Evaluation of Pre-Strain of Reinforcing Bars on Flexural Crack Widths of Rectangular Cross Section Reinforced Concrete Beams
By K. Suhara, Y. Tsujll, R. Yoshino and Y. Okamura
Concrete Journal, Vol.53, No.2, Feb. 2015
- Synopsis
- This paper reports the influence of pre-strain on the flexural crack width of rectangular cross section RC beams, from the viewpoint of pre-strain occurring in tension steel, based on the results of flexural loading tests carried out on 1) beams mechanically pre-tensioned by pre-tensioning the tension reinforcements (PPC beams) , 2) beams chemically pre-tensioned by using expansive concrete with an expansive admixture (CPC beams), and 3) non-pretensioned beams (RC beams). This paper further reports that the flexural crack width for the same external moment on the PPC and CPC beams was smaller than for the RC beams, and that while the difference amount is generally equivalent to the mechanical pre-tension or chemical pre-tension introduced into the tension steel, in the case of the PPC beams or the CPC beams, a flexural crack width reduction amount exceeding that pre-strain was observed in some CPC beams.
- Keywords:
- RC beam, flexural crack width, rectangular cross section, pre-strain, pre-tension, chemical pre-strain, expansive concrete
