Life365 with concrete cover greater than 75 mm
Life365 with concrete cover greater than 75 mm
(OP)
The current version of Life 365 does not allow running with cover > 75 mm. I want to run with larger cover to get 75 year design life to first repair, for raft foundation slab with granular plus paving and parking above it. Since the cracks are not visible, they should not be an issue. The surface crack width (as opposed to crack width at the bar level) is not a significant factor in the rebar corrosion. Earlier versions allowed running >75 mm cover. Any idea how to get around this?






RE: Life365 with concrete cover greater than 75 mm
BA
RE: Life365 with concrete cover greater than 75 mm
RE: Life365 with concrete cover greater than 75 mm
BA
RE: Life365 with concrete cover greater than 75 mm
RE: Life365 with concrete cover greater than 75 mm
RE: Life365 with concrete cover greater than 75 mm
My suggestion was not to alter the actual dimensions of the concrete slab but to alter the dimension input into your program such that a cover of 75mm could be used instead of the actual cover. Let's say the depth of the concrete slab is 600mm and a cover of 150mm is required; I was suggesting you input a slab depth of 525mm with a cover of 75mm which should result in the same structural performance. The slab shown on your drawings would be 600mm with 150mm cover; in that way, you have tricked the program into thinking the slab was thinner than it was.
BA
RE: Life365 with concrete cover greater than 75 mm
To Hokie66 - Life 365 models the time to rebar corrosion in chloride environments, using Ficks law of diffusion and based on user defined Canadian Standards Association (CSA) concrete classifications, concrete cover, protection system, and other input parameters. You can download Life 365 from the internet, free of charge. It is almost essential software for the engineer where greater than the standard 40 year service life (CSA S413 Parking Structures) is desired. However, as you live in Australia, where I would guess they have no need for road deicing chemicals (generally corrosive chlorides) you may have no need for it.
RE: Life365 with concrete cover greater than 75 mm
RE: Life365 with concrete cover greater than 75 mm
Note that CSA S413 "Parking Structures") does not have provisions about crack width. Its provisions are mainly directed at preventing ingress of the chlorides into the uncracked concrete.
In any event, the bars could likely be chosen to control the crack width, so that would not seem to be a compelling reason to have limited the input cover for Life365 to 75 mm in Life 365.