CIVE 2700 Lecture Notes - Lecture 2: Work Hardening, Ultimate Tensile Strength, Rebar

• School: Carleton University
• Department: Civil Engineering
• Course: CIVE 2700
• Professor: John Gales

Document Summary

Important to design product to resist deformation, but if it deforms due to loading: Do(cid:374)"t e(cid:454)(cid:272)eed (cid:455)ield stre(cid:374)gth & a(cid:448)oid (cid:272)atastrophi(cid:272) failure: yield strength is normally used in canada for design purposes instead of tensile strength b/c a material will undergo undesirable plastic deformation at stresses above the yield stress. Yield strength: so(cid:373)e steels do(cid:374)"t e(cid:454)hi(cid:271)it a well-defined yield point. (gradual transition from elastic to plastic, rule of thumb to define yield stress (yield strength) of materials: 0. 2% offset method (typically for aluminum). 0. 5% extension method (for reinforcing bar of steel grade 40, When a metal plastically deforms, it strain (work) hardens becoming stronger and harder. Typically applied in direction of loading but can be transversely applied to measure. Have a maze-like wiring pattern on the foil backing. Under stress & strain, these change shape, causing the wires to change resistance. Measuring load load cell (application of many strain gauges)