A proposed hexagonal control concrete specimen in lieu of other standard types
Dissertant
al-Saqi, Muhammad Mustafa Kamil
Thesis advisor
Sarsam, Qays Fuad
al-Ata, Tariq S.
University
University of Technology
Faculty
Building and Construction Department
University Country
Iraq
Degree
Master
Degree Date
2012
English Abstract
The strength of concrete is considered as the most basic and important material property in the design of reinforced concrete structures.
The two standard methods (ASTM and BS)for determining the compressive strength of concrete are the testing to failure of cylinder and cube specimens.
It has become a problem to use this value as the control specimen sizes and shapes are different from country to another.
This study is made to develop aspecimen thatincludes theease ofmakingacontrol specimen like a cube while avoidingthe capping process which is necessary in cylinders andreducingthe cost and time it takesto prepare.So thatthe proposedspecimenwill be achieveuserfriendliness, such as the cube.
At the same time the proposed specimen will lead to the same reliable results expectedfrom acylinderpreparedin an acceptable way.
The new specimen has a hexagonal cross sectional area.
The volume of the hexagonal specimen is approximately equal to the cylindrical onesto give a greater uniformity of results.
This proposed shape has height to average diameter ratio (H/D) = 1.95.
When it cast in horizontal plane so no need for end preparationbecausethe top and bottom surface of the specimen who will be in contact with platen of testing machine, are 100 % levelled and orthogonal to the height of the specimen.
Results show that the mean ratio of compressive strength for hexagonal to cylindrical specimen is 0.95 while it is 0.84 for hexagonal to cubic specimen.
In splitting tensile strength there are two dimensions, d1 the distance between two parallel faces and d2 the distance between two parallel corner tips in the specimen.
Results show that the mean ratio of splitting tensile strength when tested on d1 is 0.97 and 0.78 when tested on d2 compared to the standard cylindrical specimen.
Test results for specimen tested on d1 is more reliable than the results found from testing specimen on d2 When testing the hexagonal specimen according to ASTM C469 the mean ratio of Chord modulus of elasticity was 0.9 for hexagonalto cylindrical specimen and when the test performed using strain gauges the ratio of Young's modulus of elasticity at 90 days was 0.88and Poisson's ratio is about 0.25.
The using of hexagonal specimen to find the strength of concrete givemore factor of safety in structural design that because strength determined from hexagonal specimens will be slightly smallerwhen compared with results determined from cylindrical.
Main Subjects
Engineering & Technology Sciences (Multidisciplinary)
Topics
American Psychological Association (APA)
al-Saqi, Muhammad Mustafa Kamil. (2012). A proposed hexagonal control concrete specimen in lieu of other standard types. (Master's theses Theses and Dissertations Master). University of Technology, Iraq
https://search.emarefa.net/detail/BIM-419677
Modern Language Association (MLA)
al-Saqi, Muhammad Mustafa Kamil. A proposed hexagonal control concrete specimen in lieu of other standard types. (Master's theses Theses and Dissertations Master). University of Technology. (2012).
https://search.emarefa.net/detail/BIM-419677
American Medical Association (AMA)
al-Saqi, Muhammad Mustafa Kamil. (2012). A proposed hexagonal control concrete specimen in lieu of other standard types. (Master's theses Theses and Dissertations Master). University of Technology, Iraq
https://search.emarefa.net/detail/BIM-419677
Language
English
Data Type
Arab Theses
Record ID
BIM-419677
