2.Open Excavation General Construction Sequence of Surface Tunnelling ■ Construction of retaining walls along the future underground structure (in competent ground, retaining walls may not be necessary) ■ Ground excavation and support of the retaining walls,if needed Completing the underground structure In case of cut-and-cover,reestablishment of the surface use 百年同海12
12 2. Open Excavation
2.Open Excavation Open Mine-Pits 百年同濟13 TONGII UNIVERSITY
Open Mine 13 -Pits 2. Open Excavation
2.Open Excavation Hydrofraise basic operation Guide Frame、 Inclinometer Mud to the Mud Pump desanding plant Rotary drum cutters Mud return into the trench after treatment 百年同海14 TONGILUNIVERSITY
14 Hydrofraise basic operation Rotary drum cutters Mud Pump Inclinometer Guide Frame Mud to the desanding plant Mud return into the trench after treatment 2. Open Excavation
2.Open Excavation Excavation 1st Bite 百年同濟15 TONGIUNIVERSΠTY
15 Excavation 1st Bite 2. Open Excavation
2.Open Excavation Excavation 2nd Bite 百年同海16 TONGILUNIVERSITY
16 Excavation 2nd Bite 2. Open Excavation