Thailand Hill and Mountain Slope Analysis: Design and Testing Considerations

Slope segment gradients and lengths were field-measured in five widely scattered areas of Thailand. In each of these areas the lithology, geologic structure, climate, and vegetation differ considerably. The composite data include 2,798 slope segment lengths and their respective gradients from 157 traverses totaling 49.3 miles. There are no significant differences in the slope gradient frequency distributions of the five study areas. The composite slope segment gradient distributions is platykurtic from about 5 degrees to almost 30 degrees, and it is positive skewed. The platykurtic part of the curve is or - 1 percent of the 14.5 percent level of occurrence. The distribution has no suggestion that slope gradients have a tendency to concentrate in several polymodal ranges for soil covered slopes in the large heterogeneous physiographic provinces of Thailand.