Recent content by Roadwork

If MERV 8 is minimum ASHRAE design standard (and is infact what we have in all our facilities), how would I determine what the maximum MERV would be for the system before modifications would be needed? Just asking based on ASHRAE's current recommendation (i.e. If you can't use MERV 13, use the...

Yes, the goal is to lower the risk of transmitting COVID in occupied spaces via HVAC systems. So, sounds like we would certainly need a designer.

MEs, Looking to find out what is involved in upgrading commercial HVAC systems to HEPA filters. Just trying to get a feel for the magnitude of this kind of effort, so I can come up with a ROM. Currently have a variety of systems: Trane, Carrier, CoolAir, and AAON, with filters in the MERV 8...

Ron - Where can I read more on the relationship between stability and moisture content?

To clarify, no explanations on the effect of excessive moisture in aggregate. That's not the question. Since the density-moisture curve for a given sample, is only based on a few data points, the majority of the curve is an extrapolation. Isn't it possible that even peak of the curve could be...

Several DOTs have the standard requirement, that aggregate base course be placed with a moisture content within 2% of optimum. Was discussing the reason for that requirement, with a co-worker recently. So, why is the standard set at 2%? Why not 1.5%, 2.5%, or 3%?

Thanks, and thanks for the link.

On a 130-180 gal wetwell for a sewage grinder pump, from what I have been able to gather (and this is not my field) it seems like Fiberglass Reinforced Polyester has been the material of choice. However, they also come in HDPE. What are their any benefits to choosing one material over the other?

Looking for some input on who puts on good continuing engineering/P.E. training seminars/courses in transporation or facility construction & design. My employer will pay for one course & travel per year. The course I wanted this year fell through, so now I am looking for a new one. Any...

...this is asphalt base (25 mm nominal)

Yes, several areas with raveling...and there is traffic on it. The large stone is segregated, and the course is a single 4" lift.

Anyone have experience (and success) with repair of segregation in a newly placed asphalt mat, other than to remove and replace?

Looking for comments/feedback on a contractor requested design change for the HMA base course on a 12,000 ADT roadway. They want to use a 3/4" mix, instead of the specified 1" mix for the base course.

Can anyone provide some insight on the pros/cons of one gate valve over another for water distribution systems? If I remember right, when I worked for a county water utility (along time ago), they almost exclusively specified double disk gate valves in new construction.

May want to look into fabric/poly interlayers. I was first introduced to it when I moved to Maryland three years ago, and although haven't used it myself yet, I've heard that it has produced very good results on airfields taxiways here. I have also seen it being used on County roads in Southern...