Highway Research Record

VI. RESEARCH WORK DONE IN ACADEMIC INSTITUTIONS RELATED TO THESIS WORK
B. PAVEMENT ENGINEERING AND PAVING MATERIALS
Behaviour of Self Compacting Concrete Pavements

Date of Start:July 2004
Civil Engineering Department, Indian Institute of Technology, Roorkee (R, I)

Scope and Objectives
The present study was undertaken with the following objectives:
(i) To prepare mix design for M45 and M55 grades of SCC.
(ii) To study various parameters like strength (Flexural and Compressive), modulus of elasticity and Poisson’s ratio
(iii) To know the behaviours of SCC in Pavement at various locations.

Methodology
A number of procedures for designing SCC mixtures have been proposed. These can be broadly classified into four categories.
a) Empirical methods
b) Rheology based methods
c) Particle packing models
d) Statistical methods

In the present thesis, empirical method given by Okamura and Ozawa for the mix-design of SCC was followed. The trial proportions of SCC mixtures were determined on the following basis:
(i) Coarse aggregate content not to exceed 50 percent of solid volume.
(ii) Sand content on volume basis not to exceed 40 percent of mortar volume.
(iii) A water-powder ratio, on a volume basis, of 0.9 to 1.0 depending on the properties of the powder.
(iv) Water-content and superplasticiser dosage to be determined to ensure self compactability.

Findings and Conclusions
(i) It has been verified by using the slump flow and u-tube tests, that self compacting concrete achieved consistency and      self-   compatibility under its own weight without any external vibration of compaction. Also because of the special      admixtures used, self-compacting concrete has achieved a density between 2400 and 2500 kg/m3, which were greater      than that of normal concrete.
(ii) The surface finish produced by self-compacting concrete is exceptionally good and patching will not be necessary.
(iii) The self-compacting concrete mix had a higher cementious content and contained fly ash when compared to standard       concrete mix.
(iv) From the static tests, the ultimate load carrying capacity of a 100 mm thick SCC slab at the Centre, Edge and Corner       regions were found to be 196.20 kN, 127.53 kN and 107.91 kN for mix M1 (cement 400 kg/m3, fly ash 160 kg/m3) and       235.44 kN, 147.15 kN and 127.53 kN for mix M2 (cement 440 kg/m3, fly ash 132 kg/m3) respectively. The theoretical       values by IRC method are 155.28 kN, 95.114 kN and 90.392kN for mix M1 174.49 kN, 107.89 kN and 101.25 kN for mix       M2. Thus, SCC pavement is proved to be a better alternative for the design of future roads with high intensities of traffic.