Experimental and analytical study of SIMCON tension members

• Published in: Mechanics of materials Vol. 28; no. 1; pp. 181 - 195
• Main Authors: Murakami, Hidenori, Zeng, Jack Y.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Lausanne Elsevier Ltd 1998; Amsterdam Elsevier Science; New York, NY
• Subjects: Applied sciences; Buildings. Public works; Concretes. Mortars. Grouts; Exact sciences and technology; Fiber bridging force; Materials; Properties and performance tests of mortar and hardened concrete; SIMCON; Steel fiber reinforced concrete; SIMCON; Steel fiber reinforced concrete; Fiber bridging force; Crack bridging; Uniaxial tension stress; Fiber reinforced concrete; Rupture; Testing equipment; Steel fiber; Experimental study; Random medium; Modeling; Tension test; Crack propagation
• ISSN: 0167-6636; 1872-7743
• DOI: 10.1016/S0167-6636(97)00060-4

The strength and ductility of slurry infiltrated mat concrete (SIMCON) tension members were investigated both experimentally and analytically to construct a mechanical model for simulating tensile force–displacement relationships. In addition to standard strength testing, special tests were conducted on tension specimens with preset cracks to determine the interaction between steel fibers and the cement matrix near an opening crack. These tests were conducted on two sets of preset-crack specimens: (i) with symmetrically inclined fibers and (ii) with aligned fibers having variable debonded lengths on each side of the crack. Using measured bridging forces of inclined fibers, an efficiency factor of plane random fibers, compared to aligned fibers, was determined to be approximately 0.58. It was found that the ductility of SIMCON mainly stems from plastic deformation of steel fibers rather than fiber pull-out. SIMCON tensile response was characterized by elastic, nonlinear hardening and softening regimes. The hardening response was notch insensitive without multiple crack formation. In the elastic regime, only minute stiffness reduction was observed. The nonlinear hardening regime was characterized by internal damage growth without visible crack formation and ended with the appearance of a co-linear set of partial cracks. The softening regime was described by a localized failure of fibers with variable failure strains at the co-linear cracks. Based upon the experimental observation that a co-linear set of partial cracks form at the ultimate composite stress, upper and lower bounds of the SIMCON stress–strain relation in the hardening regimes were obtained.