles provided the best results, achieving a target compressive strength of 54 MPa, similar to that of structural concrete.
The research recently received the Atlas Award for its potential societal impact around the world. While ground up waste plastic was used for the study, Orr told The Engineer that the team is now exploring some novel sources for plastic material that is already graded to the required level.
Wireless sensors in construction
Construction Canada reports that decision-makers in construction are hesitant to let go of traditional design, building, and testing methods. In a world where everything is becoming more connected and new systems are being developed for every facet of life, the use of smart technologies in construction is essential. More specifically, the use of sensors and devices for monitoring and assessing structural and material properties of concrete is essential.
Sensors and devices are being developed for a number of different applications on the jobsite. Some are designed strictly to monitor the properties of concrete during curing, while others are designed to track environmental conditions or project equipment.
For more information, take a look at Roxanne Pepin’s article