Hi, could any one of you proffesional grader men out there be willing to tell me exactly what final trim is,(in reference to reconstructing a road ready to be sealed), and give a brief description on how its done. I'm not sure if the technique I've been shown is right or not.
Basically when we put in top course gravel we slightly over fill to allow for compaction and settling thru rolling and traffic running it, usually leave it a number of days to bake out and go hard then depending on when it is to be have the A/C laid we put new cutting edges on the grader and trim it to the correct depth and shape depending on the depth of the A/C. Usually check with string line/tape measure to get the crown height right then a block of wood or something that is the right thicknes placed on the crown and pull the string back to the lip of the kerb to make sure its a straight grade from the crown to the kerb lip or what ever the A/C has to tie into. We usually use a loader or backhoe to pick the trimmings or a small elevating scraper if one is on site, once its on grade it gets a slurry up and left to bake out till inspection day when the Council/Engineers will go thru and check the shape with string line tape etc, they allso do a wheel test to check for pavement deflection before giving the OK to A/C. The main thing is to not cut to much off in the final trimmig process as you cant stick it back on without it laminating and if you are to deep it is expensive to fill it up with A/C. Its a thing you get better at the more you do it. Just spent last week trimming out a road ready for a preseal inspection yesterday but here in sunny QLD weve just had 200mm or more rain and it shows no signs off stopping for the next couple of days at least so there wont be any A/C going on this week. Cheers RDG
Hi there RDG, Thankyou very much for that explanation. What was explained to me was not far off the mark to what you just described, so all is good. Wish we could get some of that rain down our way in NE VIC, none of our seasonal creeks have had water in them for about four years. much appreciated, mick.