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7/25/2019 addtl

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Compaction

Your frms lab manager tells you that the maximum dry density or the soil to be

used or fll on your project is 105.2 lbs/t at an !"# o 11$ according to %&'"

()*+. %t the site, you fnd that that frst lit o fll placed has a moist unit -eight o

11+. lbs/t at a -n o 12.1$. hat is the percent compaction or the frst lit s

this percent compaction een possible

d,feld 311+. lbs/t /3140.121 105.5 lbs/t 6 3$ 3105.5 lbs/t /105.2

lbs/t 7 100 100.$. Yes.

Stress

You hae been gien the results o a recent geotechnical exploration or a local

project in #helmsord, "%. 'he ground-ater table at the time o exploration -as 8 t

rom the existing ground surace. 'his is also the interace bet-een the and #9

soil layers. :igure # proides the soil profle at the time o geotechnical exploration.

:rom the proided inormation, calculate total stress, pore pressure, and e;ectie

stress -ith depth and plot them on the proided graphs. You must label numbers onthe graphs or ull credit.

#alculate total, pore pressure, and e;ectie stresses -ith depth at the

ollo-ing points sho-n in :igure #ottom o 9ayer and ?' location 38t belo- existing ground

surace

=oint >< "iddle o #9 layer 3not needed or this exam, but -ill be helpul later

=oint #< >ottom o #9 9ayer 310 t belo- existing ground surace

=oint (< >ottom o ?ien &oil =rofle 320 t belo- existing ground surace

=oint % -3t 3)2.8 pc3t 1+B ps

A> > C u> +20 ps C 1+B ps ) ps )5 ps

3rounded

=oint # 4 &%',#93t +20 ps 4 3120 pc3t 11+0 ps

@# -3)t 3)2.8 pc3)t B8 ps

A# # C u# 11+0 ps C B8 ps +0) ps +05 ps

3rounded

=oint (