INNOVATIVE TEST METHOD FOR MEASURING THE PERMEABILITY OF CONCRETE

Permeability plays a significant role in the durability of concrete structures as it controls the rate at which moisture is introduced into the concrete. This property may be measured by determining the rate of flow through a concrete specimen. For example; AASHTO T 259 “Method of Test for Resistance of Concrete to Chloride Ion Penetration and AASHTO T 277 “Standard Method of Test for Rapid Determination of the Chloride Permeability of Concrete”. However, these tests require a great deal of preparation and require a certain level of training and can take years to obtain adequate results. In addition, the use of mineral admixtures has been speculated by researchers to produce false results in the rapid chloride penetration test (AASHTO T 277). There exists a need for a straightforward permeability test that requires little preparation and produces accurate results. This paper outlines work carried out to develop a new test method which can accurately measure the absorption capacity of concrete with excellent repeatability. This innovative testing procedure measures the volume of water that is absorbed by a concrete specimen within a three to six hour period of time. The Laboratory Concrete Permeability Device (LCPD) measures water displacement accurately to 10 mL. The absorption capacity of the concrete specimen is measured by placing the sample in water and measuring displacement over a period of time. The total surface area of the sample is calculated to determine the absorption per surface area. The measuring system uses proprietary sensor connection technology to measure small pressure changes. Samples are being tested with water-tocementitious material ratios (w/cm) ranging from 0.26 to 0.60 and various amounts of mineral admixtures.

• INTRODUCTION

• RESEARCH SIGNIFICANCE

• BACKGROUND

• EXPERIMENTAL STUDY

• INTERPRETATION OF RESULTS

• CONCLUSIONS

• REFERENCES