| Author | Estanero, Romeo A. |
| Call Number | AIT Thesis no. 186 |
| Subject(s) | Reinforced concrete
Concrete beams--Testing
|
| Note | A thesis submitted in partial fulfillment of the
requirements for the degree of Master of Engineering in the SEATO Graduate School of Engineering, Bangkok,
Thailand. |
| Publisher | Asian Institute of Technology |
| Abstract | This paper sets out details of the tests conducted on forty-one reinforced concrete square and rectangular beams tested under various combinations of twisting to bending moment. The size of transverse and longitudinal reinforcing were varied for a constant spacing of the transverse reinforcements for all
beams. All beams had equal top and bottom longitudinal steel.
The beams were loaded simultaneously\' with bending and twisting moments, the ratio of twisting to bending moment being held constant throughout the test. A constant bending moment was maintained within the middle third and the bending and twisting rotations within this region were measured throughout the test in order to determine the effective axis of rotation mat the plastic hinge. It is shown that for any given section the angle which the rotation axis makes with the transverse cross section is almost directly proportional to the ratio of twisting to bending moment. For a single value of torsion to bending moment, it is shown that this angle depends on the ratio of the transverse to longitudinal reinforcements, and on the shape of the section.
The theory proposed by COLLINS, et al (1966) enables
the failure torque to be estimated quite closely for the
square sections but is less satisfactory for the rectangular
sections. There is less agreement between the predicted and
experimental directions of the axes of rotation especially
for high values of torsion to bending moment ratio. Except for beams failing in the shear span, all beams tested under the ratio of twisting to bending moment of 0.4, 0.6, 0.8 and 1.0 failed by yielding of the bottom steel and the development of large tensile cracks on the sides, the inclination of these cracks with the vertical, depending on
the ratio of twisting to bending moment. The appearance of
tensile cracks as well as crushing on the top surface of the beams in the region of constant moment characterized the failure mode of the beams in this investigation. |
| Year | 1967 |
| Type | Thesis |
| School | Student Research Before 1980 |
| Department | Other Field of Studies (No Department) |
| Academic Program/FoS | Thesis (Year <=1979) |
| Chairperson(s) | Jackson, N. |
| Examination Committee(s) | Chiu, Arthur N.L. ;Lorell, William.W. |
| Degree | Thesis (M. Eng.) - SEATO Graduate School of Engineering, 1967 |
