2014
OAKLAND COUNTY, MI

The Problem

Deteriorating conditions including multiple distress symptoms were observed on sections of the I-96/I-275 corridor between approximately Kensington Road (exit 151) & Novi Road (exit 162). This is a segment of a main route used for travel between the Detroit and Lansing areas, and is one of the heaviest traveled roadways in Michigan. MDOT decided to replace the highly distressed pavement sections with full depth concrete repairs. 

During the repairs, any highway restrictions, including extended lane closures, would create potential for massive traffic congestion posing safety concerns for the driving public and also have a financial impact on the area. This project occurred concurrently with the I-96 fix, a separate nearby project in which a section of I-96 was completely closed, thus creating additional pressures for limiting lane closures. 

To minimize the negative impact on traffic, all repairs were required to be completed during night hours and the road had to re-open to traffic within 5 hours of placement. Typical concrete roadway patching mixes have not performed well due to the severe Michigan winters. 

The Sika Solution

The concrete requirements included achieving high early strength to ensure the roadway could re-open on time. Michigan DOT and the University of Michigan conducted a study and concluded that concrete patching mixes using Sika® Rapid-1 outperformed other current conventional patching mixes. Typically, roadways repaired using this mix design with Sika® Rapid-1 can be opened to traffic within 5 hours versus 12 to 24 hours for other patching mixes. As a result, Sika® Rapid-1 is now specified by Michigan DOT 

Sika® Rapid-1

Sika® Rapid-1

Strength/Hardening Accelerating Admixture

High Early Strength Concrete: Sika® Rapid-1 delivers excellent results in normal and
hot weather conditions where very high early strengths are required.  
  • Benefits
    • Early stripping and re-use of forms.
    • Faster finishing operations on flatwork surfaces.
    • Earlier post-tensioning.
    • Effective with Type I/II/III cements.   
    • Enhanced concrete sustainability through cement reduction and lower carbon footprint (eCO2).
  Precast Concrete: Sika® Rapid-1 delivers excellent results for precast concrete when high early strengths are required. Curing times are significantly reduced while concrete quality is improved.   
  • Benefits
    • Use as a replacement for steam curing to save energy costs.
    • Increase early strengths and allow faster rotation of molds to increase production per day.
    • Use as a replacement for Type III cement.
    • Enhanced concrete sustainability through cement reduction and lower carbon footprint (eCO2).
  Cold weather concreting: Sika® Rapid-1 is an effective hardening accelerator where high early strength concrete is desired and the use of calcium chloride is prohibited.   
  • Benefits
    • Insulation and heating costs for curing time can be reduced.
    • Earlier stripping and reuse of forms increases labor productivity.
    • Accelerated strength gain allows earlier structural use and speeds completion time.
    • Enhanced concrete sustainability through cement reduction and lower carbon footprint (eCO2).  
   Sika® Rapid-1 does not contain calcium chloride or any other intentionally added chlorides and will not initiate or promote the corrosion of reinforcing steel present in the concrete.   Placing concrete in freezing conditions: When used at Sika recommended dosage rates, Sika® Rapid-1 may reduce the need for cold weather concreting practices as specified in ACI 306-Standard Specification for Cold Weather Concreting. Field evaluations should be carried out when concrete is to be placed in freezing conditions to determine the minimum ambient and concrete temperatures required, and the optimum dosage for the desired setting time and strength performance. Sika strongly recommends that appropriate sound curing practices be used to protect fresh concrete from excessive heat loss in extreme weather conditions.

Benefits

Sika® Rapid-1 provides high early strength with minimal slump loss. This allowed for easy concrete placement and for minimal lane restrictions. The mix exhibited a high level of consistency with no rejected loads due to slump and/or air outside the specification. All lane re-openings occurred on time. 

Concrete Specifications
  Specification Requirement Average Results
Slump 7  ± 1" 6"
Air Content 5.5 - 8% 6%
Flexural Strength - 5 hours 300 psi in 5 hours 300-400 psi in 5 hours
Concrete Mix Design - LBS/CYD
Cement - Type 1 658
Coarse Aggregate 1770
Fine Aggregate 1380
Water 211
W/Cm 0.32
Sika Visocrete 2100 7 oz/cwt
Sika Rapid-1 25 oz/cwt
SikaSet NC 25 oz/cwt
Air Entrainer 0.6 oz/cwt