| Concept Diagram |
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| Method Overview |
- Supports earth pressure with a strut closely attached to the retaining wall
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- Resists earth pressure by supporting the strut on a support block
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- Installs a drilled anchor in the back and applies pre-stress to resist earth pressure through the frictional resistance of the anchorage
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- Resists earth pressure through the resistance of the helix blades connected to the wall after inserting helix piles in the back
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| Advantages |
- High stiffness of the strut
- No encroachment on adjacent land
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- Applicable when site space is wide
- Requires less bracing
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- Ample working space with minimal interference
- Economical for large excavation widths
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- Simple construction
- Ample working space with minimal interference
- Economical for large excavation widths
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| Disadvantages |
- Limited working space for excavation and structure work
- Vulnerable stability of the strut if span is extended
- Economically unfeasible for large excavation widths
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- Poor constructability of the structure
- The underground section of the structure is constructed in two phases, raising concerns about construction delays
- If the support block is unstable, it can cause significant displacement.
- Stability decreases with deeper excavation depths
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- Difficult to reinforce or repair
- Causes encroachment on adjacent land
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- Difficult to construct in soft and hard rock layers
- Increased need for access when necessary
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| Economic Feasibility |
100 (%) |
80 (%) |
90 (%) |
70 (%) |
Example of CIP Method Application
Helix Anchor Base Exploded View
