Damage sensing, mechanical and interfacial properties of resins suitable for new CFRP rope for elevator applications

The evaluation of damage sensing for flexural, interfacial and fatigue conditions was studied for carbon fiber reinforces plastic (CFRP) rope, with 4 different formulations of epoxy resin. Thermal analysis and tensile tests were used to investigate the thermal and mechanical properties for different epoxy formulations. Using these experimental results along with the empirical equation between tensile strength, glass transition temperature, Tg, and enthalpy, ΔH, optimum conditions for the epoxy formulations were found. Eddy current and static contact angle measurements were made to evaluate the wettability of epoxy into the carbon fibers with the different epoxy types. Flexural strength, fatigue strength and inter-laminar shear strength (ILSS) were evaluated for manufactured CFRP rope via pultrusion process. Changed ratio of electrical resistance (ER) of CFRP rope were measure during flexural testing, for signs of micro-cracking leading up to final fracture. The signal of CFRP rope were measured by changes in electrical resistance (ER) to predict the fracture failure. From the results of these studies it was concluded that an acid anhydride-based epoxy was the optimal epoxy formulation for manufacture of CFRP rope.