Performance of externally bonded GFRP sheets on concrete in tropical environments. Part II: Microstructural tests

In the first part of the paper the structural scale tests on the synergistic effects of moisture, temperature, alkalinity and stress level on the performance and durability of GFRP sheet bonded externally on concrete have been discussed. This part describes the microstructural studies to find out the nature, quantum and mechanism of deterioration in the conditioned sheets. Micrographic investigations were carried out using a scanning electron microscope (SEM) to visualize the changes in the microstructure. The other tests are energy dispersive X-ray analysis (EDX) and inductively coupled plasma mass spectrometry (ICP-MS) to determine the chemical changes in the composite.