The Michigan Department of Transportation (MDOT) spent $75 million to replace 88 lane miles of pavement on I-275 through Wayne and Oakland Counties, in Metro Detroit, Michigan. This particular stretch of I-275 is the busiest stretch of freeway in MI. Therefore, MDOT instituted a $150,000/day penalty if the freeway was not open September 1, 2016. MDOT also specified slag cement for its superior durability and alkali silica reaction (ASR) mitigating properties, to name a few. Since the work started the last week of May, 2016, Toebe Construction, LLC (Toebe) chose to utilize LafargeHolcim (LH) MaxCem, a Type IS (30) [ASTM C 595 blended cement]. Since the paving totaled 200,000 cubic yards (yd3) of concrete, Toebe knew that utilizing slag cement as a blended product would work best, logistically, to meet the demands of the tight schedule, avoid penalties, and deliver the best pavement.
MDOT specified 30% slag cement for its exceptional characteristics including increased durability, ASR mitigating properties, and its ability to stabilize the cement paste to create a more robust environment for the development of air entrainment. The slag cement was utilized as a component in an ASTM C 595 blended cement [LafargeHolcim MaxCem, a Type IS (30)] to best meet the logistics of this very fast tracked project.
This stretch of I-275 was totally reconstructed and paved just 15 years ago. This previous pavement did not include slag cement and the pavement failed due to ASR and a poor air void system. MDOT specified the 30% slag cement for its hardened concrete characteristics such as increased durability, and ASR mitigating properties. MDOT is also of the opinion that slag cement helps aid in creating a more stable paste for the proper development of air entrainment. Toebe, who likes slag cement for its rheological properties, appreciates its added creaminess and its ability to hold a nice edge as the paver moves through the plastic concrete. Therefore, the slag cement was instrumental in delivering the best pavement to MDOT and motorists.
An innovative aspect of the I-275 project is that the slag cement is blended separately with Type I at the LafargeHolcim terminal in Detroit, MI. The terminal stores individual cements and cementitious products and blends them together on demand and into the customer’s waiting truck as an ASTM C 595 blended cement. Since Toebe knew that the 200,000 yd3 of concrete needed to be placed in a rather short time, utilizing one blended cement as opposed to trying to manage two cements made their job easier and helped deliver a terrific job and avoiding costly penalties.
Project credits: Michigan Department of Transportation, Owner, Engineer; Toebe Construction, LLC, Contractor, Concrete; LafargeHolcim, Slag Cement