My favorite quote from WOC 2013, "Let pervious be pervious, and men be men. " Matt Offenberg Continue reading

Matt Offenberg Continue reading

Every year, pervious concrete gets bigger at World of Concrete, and I'm excited for what's in store for 2013! First, there will be educational sessions. Monday starts with an "Introduction to Pervious Concrete Pavement Construction" (MO48) where Dr. Brown and I will give an exciting overview of pervious concrete including construction, proportioning, testing, site design, and launching a contracting business in the pervious market. On Tuesday (TUPCW) the Tenessee Concrete Association will offer the pervious concrete contractor certification examination. Wednesday keeps the excitement rolling with Dr. Kevern's talk "10 Things Contractors Need to Know for Successful Pervious Concrete" (WE133). Along... Continue reading

I'm delighted to have company now that Bay Area Pervious Concrete has added a legitimate pervious concrete blog. Continue reading

Subcommittee C09.49 met yesterday at ASTM's winter meeting in Atlanta to continue development of testing standards for Pervious Concrete. Here are a few highlights. Continue reading

With the committee chair's trip canceled at the last minute, a surprise guest chaired the Fall 2012 ACI 522 meeting -- me! Here's what happened: 1) While a little behind schedule, the committee continues to make progress on the third version of ACI 522R. Based on where we stand, I'd guess the committee is still a year away from submitting to TAC. Norb Delatte reported his task group will submit a draft that includes structural design tables. 2) The standard details are coming closer to reality. The original intent behind this was to create a stand-alone document to post online... Continue reading

Live report from the ACI Social Media session happening now in Dominion South. #aciconvention for more. Continue reading

While it's the third year of the Bunyan Pervious Roast, it is my first year attending. Based on what I'd heard, I wasn't sure if it was more of a lecture series, day-long demonstrations, or an R&D event? One day in, it seems to be more of a group think-tank. Sure, it's a chance for those new to pervious to learn all about it. It's also an opportunity for contractors to try new tools and techniques. Most significantly, however, it's a place for the industry to come together, to discuss the future of pervious concrete, in all aspects: mixtures, construction... Continue reading

Late last year, the EPA issued Washington DC a new MS4 stormwater permit. Continue reading

The most common question I hear is, "What is a good result for C 1747?" Continue reading

It would be cool to say that the committee that oversees the NRMCA Pervious Concrete Contractor Certification is a super secretive society that flies in for monthly meetings, in their cloaked rocket planes, to meet in a remote, hidden underground fortress. But, in truth, it's a much more pedestrian group of designers, contractors, and concrete producers that have irregular conference calls to provide guidance to the NRMCA on changes in the market and technology that might impact how they run their certification program. In our committee meeting last month, we made some minor changes to the policies that govern the... Continue reading

It can't get much more fun than this! This has come up enough that we need to have a good, wonkish discussion of definitions for pervious concrete. With the publication of ASTM C 1747-11, ASTM now has an official definition for Raveling: raveling, n—the wearing away of a pavement surface due to dislodgement of aggregate particles. Also included in C 1747 is a definition for Design Density: design density, n—the mass of a unit volume of pervious concrete based on the theoretical mixture proportions and void content and where the unit volume includes the volume of the solids and the... Continue reading

Regular readers will remember that we are getting closer to having a new test standard for pervious concrete hardened density. While it is not yet published, ASTM has assigned a number to the new standard: C 1754 - 12. This test will be known as "Test Method for Hardened Density of Pervious Concrete". Looking at its applications in the next 3-5 years, it will probably be used mostly as a research tool. It will take a few years to build up a data set that will give the ACI 522 committee guidance on proper specification limits to incorporate into ACI... Continue reading

The flowers are blooming, the bees are buzzing, and the pervious people are meeting -- it's spring! If you weren't in Dallas, here's what you missed: 1) Standard Details -- The ballot to approve the new standard details for pervious concrete pavements failed miserably. All of the comments have been sent back to the task group to rework and ballot a new draft within 30 days. 2) 522.1 -- TAC has approved the committee's response to their comments. ACI will publish the draft in May for public comments. If the public comments go well, we could be published by the... Continue reading

It's official! The new ASTM test for determining the raveling potential of a pervious concrete mixure has been published as C 1747-11. You can download a copy here. If you're not familiar with the test, it has been discussed in previous blog posts here and here, and this article here. Continue reading

What is this ... action to find ME not persuasive!?! Continue reading

If you missed my video blog entry on CC's site, you can watch it here. Continue reading

In the NRMCA training for both stormwater designers and contractors, we teach the use of header curbs between the pervious concrete and adjacent asphalt to prevent water from migrating from under the pervious concrete to under the conventional pavement. Such flows often cause subgrade failure under the plain pavement due to differential subgrade support as the area near the pervious concrete tends to be saturated while the soils farther away tend to be drier. Here are the slides from the contractor training class: Continue reading

ACI has released the first compilation of peer-reviewed technical papers specifically focused on pervious concrete, "ACI SP-282 The Leading Edge of Pervious Concrete". This compilation includes papers presented at the full-day technical session held in New Orleans. Edited by Charles Weiss, tHe authors include some of the big names in the world of pervious concrete: Norb Delatte, Heather Brown, Narayanan Neithalath, John Kevern, Liv Haselbach, Zhifu Yang, and Matt Offenberg. A full listing of papers can be found here. Continue reading

It's always fun and exciting to see new technology for pervious concrete. This year at World of Concrete, I experienced a few exciting "firsts" -- here are my top three: 1) First time vacuuming pervious concrete with Ditch Witch's attachment for pervious concrete: Ditch Witch developed a head specifically for cleaning pervious concrete. By combining pressurized water with a strong vaccum they created a tool that was able to remove sand from the surface of five day-old pervious concrete without causing raveling. I don't have the technical specifics, but I can safely say this vacuum really sucks! 2) First time... Continue reading

If you're looking to learn more about pervious concrete, there is no better opportunity that this year's WOC! Continue reading

Saw in an email that the new Standard Test Method for Determining Potential Resistance to Degradation of Pervious Concrete by Impact and Abrasion will be numbered C 1747-11. Continue reading

If you ever find yourself in south Georgia, at the crossroads of cotton and peanut country, near the home of the "Wild Chicken Festival" you'll be in Fitzgerald. Recently, I had a chance to visit the Wal-Mart there. Continue reading

To say the body of knowledge in pervious concrete is growing is an understatement -- it is exploding! This week the ASTM meeting added to that explosion with the first ASTM Symposium on Pervious Concrete. The symposium featured eight speakers covering some of the latest research and updates on test methods for pervious concrete. Some of the more interesting presentations included: "Validation of the Performance of Pervious Concrete in a Field Application with Finite Element Analysis (FEA)" Md. Ashraful Alam, Liv Haselbach, William F. Cofer, Washington State University, Pullman, WA USA "Pervious Concretes Pore Structure Characterisation by 3D image analysis... Continue reading

BREAKING NEWS: The United States Federal Government's new pervious concrete specification has finally been published! The new section, numbered 32 13 43, replaces the old section 32 13 13.06 which was the plain concrete pavement spec that had pervious language scattered throughout. Likewise, an updated 32 13 13.06 has also been published to remove the old pervious concrete references. A copy of the new pervious concrete specification can be downloaded for free from the National Institute of Building Sciences. Many thanks to the project team that made this happen. Specifically, Chuck Weiss from the Army Corps of Engineers, Toy Poole,... Continue reading