288 The parameters from Table to be applied are dependent primarily on the failure mode, pull-out or splitting. Further distinctions are made to account for differences in bond conditions within each failure mode. The rationale underpinning the following rules is given in fib bulletin Bond and anchorage of reinforcement Background to proposed revisions in the fib Model Code Table 6.1-1: Parameters defining the mean bond stress-slip relationship of ribbed bars (acc. to Eqs. (6.1-1) to (6.1-4)) b Pull-Out (PO) Splitting (SP) bmax bu,split,2 Pull-Out Splitting Good bond cond. s
Fib Bulletin 65.pdf
310 6.1.5 Special circumstances Slipform construction The value of coefficient η 2, Eq. (6.1-20), should be taken as 0.7 for bars in structural parts built using slipform construction Bentonite walling The value of coefficient η 2, Eq. (6.1-20), should be taken as 0.7 for bars in concrete cast under bentonite or polymer drilling fluids. The suitability of the systems has to be proven by an independent approval process. For more details reference is made to fib Design Guide Design of anchorages in concretes (fib bulletin 58) Post-installed reinforcement Rebar connections using post-installed rebars are permissible for all applications where straight cast-in-place rebars are allowed. The design can be performed in a simplified way using the provisions for cast-in-place rebars in this code. However, the following restrictions must be considered: the system for inspecting the hole must be suitable for the application in question; larger minimum concrete cover; larger minimum clear bar spacing; limited design compression strength; special requirements for fire safety ECE (electrochemical extraction of chlorides) The correct application of electrochemical techniques for chloride extraction from or re-alkalisation of concrete does not cause any significant long-term reduction in bond strength, except where: AAR is induced in concrete containing susceptible aggregates by the electrochemical process; an appreciable amount of corrosion has occurred prior to treatment. Plain (unribbed) round bars are likely to be particularly susceptible to loss of bond in these circumstances, see subclause fib Bulletin 65: Model Code 2010, Final draft Volume 1 271
The American College of Obstetricians and Gynecologists' practice bulletin on bariatric surgery and pregnancy (ACOG, 2009) stated that bariatric surgery should not be considered a treatment for infertility.
Een deel van de fib-bulletins dat sinds 1999 is uitgebracht, is via deze pagina exclusief voor leden van Stufib te downloaden. Dit betreft de bulletins tot en met nummer 68. Overige geïnteresseerden kunnen fib-bulletins via de site van fib bestellen.
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