LT$-12.$ As a continuation from Problem No$.$ LT$-11,$ there will be a group of thirty $12-$inch

O$.$D$.$ closed end steel pipe piles $($from Problem No$.$ LT$-11)$ that are to be installed with $36$ inches

center to center spacing between adjacent piles. Use the allowable load determined in Problem No$.$

LT$-11$ above or the allowable load determined for the total allowable load on this group of $30$ piles

to estimate clay consolidation settlement of the group under the total load.

The steel pipe pile will be $60ft$ long in medium stiff clay, with unit weight $=115pcf$ and

undrained shear strength $=1600psf.$ The steel piles will not be filled with concrete. The

groundwater table is $35ft$ below ground surface. There will be $30ft.$ of clay below the pile tips and

overlying bedrock. Clay OCR $=2\mathrm{.}5,Cr=0\mathrm{.}045,Cc=0\mathrm{.}18.$