Download - L3a Sieve Analysis
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The City College of New York Department of Civil EngineeringCE 345: Soil Mechanic!n tr"ctor: Dr# $eorge Mylonaki
LAB EXPERIMENT #3A:SIEVE ANALYSIS
$rain i%e analy i i a proce in which the proportion of material of each grain i%e pre ent in a given oil&grain i%e 'i tri("tion) i 'etermine'# The grain i%e 'i tri("tion of coar e*graine' oil i 'etermine''irectly (y sieve analysis + while that of fine*graine' oil i 'etermine' in'irectly (y hydrome er analysis #The grain i%e 'i tri("tion of mi,e' oil i 'etermine' (y !om"ined sieve and hydrome er analyses
The grain i%e analy i i pre ente' a a emilog plot of percent finer ver " particle i%e+ calle' a $rain
si%e dis ri"& ion !&rve # - emilog plot i " e' for the particle i%e to give (oth mall an' large 'iametera nearly e."al weight a po i(le# /ercent finer i alway plotte' a the or'inate " ing an arithmetic cale# 0rom the grain i%e 'i tri("tion c"rve+ grain i%e "ch a D12+ D32 an' D 2 can (e o(taine'# The D referto the i%e+ or apparent 'iameter+ of the oil particle an' the "( cript &12+ 32+ 2) 'enote the percent thati maller# 0or e,ample+ D12 2#1 mm mean that 12 percent of the ample grain are maller than 2#1mm# The D12 i%e i al o calle' the e''e! ive si%e of the oil#
-n in'ication of the prea' &or range) of particle i%e i given (y the !oe''i!ien o' &ni'ormi y () &*+which i 'efine' a
D 2) &
D12
The !oe''i!ien o' !&rva &re () !* i a mea "re of the hape of the c"rve (etween the D 2 an' D12 graini%e + an' i 'efine' a
&D32)) !
D 2 6 D12
No e: Yo" will plot the grain i%e 'i tri("tion c"rve an' calc"late ) & an' ) ! for com(ine' analy i &withthe re "lt of ieve an' hy'rometer analy i )#
In rod&! ion
- ieve analy i con i t of pa ing a ample thro"gh a et of ieve an' weighing the amo"nt of materialretaine' on each ieve# Sieve are con tr"cte' of wire creen with ."are opening of tan'ar' i%e # The
ieve analy i i performe' on material retaine' on an 7# S# Stan'ar' No# 22 ieve# Ta(le 1give a li t of the 7# S# Stan'ar' ieve n"m(er with their corre pon'ing i%e of opening #
Ta"le + , S Sieve N&m"ers and Asso!ia ed -.enin$ Si%es
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Sieve No pening Si%e &mm) Sieve No pening Si%e &mm)
/ 4#;5 30 2#5220 4#22 /1 2#4 5
2 3#35 /0 2#355#82 01 2#3224 #3 21 2# 52
+1 #22 1 2# 1+5 1#;2 41 2#182+/ 1#42 +11 2#152+2 1#18 +51 2#1 5+4 1#22 +/1 2#1251 2#85 511 2#2;550 2#;1 5 1 2#25331 2# 2 /11 2#238
A..ara &s
1# Sieve + a (ottom pan an' a cover
# - (alance en itive to 2#1g
3# Mortar an' r"((er pe tle
4# ven
5# Mechanical ieve haker
# /aint (r" h for cleaning ieve
;# Sample plitter or riffle
Pre.ara ion o' sam.le
The material to (e treate' i fir t air*'rie'+ after which the aggregate pre ent in the ample are thoro"ghly (roken "p with the finger or with the mortar an' pe tle# The pecimen to (e te te' ho"l' (e large eno"ghto (e repre entative of the oil in the fiel'# !t ho"l' al o (e mall eno"gh not to overloa' ieve #
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Ma,im"m particle i%e &cm) Minim"m weight of ample &g)
;#5 2225#2 4222
#5 222
1#2 12220iner than No# 4 ieve 220iner than No#12 ieve 122
Pro!ed&re
1# Collect a repre entative oven*'ry oil ample# Sample having large t particle of the i%e of No#4 ieve opening &4#;5 mm) ho"l' (e a(o"t 522 gram # 0or oil having large t particle of greater than 4#;5 mm+ larger weight are nee'e'#
# =reak the oil ample into in'ivi'"al particle " ing a mortar an' a r"((er*tippe' pe tle# &Note:
The i'ea i to (reak "p the oil into in'ivi'"al particle + not to (reak the particle them elve #)
3# Determine the ma of the ample within 2#1g & 6 )#
4# /repare a tack of ieve # - ieve with larger opening i place' a(ove a ieve with maller opening # The ieve at the (ottom ho"l' (e a No# 22# - (ottom pan ho"l' (e place' "n'er the
No# 22 ieve# The ieve that are generally " e' in a tack are No # 4+ 12+ 2+ 42+ 2+ 142 an'22> however+ more ieve can (e place' in (etween#
5# /o"r the oil prepare' in Step into the tack of ieve from the top#
# /lace the cover on the top of the tack of ieve #
;# ?"n the tack of ieve thro"gh a ieve haker for a(o"t 12 to 15 min"te #
8# Stop the ieve haker an' remove the tack of ieve #
9# @eigh the amo"nt of oil retaine' on each ieve an' the (ottom pan#
!f a con i'era(le amo"nt of oil with ilty an' clayey fraction i retaine' on the No# 22 ieve+ it ha to (ewa he'# @a hing i 'one (y taking the No# 22 ieve with the oil retaine' on it an' po"ring water thro"ghthe ieve from a tap in the la(oratory# @hen the water pa ing thro"gh the ieve i clean+ top the flow of water# Tran fer the oil retaine' on the ieve at the en' of wa hing to porcelain evaporating 'i h (y (ack wa hing# /"t it in the oven to 'ry to a con tant weight# Determine the ma of the 'ry oil retaine' on the
No# 22 ieve# The 'ifference (etween thi ma an' that retaine' on the No# 22 ieve 'etermine' in Step9 i the ma of oil that ha wa he' thro"gh#
)al!&la ion
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1# Calc"late the percent of soil retained on the nth ieve &co"nting from the top )
Ma retaine'+ 6 n R n AAAAAAAAAAAAAAAAAAAAAAA , 122
Total ma +6 & Step 3 )
# Calc"late the c"m"lative percent of oil retaine' on the nth ieve
n
R ni 1
3# Calc"late the c"m"lative percent pa ing thro"gh the nth ieve
n
percent finer 122 B R n i 1
No e : !f oil retaine' on No# 22 ieve i wa he'+ the 'ry "nit weight 'etermine' after wa hing &Step 12)ho"l' (e " e' to calc"late percent finer &than No# 22 ieve)# The weight lo t '"e to wa hing ho"l' (e
a''e' to the weight of the oil retaine' on the pan#
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7ATA S8EET: Sieve Analysis
De cription of oil: AAAAAAAAAAAAAAAAAAAAAAAA
Date: AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA