Dynamic and Static Load Testing: A Cost Savings Approach-Paper

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The Ain Sukhna oil-jetty project in Egypt used a combined static and dynamic pile-testing program to establish safe, economical driving criteria for large-diameter open-ended steel piles across a highly variable seabed.<br /><br />Two test locations were evaluated. At each, compression and tension piles were dynamically tested during initial driving and restruck after short and longer intervals to measure time-dependent soil setup. Static compression and tension tests were also performed using a four-pile linear arrangement: two outer reaction piles and adjacent compression and tension test piles.<br /><br />Testing showed substantial capacity gains after installation. Shaft resistance increased by roughly a factor of five, with much of the gain occurring within the first ten days. Including end bearing, the overall resistance setup factor was about four. Dynamic and static test results were in good agreement, supporting use of dynamic testing to verify pile capacity and guide production driving. The tests also indicated that uplift resistance could be estimated at about 90% of compression resistance for the site soils.<br /><br />The results informed driving criteria that allowed piles to reach the required capacity with less embedment than initially planned. Average pile length was reduced from approximately 71–72 m to 62 m—about 9–10 m per pile. Across 400 piles, this saved roughly 3,600 m of piling and reduced driving effort. Shorter piles also enabled use of an additional jack-up barge, reduced stress and maintenance demands on pile templates, and shortened platform positioning time.<br /><br />The program therefore provided both a quality-control basis for construction and significant cost and schedule benefits, despite the project’s accelerated timeline.

Keywords

Ain Sukhna

oil jetty

pile testing

dynamic testing

static testing

steel piles

seabed

driving criteria

soil setup

compression tension piles