Purpose –
Reinforced concrete (R.C.) beams are part of the structure so their design
depends on the structural code and its requirements. In this paper, two
simply supported R.C. beams were designed in terms of flexural and shear strength
design requirements and investigated in terms of deflections
and crack widths, when subjected to two asymmetric
concentrated loadings, where one load is double the other one. Both beams had
dimensions of 3,500mm length, 200mm width, and 300mm height. The first beam
(beam B1) was designed according to the combination of the structural
requirements of American and Saudi building codes (ACI318-and-SBC304), while
the second beam (beam B2) was designed according to the structural
requirements of Eurocode (EC2). The paper aims to discuss these
issues
Design/methodology/approach – The
design of ultimate capacity (section capacity) to design both flexure and
shear capacity according to the design provisions in EC2 code deals with the
Ultimate Limit State Design Approach, while it deals with the Ultimate
Strength Design Approach according to the design provisions in both ACI318
and SBC304 codes. In the serviceability (mid-span deflection and flexural
crack width) check, the three codes deal with the Serviceability Limit State
Design
Approach
Findings
– The laboratory behaviour of both test beams was as expected in flexure and
failed in shear, but there was more shear cracks in the left shear span for
both beams. This refers to the left applied loading and the spacing of shear
links, where the failure occurred at the higher loading points. Perhaps, if
the number of links was increased in the left side of the beam during the
manufacture and reinforcing of the beam, the failure loading will be delayed
and the diagonal cracks will be decreased
Originality/value – From this
study, it was concluded that: the ACI318 and SBC304 design approaches are
safer than the EC2 design approach. The EC2 design approach is more economic
than the ACI318 and SBC304 design approaches. The structural behaviour of
both test beams was as expected in flexure but both beams failed in shear.
The shear failure was in the left side of both test beams which was referred
to a high loading point. Diagonal cracks followed the applied loading until both
beams reached to the failure
Keywords
Experimental investigation, R.C. beams, Deflection and cracks, Flexure and
shear
Theoretical
design, EC2, ACI318-and-SBC304
|