Abstract: Jinsha River Bridge located at the XiangLi highway is across the Tiger Leap Gorge deep canyons. The topography condition and geologic structure as well as the formation lithology are very complicated. In addition, the topography and weathering zone as well as the unloading belts on both sides of the bridge site are unsymmetrically developed with unfavorable geological conditions. The complicated geological conditions result in the extreme difficulties for the bridge site selections. Filtering the key geological factors from various potential affecting factors is critical to the bridge site screening. Results from the comprehensive exploration program indicate that the key factor is the tectonic structure. It is related to the topography, stratigraphy and lithology, adverse geological conditions, geological structures at both banks, weathering zones and unloading belt.

Key words: Tectonic Structures, Tiger Leap Gorge, Jinsha River Bridge, Bridge Location Selections, Geologic Conditions Comparison