Experiment 3 - Bend Test of Reinforcing Steel Bars

Mapúa Institute of Technology Technology School of Mechanical and Manufacturing Engineering

ME136P – A1 Experient no! 3 "E#$ TEST %& 'EI#&%'(I#) STEE* "A'S

 #ae+ Ma,ago- .aya Mae T!

$ate Perfored+ 1/060/12

Student no!+ /11/1/

$ate Su4itted+ 110/0/12

Engr! .eroe *opena Instructor 

%".E(TI5ES+ a! To deterine the ultiate strength of the reinforcing steel 4ars hen su47ected to 4ending load!  4! To exaine the reinforcing steel 4ars physical conditions!

I#T'%$8(TI%#+ "end testing is a ethod done using the 8ni9ersal Testing Machine to test one specien:s ductility ;1ero! A4o9e this neutral axis- here the side of the specien has direct contact ith the 4ending punch has copression forces- going to the center of the specien! "elo the neutral axis- coes the tension force- going outard- stretching the specien- ith the help of the fulcru rollers! After the 4end test- using the axiu force in the printed resultsand soe physical inforation of the specien- e are a4le to copute for the flexural strength of the steel 4ars! ?e are then a4le to classify the to their physical conditions! *IST %& APPA'AT8S+ • • • • • • •

Shiad>u 8ni9ersal Testing Machine 8@A( Series &lexure4ending ta4le apparatus &lexure4ending punch Speed (utter  Steel tapes and (aliper  ?eighing Scale MarBing $e9ice C(enter punch or dran ith inBD

P'%(E$8'ES+

1! Prepare one plain steel 4ar and one defored steel 4ar specien! See &ig!;1
! $eterine the eight

of each

&igure 

specien! Shon in &ig!;3
&igure 3

3! Measure the noinal diaeter of each specien! See &ig!;
Cross − sectional Area =

! space

πd

2

4

$eterine

a9erage lugsthe a9erage height of lugs- and the suation of gaps- for the defored steel 4ar specien! See &ig!;2
of

the

&igure 2

2! Perfor 4end test using the 8ni9ersal Testing Machine! ?ait until the flexure 4ending punch  push don the steel 4ar through the fulcru rollers! See &ig!;6
&igure 6

6!

Exaine the 4ent specien- and checB for cracBs along the steel 4ar! (lassify its physical condition- hether it has cracBs or none! Add rearBs- hether the steel 4ar specien is g ood or 4ad!

! (oplete the other necessary inforation in the data sheet! $eterine the diaeter of the flexure 4ending punch! See &ig!;
F! The 9alues for the 4ending load can 4e gathered at the printed results of the 8TM!

G! (opute for the 4ending stress or the flexural strength of the steel 4ar! 8sing the forula+

 F max x L S f 

4 =

πD

 x

D 2

4

64

1/! $eterine the degree of 4end of the steel 4ar!

$IS(8SSI%#+ In this experient- e are focused on deterining the ultiate strength or the flexural strength of the reinforcing steel 4ars hen su47ected to 4ending load! This is done using one plain steel  4ar and one defored steel 4ar! Theses speciens are placed on the fulcru rollers of the 8TM! The flexure 4ending punch sloly pushes don the idline of the steel 4ars- to an extent that it  passes through the fulcru rollers! The axiu force is then printed out- and the flexural strength of each steel 4ar is coputed! Each specien after the 4end test is also checBed for  cracBs- and the physical condition is recorded on the data sheet!

(%#(*8SI%#+ The 4end testing of 4oth plain steel 4ar and defored steel 4ar pro9ided us ith results that the  plain steel 4ar can 4e su47ected into a higher 4ending load than defored steel 4ar! The coputed flexural strength of the plain steel 4ar is also higher than of defored! Although- 4oth speciens differ in the aount of 4ending load and 4ending stress they can 4e su47ected to- they  4oth ended up ithout cracBs along the 4ent portion- resulting to good rearBs!