Hunnu Concrete LLC, owned by Teso Properties, was established in 2011 with the purpose of manufacturing concrete mortar and providing high quality services on site with the best technology. Hunnu is one of the top concrete companies, winning “Best Quality Award” at Construction Expo and “Best Technology” from the Ministry of Construction.
The Project: Sky Garden Residence
In 2018 the Hunnu team started work on the Sky Garden Residence in Ulaanbaatar, Mongolia. The luxury large-scale residential community includes low, medium, and high-rise buildings and multiple community centers, including a garden. One of the primary design features of each building floor is the 3.6-metre-tall windows for maximum air flow.
During construction, Hunnu performed numerous mass concrete pours. One of the most important specifications for the project, given by the project engineer, was to keep the concrete slabs below 70 degrees Celsius to ensure continuous curing and strength development. This was especially important since Ulaanbaatar is the coldest capital in the world, meaning that construction projects have tight deadlines as temperatures can fluctuate rapidly. As a result, heating controls in Mongolia are very expensive.
The main problem Hunnu faced in this project was the consistent rise in temperature of the in-situ slabs which went up 5 degrees every half hour. This made it difficult for the team to maintain the temperature of the mass pours at 70 degrees Celsius. The team also found that their temperature information was not accurate when they were using mechanical wires for temperature tracking.
Another issue the team encountered was the accuracy of the method of strength testing. Cube testing is a requirement in Mongolia. The team was therefore only able to collect strength data when the specimen were broken on the 1st, 3rd, 7th, 14th and 28th days after a pour. Though these tests rarely came back under strength when lab-cured, field-cured cubes were frequently not reflective of the in-situ curing conditions. This limited their ability to accurately monitor the in-situ concrete strength of their slabs.
Wanting to improve their testing processes and provide their customers with the most innovative products on the market, the Hunnu team discovered Giatec and their SmartRock sensors at the World of Concrete expo in January 2018.
It was SmartRock’s ability to track concrete temperature and strength in real-time and share project data that convinced them to move forward with the sensors on the Sky Garden project.
Since the maturity method is not yet a standard in Mongolia, cube testing was still required on the project. The Hunnu team used their own lab for standard-cured cube testing. Maturity calibration for the sensors were provided by Giatec. The team used 45 sensors during construction, using one for every 50-100 m3 for a total of 3,000-4,000 m3 of concrete used.
With real-time temperature and strength monitoring Hunnu was able to accurately track all data. This meant that when temperatures continued to increase by 5 degrees they knew right away when to add cold water to the concrete to decrease temperatures. With the help of SmartRock, they were able to hold the temperature of the in-situ concrete at 70 degrees Celsius for the remainder of the project and ensured consistent curing and strength development.
Another huge benefit the Hunnu team experienced using SmartRock was the ability to easily share project data and critical information with all stakeholders.
“Each and all parties can trust each other as all activities are shared. This has helped us market Hunnu Concrete as trustworthy.”Hunnu Concrete LLC Contractor
As the first concrete company to use SmartRock in Mongolia, being able to provide this technology has been a significant differentiation point in the market for Hunnu. Hunnu wants SmartRock and the maturity method introduced as a national standard with the hope of eliminating field-cured cube testing and reducing their reliance on testing labs. The team plans to continue to use SmartRock on upcoming projects including the River Plaza Business Tower starting this November 2019.