FEMA P55 Coastal Construction Manual, Fourth Edition - Mad Cad

Volume II DESIGNING THE FOUNDATION 10
Table 10‑9. Advantages and Special Considerations of Pile Installation Methods
Installation
Method
Driving
Augering
Jetting
• Well-suited for friction piles
COASTAL CONSTRUCTION MANUAL
Advantages Special Considerations
• Common construction practice
• Pile capacity can be determined
empirically
• Economical
• Minimal driving vibration to adjacent
structures
• Well-suited for end bearing
• Visual inspection of some soil stratum
possible
• Convenient for low headroom situations
• Easier to maintain column lines
• Minimal driving vibration to adjacent
structures
• Well-suited for end bearing piles
• Easier to maintain column lines
KHC = earth pressure compression coefficient
KHT = earth pressure tension coefficient
10.5.5 Scour and Erosion Effects on Pile Foundations
• Requires subsurface investigation
• May be difficult to reach terminating soil strata if
piles are only driven
• Difficult to maintain plumb during driving and
thus maintain column lines
• Requires subsurface investigation
• Not suitable for highly compressed material
• Disturbs soil adjacent to pile, thus reducing earth
pressure coefficients KHC and KHT to 40 percent
of that driven for piles
• Capacity must be determined by engineering
judgment or load test
• Requires subsurface investigation
• Disturbs soil adjacent to pile, thus reducing earth
pressure coefficients KHC and KHT to 40 percent
of that driven for piles
• Capacity must be determined by engineering
judgment or load test
Coastal homes are often exposed to scour and erosion, and because moving floodwaters cause both scour and
erosion, it is rare for an event to produce one and not the other. As Figure 10-6 illustrates, scour and erosion
have a cumulative effect on pile foundations. They both reduce piling embedment.
Figure 10‑6.
Scour and erosion effects on piling embedment
10-21