201 E MARINE VIEW DR 2016-01-01 MF Import

P.U.D. No. I of Snohomist�County June 22, 1994 Page 2 The piles were planned to extend to an elevation of approximately -14 feet. The driving was ternunated at a depth of approximately 22 eet (e,evation-8') because of the followin¢ reasons: 1) bearing capacity had been achieved or exceeded within that distance as evaluated by the ENR formu!a fcr the hammer used as shown on the attached Figure "Safe Pile Load", 2) the refusal c:iteria recommended in t6e geotechnical report had been exceeded (after conversion for fhe lazger hammer), and 3) to prevent damage to the piles by overdriving. • During the driven dmber pile installation, we observed that the timber piles were installed in general accoidance with the recommendations pre�ented in the geotechnical report and specificatioas. During driving, continuous records of the blows required to dnve the piles were recoried and the piles were obse:=.�ed for splitting or mushrooming. One pile split at the tip when driven initially. The split pile was removed, two feet was cut off of the tip, and the pile was rebanded before b�:ing redri�•en. As specified in Volume 2 of the Public Works Contract No. 93-778 (Geotechnical Report), Page 10, the piles were driven to refusal, defined as three blows per inch using a � driver with a minimum energy ra6ng of 10,000 ft-Ibs. Because the piles were actually ; driven with a 15,000 ft-lbs hammer this criteria was reduced to 0.5 blows per inch or 6 blows per foot. All of the piles were driven a minimum of 2'? feet and with a minimum of 13 blows per foot. According to the Engineering News Formula the pile capacity at 13 , blows per foot is 14.7 tons. The design capacity for these piles is 5.5 tons. A copy of the piling plan, pile driving summary, pile driving records, pile driving equipment data, and safe pile load graph (Engineering News Formula) are attached for your review. PEFHLV 3I•139(6f27/9a)1350.03/4 ��