The Wisconsin Concrete Pipe Association was established on October 23, 1933 and has been working with design engineers for over 75 years.
The Executive Director, Paul Lohmiller M.S., P.E., is a 1974 Graduate from Valparaiso University and has a Masters Degree from Marquette University in Public Works Admin. Paul has worked for several consulting firms, and a City Public Works Director, all in Wisconsin. Lohmiller was a Resident Engineer for Milwaukee Deep Tunnel Sewer project, and is also a guest lecturer for Gateway Technical Institute for Civil Engineering Technician
The Wisconsin Concrete Pipe Association is a technical and educational trade association representing the concrete pipe manufacturers of Wisconsin. The members manufacture reinforced concrete storm sewer pipe, reinforced concrete sanitary sewer pipe, non-reinforced concrete sanitary sewer pipe, non-reinforced concrete culvert pipe, manholes, reinforced concrete boxes, reinforced concrete elliptical pipe, reinforced concrete arch pipe and a variety of precast concrete connectors.
Concrete pipe has long been recognized by specifiers as the most dependable, durable and strongest product available for culverts, storm sewer and sanitary sewer pipe.
The capacity of reinforced concrete pipe has been shown by numerous studies to be as good as any other smooth wall material available. Some studies have shown that the lab numbers for concrete pipe for Mannings "n" to be .009 to .010. Many engineers use a .012 to .013 Mannings "n" to account for field conditions, when doing capacity studies. Non-engineers promoting new products do not understand these fundamental engineering factors of safety and promote their product based on lab values. Concrete pipe manufacturers have always understood the safety and dependability of reinforced concrete pipe and support the design engineers when recommending safety factors.
Design software is available for reinforced concrete pipe (SIDD) for pre-cast concrete boxes (Boxcar) and for cost analysis of pipe installations (Life Cost). Recent studies have shown that the concrete pipe software (SIDD) is very dependable and accurate when analyzing soil properties, but that software for flexible pipe does not give accurate readings.
The joints in reinforced concrete pipe are dependable and of a very high strength compared to other products. Differential deflection experienced by polyvinyl chloride pipe (PVC), high density polyethylene pipe (HDPE), and metal pipe is not found in rigid concrete pipe joints and with the use of proper gasketing material can insure a dependable system without fear of infiltration or exfiltration from the sewer system.