The objective of this work was to quantify weathering profile based on durability for heterogeneous siliclastic sedimentary rock. The current engineering geological weathering classification is qualitative which is less suitable for engineering purposes especially for heterogeneous sedimentary rock. In current work, modified-wetting-drying test were performed because no sample preparation is required. Recemented sandstone did not react or change when subjected to 3 cycles of modified-wetting-drying testing. Unlike the moderately to highly weathered shale, rock samples disintegrated from each cycle. The disintegrated samples from each cycle were sieved to determine the fragment size distribution. Different weathering grades showed different patterns of fragment size distribution for slightly weathered recemented sandstone, moderately weathered and highly weathered shale. © 2019 EAGE-GSM 2nd Asia Pacific Meeting on Near Surface Geoscience and Engineering.All right reserved.