DIC analysis of nano concrete using functionalized and dispersed carbon nanotubes

Abstract

Digital Image Correlation (DIC) method is considered as a powerful tool to capture material behavior for improved precision. This paper deals with effect of dispersion and functionalization of multiwall carbon nanotubes (MWCNTs) on fracture mechanics properties such as fracture energy and stress intensity factor. Fracture mechanics properties were found out using DIC technique and also by experimentally using a clip gauge and linear variable differential transformers (LVDT). The experiment was conducted under crack mouth opening displacement (CMOD) controlled manner and rate of loading was set as 0.0005 mm/s. MWCNTs were taken in a proportion of 0.1%, 0.2%, 0.3%, 0.4% and 0.5% by weight of cement and Nano silica and Nano alumina were considered as 3% and 2% by weight of cement respectively. The compressive strength is increased by 45.28% and tensile strength and flexural strength increased by108.26% and 53.249% respectively. It was seen that displacements measured by DIC and by experimentally were in the same line and also Load vs CMOD graphs plotted with both the methods are having similar behavior. Size effect was considered for preparation of all the specimens and by the results it can be seen that all specimens follow Bazant’s Size effect law.