Laserfiche WebLink
Chapter 7:Hazard Analysis—Earthquakes <br /> Other areas experience small deformations (less than 2 inches) and more minor damage. <br /> Piers 2, 2A and mooring dolphins which are 1960's and 1990's era structures experienced <br /> only minor cracking or spalling and remain in service. Terminal yard pavements experienced <br /> settlement and cracking damage. Terminal shipping warehouses, the harbor masters office <br /> and grain silage building also experienced racking, masonry cracking and minor cladding <br /> damage. The fuel tank farm and cement silo experienced only minor cracking. Several <br /> electrical and water utilities were broken. The cement and grouted rip rap storm drainage <br /> channel also experienced minor cracking displacements,but remained serviceable. <br /> Elevation <br /> (k) <br /> -3D <br /> 20 <br /> Dense Fill <br /> ao Pier 1(typ) <br /> _ <br /> M L.L.W. Loose to Dense Loose Al — <br /> Natural Coral <br /> 10 Sand and Gravel Original Gro und Dredged Harbor Bottom <br /> 20 <br /> 30 Dense Natural Coral Sand&Gravel <br /> aD — Variable Basalt Formation <br /> so — — — — — — _ 10%Slope — <br /> o Hard(fresh)Basalt l — — — — — — — _ — <br /> Figure 7-9. Interpreted subsurface profile of Pier 1 <br /> Site Response Study <br /> The subsurface geology of Kawaihae Harbor (i.e., loose coral deposits) is significantly <br /> different than geologies of the strong motion sites that recorded the Kiholo Bay earthquake, <br /> which are located on volcanic soil, ash, or rock. Estimate of surface ground motions at <br /> Kawaihae was between 0.3 and 0.6g, A site response analysis was performed based on an <br /> average shear wave velocity(Vs)profile. A total of nine Spectral-Analysis-of-Surface Waves <br /> (SASW) surveys lines were surveyed at Kawaihae Harbor. The results of the SASW surveys <br /> indicate fill and soil thickness of 40 to 90 ft over basalt. Low blow count SPT data in the <br /> coralline soils and observed liquefaction confirm that the upper 30 to 50 ft is code site class <br /> F. <br /> Liquefaction Studies <br /> Liquefaction is a soil behavior phenomenon where shear strength loss occurs due to the rapid <br /> build-up of excess pore-water pressure, which reduces effective stresses in the soil to zero. It <br /> is most commonly generated by strong earthquake ground shaking. In general, soils most <br /> susceptible to liquefaction are loose, saturated, uniformly graded sands containing little or no <br /> fines, such as dredged fills used to construct reclaimed landside areas of the harbor. <br /> Evidence of liquefaction was observed extensively at Kawaihae Harbor in the vicinity of Pier <br /> 1 and 2, in pavement areas at the pier structures, in the terminal yard area and within the <br /> waterfront storage warehouses. Sand boil emissions occurred through cracks in pavements, <br /> with associated settlements up to 7 inches, including shallow footings. Lateral displacements <br /> 7-10 Hawaii County Multi-Hazard Mitigation Plan <br />