Engineering Geological Assessment of Diversion Tunnel of Bakhtiari Damsite (Biggest Two-Arch Concrete Dam in Southern Iran)
Table 1
Name, symbol, and other details of formations that are available in the dam water diversion tunnels.
Formation length in the upper tunnel during excavation (m)
Formation characteristics
Parameter
78
Marly limestone (gray color if fresh or moderately weathered) with intercalations of marls and shales. Thickness of marly limestone layers varies from 0.15 to 0.4 m and shale layers change from 3 to 15 cm.
SV2
233
Alternating layers of dark gray marly limestone and siliceous limestone. Limestone layers have thickness between 10 to 30 cm, and siliceous limestone layers are 5 to 20 cm thick.
SV3
134
Is similar to part SV3 with a large number of discontinuities that leads to changes in some parameters.
SV3 (disturbed)
88
Medium to thick layered limestone of dark grey color, if fresh, and grey color if moderately weathered with small nodules of siliceous limestone including some chert and very thin intercalation of marl layers separate the limestone beds.
SV4
183
Thick to very thick gray nodular limestone with silica nodules and rarely made of chert
SV5
89
Medium to thickest dark gray limestone and marly limestone with intercalations.
SV6
105
Thin to medium thick of dark gray to black limestone and marly limestone layers (0.2 to 0.4 m) with thin marly intercalations. Thicknesses of these layers vary from 20 to 40 cm.
