Transbay Transit Center Project Sh i W ll d E ti C t ti ...
Transcript of Transbay Transit Center Project Sh i W ll d E ti C t ti ...
Transbay Transit Center ProjectSh i W ll d E ti C t ti
301 Mission Buttress Shoring Wall and Excavation Construction
Structural Assessment
June 8 2010
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June 8, 2010
• Subsurface conditions and Transit Centre box
• Excavation process
• Movement analyses
• Movement monitoringMovement monitoring
• Summary
1852 Shoreline and Site ConditionsRelative to the DTX and the TerminalRelative to the DTX and the Terminal
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• Subsurface conditions and Transit Centre box
• Excavation process
• Movement analyses
• Movement monitoringMovement monitoring
• Summary
Construction of train box inside temporary braced shoring wall
40
20
0
Bracing C@ Depth 28ft
Bracing B@ Depth 16.5ft
Bracing A@ Depth 5.5ft
FILL
Bracing C@ Depth 28ft
Bracing B@ Depth 16.5ft
Bracing A@ Depth 5.5ft
Bracing C@ Depth 28ft
Bracing B@ Depth 16.5ft
Bracing A@ Depth 5.5ft
Typical SoilProfileCL-17 (3 ft) CL-18 (20 ft) CL-33 (40 ft)
43ft 43ft 43ft
80
60
40
Dep
th, f
t BAYMUD
43ft 43ft 43ft
-1 0 1 2
Cumulative Lateral
140
120
100
-1 0 1 2
Cumulative Lateral-1 0 1 2
Cumulative Lateral
COLMASAND
Exca
vatio
n
0 20 40 60Distance from Excavation, ft
CL-20 CL-21 CL-35 CL-36
CL-17 CL-18 CL-33 CL-34
SPTCWall
Line 23
Line 22
Displacement, in Displacement, in Displacement, in
MMTProject
BARTProject
1994j
1969/70
Photo courtesy of San Francisco Public Library
Soil-Cement Walls – Sequence of Installationq1) Mixing of First
Primary Panel
2) Mixing of Second Primary Panel
3) Mixing of Secondary Panel Between TwoPanel Between Two Primary Panels
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Typical Diagonal Bracing of Deep ExcavationsGap Building and EBMUD Wet Weather BuildingGap Building and EBMUD Wet Weather Building
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• Subsurface conditions and Transit Centre box
• Excavation process
• Movement analyses
• Movement monitoringMovement monitoring
• Summary
• Subsurface conditions and Transit Centre box
• Excavation process
• Movement analyses
• Movement monitoringMovement monitoring
• Summary
Monitoring ground movements
Extensometer Real time extensometer & inclinometer installationte so ete
Inclinometers and extensometers(sub surfacedisplacements).
Can be real time or manualInclinometer (x, y, 0.002 in/ft)Extensometer (z, +/- 0.01 inch)
Inclinometer and logging deviceInclinometer and logging device
Summary
•Established ground and groundwater conditionsS f l t t bilit t i l f h i ll•Successful constructability trials of shoring walls
•Excavation processes identified•Calibrated soil models using numerical analysis g ymethods•Predicted ground movements•General ground and water movement controlsGeneral ground and water movement controls established for general conditions•Shoring wall package is ready for market.