An issue has come up a few times now which has really bugged me. Whenever a road has on-street parking, it appears that cars parked on the street are within the departure sight distance triangles (per AASHTO). For example, on a project that I'm working on with a 40 mph design speed, if you plot...
We proposed this on one of my plans and the City I'm working for is concerned that the slurry seal won't bond to the ARHM like it would on a typical ACP. I've never heard of this concern and was wondering if anyone on this forum has any opinion on this.
Thanks!
I'm a PE in CA who has designed 100s of ADA ramps (mostly road curb ramps, but some site ramps too). Typically, we show a precise graded detail on the plans (actual elevations, grades, horizontal control) so I'm confident the contractor can construct it to be ADA compliant in the field. However...
Thanks for the response Ron. As a follow up question I now thinking that I should revise the Greenbook to say something like the w/c ratio needs to be less than 0.50 for PCC pavement, driveways, sidewalks, curbs, etc. My only concern is that this will increase the cost of those items. Do you...
I am a roadway designer and typically write specifications using the Greenbook. I recently had a construction manager reject a concrete pavement submittal because he thought the w/c of 0.57 was too high (even though the concrete compressive strength and slump was met) and recommended that it be...
I typically estimate asphalt concrete pavement in tons by using the formula [Tons = Cubic Feet of material x Density of ACP (148 lbs/cf) / 2000]. I need to estimate asphalt rubber hot mix in tons and am trying to find out if it's density is still around 148 lbs / cf. Anyone know?
I have been the roadway designer on multiple roadway widening project for various cities. I have had a few cities request that we provide a 2 foot wide and 2" thick cold mill and overlay adjacent to the saw cut line which is typically 1' from the edge of gutter. I have also seen this on utility...
AutoTurn is great to design driveways because you have backup in case anyone questions you. Just make sure to clarify with you Client what truck turning template you are using so everyone is on the same page.
I am writing the Special Provisions (to modify the Greenbook 2009) for a road widening project in using the format where you reference the specific section and indicate how to modify it like [replace the first paragraph with the following] or [Add the following] like the example below.
SECTION...
I have prepared plans for a street rehab of an existing street where the existing street grades are over 5% in some areas. This project includes sidewalk replacement and the contractor is saying that he can't build a sidewalk with a slope greater than 5% because it is against the ADA (CBC in...
I work on a lot of roadway widening / rehabilition projects for various cities. I alway have a difficult time estimating how long the construction schedule should take. Mostly I estimate it by using previous projects but I don't have any back up to support my duration. Does anyone know of a book...
How can the controller of an existing 8-phase operating intersection be modified to accommodate an exclusive “scramble” phase? Since all eight phases are currently being used, would the scramble phase require an additional (9th) phase or can this be accommodated with the existing Type 170...
I have a situation where I need to design a curb ramp and if I used a 8.3% maximum grade, the curb ramp would never daylight because the adjacent road is at 10%. In situations like this, what is maximum length I should make the ramp? I thought I saw an ADA guideline once which stated to use 10'...
I think I confused you guys a little. The picture is not my project. It is a retrofitted ramp that I saw it near my house similar to what I need to do on my project. The ramp in the picture was added to put in a driveway, but the traffic signal was protected in place except for the base which...
Thanks Drumchaser. You're right in that a single adjustment would be adequate for AC pavement section reconstruction because cars wouldn't be allowed to drive on the surface until complete (unlike mill and overlay which the car can drive after milled).
I am working on road rehab project where several ramps need to be replaced to conform to ADA standards. There are a few ramps where existing traffic signals would be within the side slope portion of the new ramp. I have seen traffic signal bases modified with ramps before.
(see attached picture...
Thanks for the reply Drumchaser. Regarding your last sentence. I've seen contractors protect in place large electrical vaults and telephone vaults by adding tapered AC pavement. Do they typically do this with SD and SS manholes or water valves?
Also, on full blown AC pavement section...
Typically on all grind and overlay projects (where the existing and proposed finished surface is at the same elevations), I have always specified for all manholes and valves to be adjusted to grade without giving it a second thought. This is usually at the direction of the City I am working for...
I have slurry seal (type II) as a bid item for one of my roadway projects and need to know how to convert my SF quanity to ELT (extra large ton) because that's how the agency wants it. Does anyone know how to do this?
Thanks,
Raydefan
