S - Kam Ng PhD Dissertation Final.pdf - Digital Repository of CCEE ...

̇̇̇̇51= pile bottom velocity at previous time j-1, m/s or ft/s, and∆t = computational time increment, s.With this new radiation damping model shown in Figure 2.10, the relative displacement andvelocity between pile and the support soil mass at any pile segment can be computed usingthe Eqs. (2.27) and (2.28), respectively. These two equations are written for all shaftsegments; however, the M s and C sk can be replaced with M t and C BT for the toe calculation.The pile segment i and soil segment k at time counter j are selected for a generalization.[ ( ̇ ) ] (2.27)̇ ̇ ̇( ̇ ̇ ). /(2.28)where,u riu iu ss,i,j-1= relative displacement between pile segment i and its soil mass, m or ft,= pile displacement at segment i, m or ft,= soil mass displacement at time j-1 and pile segment i, m or ft,= soil mass velocity at time j-1 and pile segment i, m/s or ft/s,∆t = computational time increment, s,R kC vkC skM s= relative velocity between pile and support soil mass, m/s or ft/s,= pile velocity at segment i, m/s or ft/s,= total soil resistance force at soil segment k, kN or kip,= linear viscous damping coefficient at soil segment k, kN-s/m or kip-s/ft,= radiation damping coefficient at soil segment k, kN-s/m or kip-s/ft, and= support soil mass at soil shaft segment k, kN-s 2 /m or kip-s 2 /ft.2.4.4. CAPWAP signal matchingThe main objective of CAPWAP analysis is to achieve the best signal matchingbetween the computed and measured signals through the simultaneous adjustments of pilemodel and soil model. In CAPWAP, the quality of the signal matching is measured in terms