The key to good concrete is durability. If you can keep the moisture from freely traveling through the concrete, you have solved many of the age-old problems associated with concrete. High Performance Normal Strength Concrete means concrete with a high strength and a low permeability the two properties are linked because high strength requires a low volume of pores, especially the larger capillary pores. The concrete is very dense since it has a minimum volume of capillary pores and these pores became segmented during curing.

Over 40 mix designs were studied before selecting the final mix design. This intensive experimental study has already cast over 850 specimens for evaluation. The preliminary study will run for one year and subsequently run two to three additional years. The tests incorporated the determination of compressive, splitting tensile and flexural strengths, modulus of elasticity, creep and shrinkage, chloride penetration and petrographic analysis at 7, 14, 28 days, 3, 6 months and one year time intervals.

In the first 180 days of the testing the MWC High Performance Concrete has been reported to yield higher quality concrete at a fraction of the usual cost, quicker and easier placement, which reduces finishing time, generates less shrinkage and cracking, stronger bond of concrete to steel and increased compressive strength. A one-time permanent application of CDS has been reported to significantly densify concrete (making concrete virtually impermeable), improving thermal resistance, increasing strength and lowering creep deformation potential.

The application of MWC and CDS enhances the durability of concrete at a fraction of the cost of other pozzolanic materials. This study encompasses the determination of the mechanical properties, petrographic analysis, detection of concrete deterioration and steel corrosion due to chloride penetration, creep and shrinkage of a variety of samples of High Performance Concrete.

The durability, of concrete depends largely on its ability to resist the penetration of water and aggressive solutions. The test results to date show that the workability of MWC High Performance Concrete is greatly enhanced through increased lubricity, resulting in a better surface finish and improved aesthetic appearance. Neither bleeding nor segregation was observed in any of the mixes containing MWC. MWC also reduced plastic separation and improved abrasion resistance.

The mechanical properties of compressive, splitting tensile, flexural strength and modulus of elasticity results were all higher than the excellent control specimens in both the normal and severe environments throughout the 180 period covered by this report. Because CDS seals the moisture within the specimen and does not allow the intrusion of moisture in or out of the specimen the initial lower strength of the CDS specimens increased as the specimens age.

The chloride penetration in the saline environment in specimens with MWC was appreciably lower than those specimens without MWC.

The result for the air-void content between the MWC specimens and the control specimens is about 50% with MWC providing fewer voids, greater density and less permeability.