INFLUENCE OF SILICA FUME ON THE AGGREGATE / MORTAR INTERFACIAL BOND STRENGTH

The strength of the interface between three types of cylindrical aggregate (sandstone, limestone, granite) and two types of mortar matrix (plain and 20 % Silica Fume (SF) mortar) was obtained experimentally by means of aggregate push-out. The relative interfacial thickness of the interface was determined by using scanning electron microscopy (SEM) images. Interfacial strength was then related to the relative interfacial thickness. It was found that 20 % SF replacement of cement and the use of superplasticiser (SP) resulted in thinner interface and higher interfacial bond strength as a result of densified microstructure. The interfacial bond strength was found to increase as the aggregate size reduces, irrespective of the type of aggregate and mortar matrix. This size effect is shown to be statistical in nature and described by Weibull theory

• INTRODUCTION

• EXPERIMENTAL DETAILS

• PREPARATION OF SPECIMENS

• DETERMINATION OF RELATIVE INTERFACIAL THICKNESS

• EXPERIMENTAL METHOD FOR AGGREGATE PUSH-OUT

• RESULTS AND DISCUSSION

• CONCLUSIONS

• ACKNOWLEDGEMENTS

• REFERENCES