Installed quickly with less labor, maintenance-free precast concrete box culvert bridges deliver a long service life. These eight box culvert designs demonstrate why precast is the best choice for a variety of site conditions.
By Gary K. Munkelt, P.E.
Maintenance and replacement of bridges over small streams are ongoing concerns for transportation agencies responsible for their upkeep. In recent years, however, infrastructure funding has not kept up with maintenance needs, and when bridge maintenance is not performed, the structures fall into disrepair.
A decision must be made as to when a bridge needs to be replaced. Should the bridge be replaced in kind, or are there better alternatives? The decision will be based on considerations such as cost, complexity of design, available materials and amount of time the highway is closed to traffic. Future maintenance should always be a part of the decision-making process. Read More »
A staff engineer reports on pre-assessment audits for the NPCA Plant Certification Program.
By Evan Gurley
Editor’s Note: In the first two parts of this four-part series, we addressed 10 of the most common problems encountered during a typical pre-assessment plant inspection relating to Chapters 1 through 5 in the NPCA Quality Control Manual for Precast and Prestressed Plants. In parts three and four of this series, we are focusing on product-specific deficiencies relating to Chapter 6, “Special Requirements,” of the NPCA QC Manual. The first three parts of this series were published in the January-February 2012, March-April 2012 and May-June 2012 issues of Precast Inc.
Side-stepping the requirement detailed in Chapter 6 of the QC Manual will land you a deficiency for products that are designed with steps cast into the product. Deficiencies are far too common with this requirement, as the specifics are often not fully grasped.
The NPCA QC Manual states:
“Step vertical and horizontal load testing must be performed according to the applicable sections(s) of ASTM C497 once per year, per step design used and whenever a new step supplier is used. The step testing must be performed in the precast plant in the product for its intended use. The testing must be performed or witnessed and results documented by a member of the precasters Quality Control Department. The loads achieved must meet the requirements of ASTM C478.”
This requirement is clearly laid out in the applicable sections in the NPCA QC Manual, but deficiencies in these sections are common. Read More »
This month we are pleased to feature Concrete Systems Inc. as part of our Meet a Precaster blog series. The following answers have been provided by Mike Worden, President of Concrete Systems Inc. and NPCA Board Member.
Don’t forget to check out all of our Meet a Precaster blog posts and if you’re an NPCA producer member and would like to be featured in a future Meet a Precaster post, please send an email to NPCA’s director of communication, Kirk Stelsel.
Q: Where are you located?
A: Hudson, N.H. and Londonberry, N.H.
Q: How long have you been a member of NPCA?
A: Since 1974.
Q: What are the best benefits of NPCA membership?
A: To establish and strengthen the relationships with our associate members who are so very important to our day-to-day operations and to to keep abreast of the latest developments, opportunities, and challenges within the precast concrete products industry. NPCA also allows us to have face-to-face exchanges with other precast producers regarding these issues, and sharing ideas is commonplace and beneficial to all of our efforts. It boils down to having a shared commitment to a common goal.
Q: What products do you produce?
A: Manholes and catch basins; Uwall, T-Wall, and L-wall retaining wall systems; box culverts; rigid frame bridge systems; CON/SPAN and BEBO bridge systems; box structures; commercial septic tanks; stormwater retention systems; median barrier; sound walls/noise barriers; bridge decks/slabs /abutments/wingwalls; headwalls; fire cisterns; grease traps; tunnels; electrical vaults; rail platforms/stations; custom structures.
Q: Have you been introduced to any new products lately?
A: Yes, we have introduced a new retaining wall system which we are quite excited about – “Uwall” – short for Universal Wall System. We feel it is a very uniquely engineered wall system which offers Read More »
This month we are pleased to feature Shea Concrete products as part of our Meet a Precaster blog series. The following answers have been provided by Greg Stratis, Manager and current NPCA Board Member.
Q: Where are you located?
A: We have three locations Amesbury, Wilmington and Rochester, Mass.
Q: How long have you been in business?
A: Shea has been in business since 1949. In September 1999 we purchased Read More »
This month we are pleased to feature Wieser Concrete Products as part of our Meet a Precaster blog series. The following answers have been provided by Andy Wieser, President and current NPCA Board member.
Q: How long have you been in business?
A: My father, Joe Wieser, started the business in 1965 with just Read More »
This year MBK Maschinenbau GmbH, based in Kisslegg, Germany, celebrates its 50th anniversary.
In 1961 Georg Pfender started a little machine shop in which, a few years later, he designed and built his first cage machine for a local concrete pipe producer. From there, MBK’s success story took off and the original design for straight cages was quickly updated to bell cages.
For the second generation, Albert Pfender, a mechanical engineer, succeeded his father in 1985 and invested his time and energy in consistent growth of the company. He continuously updated the machines to available technology and optimized the service quality. Meanwhile, more than 800 MBK cage machines had been installed worldwide, and an international service team with 15 technicians had been established. In Kisslegg, 80 employees and about 40 representative offices worldwide handle customer inquiries and interests.
In early 2009, MBK founded a daughter company in the United States, where three service technicians, a parts manager and an administrator handle the North American market. Networking and partnerships put MBK Sales & Service Inc. in a strong position to face the challenges of the reviving U.S. and Canadian markets. Read More »
Precast box culvert crossings become integrated in a renowned bicycle trail system in Illinois.
By Michael D. Cole
In terms of bicycle trails, the intricately planned system established by Madison County Transit (MCT), located in the southwestern region of Illinois, has emerged as a popular refuge coveted by nearby recreational enthusiasts, while also becoming a project envied by other municipalities.
Developed over the last decade, the rapidly expanding and near-complete bicycle trail system now spans more than 100 miles of which 75 are operated and maintained by Madison County Transit.
Construction of the trail system, located just east of the Mississippi River and only a short drive from St. Louis, has sped forward with a Lance Armstrong-like speed since MCT first developed the idea back in the early ’90s. Read More »