CSA N291-2019 pdf free download

CSA N291-2019 pdf free download.Requirements for nuclear safety-related structures.
7.22.2
A temperature difference between the middle and the surface of the structure shall not exceed 20 C
7.2.2.3
The temperature limits in Clauses 7.2.21 and 7.2,21 may be exceeded only at the discretion of an engineer if it is proven that the tensile stresses arising from the temperature differences are always less than the current tensile strength of the concrete.
7.2.2.4
The temperature of the concrete shah be monitored during concrete hydration to enwre that at no time are the temperature limits specified in CSA A23.1 and Clause 7.2.2.2 of this Standard exceeded
An engineer shall approve the type, amount, and location of instrumentation for temperature measurements and the data collection schedule.
Note: Mon itoiwsg instrumentation imgfir not be necessary when repairs. portlai repfocenients. 0, smofl placements of concrete ore peifonned and an engineer is wfr4led that the heat of %‘drorio,, Is not of concern.
7.2.3 Waiting periods
Fresh concrete in walls and wspended slabs that are restrained by continuous reinforcement shall not be placed against existing concrete untl the temperature differential is no greater than 8 c between the following:
a) average ambient temperature dunng the 48 Ii penod prior to placing the fresh concrete; and b) the temperature of the closure pour measured at the centre of the pour,
The temperature drfferrntiol may be increased at The discretion of the designer when post tensioning is used. Annrx b provides rrconinwnded waiting period; for the placing of frv,h concrete odacrnt to hardened concrete to satisfy the Frquwemersts of tilts Ctauscfrw various combinations Cf temperature. tpprs of cements, and placrmen r thicknesses,
3) The temperature diffcrtntral may be hilscr than S t, provided that tests are per7’orlnrd to determine any drleterlous effects due To possibfe cracking Cf concrete for green geometries These effects ore To be applied to the design requirements given In this Standard.
7.2.4 Grout temperature
Cement grout shall be placed in accordance with CSA A23.I. In cold weather, the temperature of grout during mixing, pumping, and curing shall be maintained In accordance with Clauses 6.8.7.2 and 6.8.7.3 of CSA A23.1.
7.3 High-density concrete placenwnl
High-dens4ty conciete shall be consobdated by controlled vibration that prevents segregation and
settlement of the aggregates.
Not.: The method of consoildation of high ‘density concrete speqf led in ACI 309A should be used
7.4 Stainless steel
Welding procedures shall be qualified in accordance with CSA W47.1, with suitable allowance for welding stainless steel base material and filler material.CSA N291-2019 pdf free download.