compatibility of ultra high performance concrete as repair material

3.5 Roughness measurementTwo methods were used to evaluate the degree of roughness obtained by each surfacetreatment: the macrotexture depth test and the Concrete Surface Preparation index (CSP)given by ICRI guide (International Concrete Repair Institute 1997). Figure 3.12 showsboth roughness tests.(a) Sample macro texture depth of concretebeams(b) Concrete Surface Preparation indexFigure 3.12 Tests to measure the degree of roughness of the concrete substrateThe macrotexture depth, according to ASTM E965-96 “Standard Test Method forMeasuring Pavement Macotexture Depth Using a Volumetric Technique” determines thearea covered by a known volume of glass spheres spread on the concrete surface. Thevolume of the glass beads used in the test was 2 ml, although the minimum valuespecified is 25 ml, due to the size of the samples were not large enough. The testapparatus consists of a known volume of glass beads, a flat rubber disk for spreading thebeads on the surface, and a ruler for determining the area covered by the glass beads. Forthat, four different measurements of the diameter were taken. The test was repeated fourtimes over different surfaces locations of each concrete specimen. The Equation 3.3 wasused in order to determine the average macro texture depth from the measured diameters.MTD = 4 ∗ VD 2 ∗ πEquation 3.3where MTD is the mean texture depth of macro texture (in), V is the sample volume (in 3 ),D is the average diameter of the area covered by the glass beads. More information aboutthe macrotexture depth test can be found in the Appendixes. It should be noted that the57