Anyone have any insight or experience with vacuum testing for sanitary sewer mains, and/or any relevant testing specifications from a pipe manufacturer or water/sewer district? Quick background:
It’s standard practice for many local water/sewer districts to perform vacuum testing on sanitary...
We are in the process of selling our house and the inspector brought up concerns with our septic system. Turns out there's about 8"-12" of standing water in the leech field inspection port. The tank is 3-chambers, 1,500 gallons with a siphon in the last chamber. It appears that the siphon is...
We are designing a large truck delivery parking lot re-paving project and are adding a 12' wide concrete pan to replace a small portion of the existing asphalt. The geotech pavement resurfacing options are: (1) 11" of asphalt on 12" stabilized subgrade or (2) an 11" concrete section with 12"...
I am overseeing an asphalt overlay project, where some of the existing asphalt surface has started to show signs of stripping and aggregate loss, along with some damage from snowplowing operations, leaving some fairly large voids on the surface. The contractor has proposed to use a 12' screed...
I'm doing a preliminary alternatives analysis for replacement of a 38' span steel-beam bridge, and one of the alternatives I'm exploring is replacing with used rail cars. It seems to be somewhat common and appears to offer some significant cost savings.
I'm a civil engineer (not a structural)...
We recently re-designed a two-lane rural/suburban road with a widened asphalt shoulder, intended to allow safer pedestrian access in the road corridor. Stripped drive lane widths are 11' with a 7'-8' paved shoulder on one-side for pedestrians/bicycles. This was previously a 28' wide asphalt...
Trying to work with the DOT on an access permit application. Client wants to install a right-in/right-out access but DOT is balking because they say it gets ignored by motorists.
Besides the obvious options like signage and a concrete island 'pork chop' at the entrance, has anyone else figured...
Designing the repair for a corroded invert in a 15' (fifteen foot) steel plate culvert. I have a few examples from DOT for concrete invert repairs and they seem fairly straight-forward.
I'm trying to figure out if the design thickness of concrete is based on the size of the pipe, size of...
I've tried to search the forum but supisingly haven't found a lot of discussion regarding culvert rehab, at least not the with people's experience of product issues after construction has been completed.
The agency I do engineerng work for is considering slip lining numerous CMPs that are under...
I observed a site yesterday where observable ground movement has started to cause displacement and overturning in deck post footings and adjacent retaining walls. This building complex was built almost 30 years ago, and this recent movement has only occurred in the last two-three weeks. It...
I'm trying to find a reference to determine the maximum allowable incremental change in speed limits between signs.
As an example, you are driving in town on a rural highway and the current posted speed limit is 30 MPH. When you drive out of town the speed limit on the highway goes up to 60...
Here's the situation: 6-unit condominium complex with sump pumps in the crawl space of each unit. Sump pumps all pump to one 1-1/2" discharge pipe (flowing south to north). This existing discharge pipe is about 180' long and installed with a negative (uphill) grade. The sump pumps at the...
*Not sure if this belongs in the geotechnical forum, but I'll start here.*
I'm working on a proposed sanitary sewer design for new 15"-18" gravity-fed main, three total miles.
I just received a phone call from the geotechnical engineer and about 1000'-1500' of the proposed main crosses through...
I'm working on a design to install a foundation drain around an existing building. The site is flat and footers are 4' deep, so I have no place to discharge by gravity - it will have to feed back to a sump pump in the crawl space and I have some questions.
Is it important to have a separate...
I designed a 4" PVC SDR 35 sanitary sewer service line in very cold country. Standard cover here is 7' over sanitary sewer lines, but based on recent potholing it was discovered that we will have anywhere from 3'-5' of cover. Under these circumstances I would have liked to spec a pre-fabbed...
What is a typical design storm event for design of erosion control, specifically for turf-reinforcement blanket in a roadside ditch? Obviously the conservative design would include a design to accommodate a 100-year storm event, but this seems like overkill to me. The municipality I'm dealing...
I have a road project that is designed in an old creek bed, with large partially exposed rock (18" to 8' in diameter). Based on the geotechnical report, some of this rock is fractured and is "rippable" by a large excavator, other rock is expected to have to be blasted. Since the majority of...
I'm looking for a real basic construction cost number for bridge deck (in Square Feet) and for bridge abutments (in square-face foot). It would be helpful if these included a range. I can get my hands on costs for rebar, concrete, etc. but was hoping to get an overall number (unit cost)...
Preliminary drainage design for storm drainage (in a parking lot) behind retaining wall (approx. 8'-12' in height) includes curb and gutter with a storm inlet and a 12" RCP outlet culvert that discharges on the downhill side of the wall. Existing slope downhill of wall is approx. 2:1 and in...
