Civil Engineering Materials (CEM) LAB REPORT
BY Abdulrahman Haruna Ibrahim (LCE!"#$%!"""&) E'ERCIE OE* ieve Anal+sis
AIM* This exercise was set out to determine the diferent sizes o aggregates. Aggregates o the same or almost the same sizes are trapped on sieve while smaller ones pass thru and go the next sieve.
TEP* Step 1 At the beginning o the exercise, aggregate sample is etched and cleared o dirt then 500g o it is taken. The 500g taken out o it is the sample or this sieve analsis. Also, the sieves are checked o trapped dirt.
Step 2 Then, ater the sieves are checked or dirt and cleaned the sieves are measured to get empt sieve weight beore the are arranged according to their permeabilit and then the are put on the shaker.
Step 3 Ater the sieves are put on the shaker, the aggregate sample is poured rom the top then the sieve shaker is turned on or about !"#0 minutes or the aggregates to ull settle into the right sieve.
Step 4 Ater !"#0 minutes the shaker is turned of and the sieves are removed careull rom the sieve shaker and the are taken awa or weighing with the sample in them. $ompare the sum o empt sieves and the sieves with samples in them. A variance o %&"'( is not acceptable.
Step 5 Then the table is made and all data is written there and also, the percentage o aggregate retained in each sieve. Ater that, ou calculate the percentage passing through the sieve. Ater the table is done a graph is to be plotted with the data obtained or aggregate size against percentage o aggregate passing.
Grading Curves The grading o aggregates afects the strength o concrete mainl indirectl, through its important efect on the water)cement ratio re*uired or speci+ed workabilit. A badl graded aggregate re*uires a higher water)cement ratio and hence results in a weaker concrete. using the grading chart, we will be able to see whether the grading o a sample conorms to that speci+ed.
A,,aratus -sed
Ab.ve are ,i/tures .0 the balan/e s/ale and sieves
A ,i/ture .0 the sha1er
Results and /.mments* At the end o the experiment the results were extracted and were used in a table as seen below. -or the total mass a total o gram was lost as a result o carelessness o some o the team members, which as a result gave us a total percentage o //.1 that2s a total loss o 0.1. 3 would want to believe b industr standards a 0.1 is acceptable.
Table ieve i2e
3eight .0 Em,t+ ieve (4ram)
3eight .0 ieve 5 am,le (4ram)
Mass Retain ed (4ram )
Cummula tive Mass Retained (4ram)
Cummula tive 6 Retained
6 Passi ng
#0
5/!
0#
4
4
0.
//.'
5
4//
5'
!
#.4
.
'.
5'
#4
'#0
4'
5
#.#
4/
/
#!
!.
'.4
0.
45'
45/
!
/0
!
''
0.
''
'4
'
/'
!.4
'#.
0.#5
/'
/4
'
/4
!.
'#.'
0.0!5
'
4
#0#
4/5
//
#
6an
#!
#!5
'
4/!
//.4
0.
/0
4'#4
4/!
"
E'ERCIE T3O CONCRETE MIX DESIGN
AIM This test is used all over the world to determine the consistenc o a resh concrete. 3t is utilized, as a method or watching that the right measure o water has been added to the mix.
te,s Step 1 Firstly 2.5kg of cement was measured on te !alance scale ten was poured into te mi"er
Step 2 5kg fine aggregate was poured into te mi"er# and ten 1$kg of coarse aggregate was added.
Step 3 %fter tat# 1.25 kg of water was added to te mi"ture# and ten te &i"er was turned on for a!out 5 minutes. For te second test 1.5 kg of water was added to te mi"ture.
Step 4 %fter te 5 minutes te !ottom gate of te mi"er was opened and wole concrete mi"ture is poured out.
%pparatus 'sed
Above are the apparatus used
EXERCISE THREE
Slump test AIM This test is used all over the world to determine the consistenc o a resh concrete. 3t is utilized, as a method or watching that the right measure o water has been added to the mix.
Steps Step 1 % slump mould# wic as a conical sape# is !rougt and filled up wit te concrete in 3 stages. 1st stage it is filled up 1(3 of te mould ten poked wit a metal rod 25 times# ten more concrete is added until it reaces te 2(3 of te mould ten it is poked. Finally it is completely filled up and te top is made flat ! y rolling te metal rod over te top of te cone. %fter# te area around e mould sould !e cleared and cleaned for accuracy.
Step 2 %fter a!out 1$ minutes of te previous step# te lifting of te cone is initiated via its side and les. )is lifting as to !e done wit e"treme ca ution so as not to damage te sape of te mould. *mmediately after te cone is lifted te slump would take its sape. *ts eiter is forms a true slump or sear slump or te wole concrete will collapse. +elow is a pictured e"ample on types of slump.
Step 3
Ater the concrete has taken its shape the height o the cone and the slump are recorded. The height o the slump is subtracted rom the height o the cone to get the workabilit o the concrete. elow is a guideline on the workabilit.
Description of workability and magnitude of slump: Description of workability
Slump (mm)
No slump Very low "ow #edium %ig& Very &ig&
0 5!0 !530 35$5 '0!55 !0 to collapse
A,,aratus -sed
Data: Slump )est
)est 1
)est 2
Slump
,5mm
11$mm
Sear
Sear
Slump )ype
*S+",S - ./##*N,S: s results s&ow from t&e two tests t&e workability of t&is slump is &ig& and also1 t&ey are bot& s&ear slumps2 ,&is implies t&at t&e bot& t&e mitures are slig&tly wet t&us causing t&e slump to s&ear2
E'ERCIE 7O-R COMPACTI4 7ACTOR TET AIM
This test uses the backwards approach7 the level o compaction accomplished b a standard measure o work is resolved. The thickness proportion measures the level o compaction, called the compacting actor, i.e. the proportion o the thickness reall attained in the test to the thickness o the cement completel compacted.
8teps 8tep# -ill up the bottom hopper and poked with steel rod. Ater +lling up weight the sample up and subtract the weight o the empt hopper rom the weight o the hopper & concrete. 8tep' The concrete sample is poured rom the top o the upper hopper gentl, and then the bottom door is opened do that the trapped concrete pours into the bottom hopper. 8ame procedure is done here onl that when the bottom door o the hopper is opened the mixture is poured into a clindrical container at the base. The top is cleaned using the rolling steel method. 8tep The thickness o the cement in the clinder is calculated and this thickness divided b the thickness o the completel compacted concrete is characterized as the compacting element. The recent thickness could be ac*uired b reall +lling the clinder with cement in our laers, each one packed or poked and ater that weighed. .ompacting factor
=
4eig&t of partially compacted concrete 3eight .0 0ull+ /.m,a/ted /.n/rete
8es/ri,ti.n .0 3.r1abilit+ and C.m,a/ting 7a/t.r 8es/ri,ti.n .0 9.r1abilit+ :er+ l.9
C.m,a/ting 0a/t.r ";<=
C.rres,.nding slum, (mm) "!>?
L.9
";=?
>?!?"
Medium
";&>
?"!%""
High
";&?
%""!%
A,,aratus -sed
Ab.ve are ,i/tures .0 a,,aratus used
Data: Compacting Factor )est
)est 1 -.31
)est 2 -.-
/eigt of partially compacted concrete
/eigt of fully compacted concrete
Compacting Factor
.,0,
.--
$.10
$.-0
*S+",S - ./##*N,S:
