As I left off in the Introduction to this blog series:
To get the best concrete mix design and proportions, you need to….
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Concrete Mix Design: Art and Science – Introduction
We are rapidly approaching the 100th anniversary of the 1918 publication of Lewis Institute Bulletin No. 1, which contains Duff Abrams’ theory about the water/cement ratio. You would think that in 100 years the concrete industry would have performed enough research that the concrete mix design process would be standard. After all, there are only so many ways you can combine rock, sand, cement and water. The trouble is, there are so many ways you can combine rock, sand, cement and water – basically an infinite number. Not only are we unable to determine the best way to blend these 4 materials, but we are also unable to quantify some materials’ characteristics, such as particle shape and texture, as well as unable to characterize concrete performance, such as workability and segregation potential. For these reasons, and many others, concrete mix design is almost as much art as it is science. Continue reading
NRMCA 2013 Concrete Sustainability Conference in review
Two weeks ago I was just south of beautiful San Francisco to attend the NRMCA’s Concrete Sustainability Conference (along with the Research, Engineering and Standards Committee meeting). In the past, it seemed that most of the presentations at the CSC revolved around people saying, “My concrete has more fly ash (or slag, or magic pixie dust) than yours.” This year was different! While the materials people still led the way with “better concrete through modern chemistry”, there were other voices added to the choir. Continue reading
“Long Live The King!” Handling Priority Customer$
The number one cause of poor customer service are your priority customers. Priority customers can call at the last minute and demand service for which this industry is all too willing to comply. This of course means that the needed trucks are “stolen” from other customers causing them poor service. This is the prime cause of the origination of the old Ready Mixed Concrete saw “We never hurt the same customer twice in a row”. This is, of course, not a service statement but a reaction to providing poor service. Why provide poor service even once? Continue reading
That’s Not My Job!
Have you ever heard someone say, “That’s not my job.”? In today’s world, where so many options and opportunities assail us every day, the natural reaction is to try and focus on just a few things and specialize. This happens in our everyday, personal lives as well as our work life. From the homemaker, who knows how to cook 10 or 15 basic meals and cooks them over and over, to the computer programmer, who has programmed in 1 or 2 languages for 20 years and is now surprised to be out of a job, specialization has become the mantra of the past few generations.
This applies to the concrete industry as well. Vibrator operators don’t understand formwork and resteel fabricators don’t understand testing. This doesn’t just apply to the trades. Engineers don’t know the difficulties of delivering fresh concrete, and Architects don’t realize that a perfectly smooth concrete wall 40 feet high and 120 feet long is impossible to achieve. Let’s face it – except for a few limited conditions, the days of the Master Builder are over. I challenge you to find a single person with is a Master Electrician, Master Plumber, can (legally) install his own HVAC and finish concrete properly. This paragon of construction doesn’t exist! But that doesn’t mean that a builder can’t understand the basics of electrical work, plumbing, HVAC and concrete. We all need to step away from the attitude of “It’s not my job” and learn more about how our work affects the people around us. This is especially true of the concrete industry. Continue reading
Performance Concrete – The Next Steps
In my blog entry, “Let the bakers bake!” – http://www.commandalkonconnect.com/2012/10/08/let-the-bakers-bake/ back in October of last year, I posted a call to arms for new emphasis on converting to performance concrete specifications. Shortly after that I realized that even concrete producers did not have a consensus opinion on what constituted performance concrete and how willing they were to pursue it. In addition, I have posted several blog entries about the use of “f’c” for specifying strength, “Missed it by that much – Concrete Tests and f’c” – http://www.commandalkonconnect.com/2012/09/26/missed-it-by-that-much-concrete-tests-and-fc/ , and – “Superman, MacGuyver and Concrete!” – http://www.commandalkonconnect.com/2012/11/05/superman-macguyver-and-concrete/, and how in reality we don’t really practice what we preach. ACI 318 isn’t really being followed properly, which may explain some of their desire to totally revamp the document.
Now that I have the results of my latest survey on “U.S. Concrete Producers’ Attitudes toward Performance Concrete”, I think I have a better idea of what I want to do to encourage the use of Performance Specifications. Below is a summary of some of the results of the survey, plus my roadmap of what I think ought to be done to encourage Performance Specs. Continue reading
Concrete Blogging – The Year in Review (and other inspirations from Janus)
It is hard for me to believe, but this blog entry marks the end of one year of blogging for me. Even though I was reticent to start blogging at first, the favorable responses I have received from around the world have made it well worthwhile. Comments from friends, colleagues, people I know of from their writings, complete strangers and even the “cute young thing” who was about my daughter’s age have made me truly grateful to be in this industry. At the same time, I don’t think that I am in danger of winning the Pulitzer Prize for “Most Widely Read Blogger”. Let’s just say that I write for a very narrow niche market, but I think that I am read by a good number of people in that niche.
I’d like to thank Ron, Shawn and Michael at Command Alkon for “prodding” me to write this blog. I would also like to thank the people who have commented on my articles, both on the blog site and also in private communications off the site. It is nice to get occasional confirmation that someone out there really is reading my articles.
For today’s blog I would like to summarize what I have written over the last year. In case you are wondering, the most widely read entry was “Well Graded Aggregates vs. Gap Graded Aggregates” with over 1300 pageviews in the last year. After that we have “The 0.26 w/c Myth-Conception” and “Missed It by That Much – Concrete Tests and f’c”. I guess I need to do more articles on concrete mix design. Continue reading
Avoiding Trouble: Efficiently Scheduling Multiple Plants
When visiting a dispatch office, I am often proudly shown a scheduling screen showing the entire fleet on one page. Customer Service Representatives (CSRs) are referring to this total to determine when to accept orders. Unfortunately this produces reduced volume per driver hour, as trucks are sent all over the city to service orders. Plants are often overbooked, creating long queues for loading. Lack of plant detail discourages in-depth analysis and promotes generalizations.
Schedule of a single plant with a fairly flat demand graph
Think Pink for Concrete
Many of you are probably already aware of the Concrete Cares campaign started by Mike Murray. www.concretecares.com So far this group has concentrated on raising awareness about breast cancer more than fund raising to fight the disease, but that is fine by me. It is good that “manly” professions, like plumbers, HVAC people, electricians and now concrete producers are recognizing the need for EVERYONE pitching in and not just women. After all, not only are men affected by loved ones developing the disease, but over 2,000 men were diagnosed with breast cancer in 2012 (compared to almost 230,000 women). Over 400 men and almost 40,000 women died from the disease last year. Altogether, almost 600,000 people in the U.S. died from various forms of cancer last year. http://onlinelibrary.wiley.com/doi/10.3322/caac.20138/pdf
The good news is that we are winning the war on cancer. Since the early 1990s, deaths due to cancer have declined each year. Since 1993 it is estimated that over 1,000,000 people who would normally have died are still alive due to improved cancer treatments. That is something to be proud of.
Part of Concrete Cares’ plan is to have each locale create a unifying project demonstrating the concrete industry’s support for the fight against breast cancer. This could be a decorative pavement, concrete countertop or some other element that can act as a rally point for the fight.
Concrete Cares recently announced their 2013 goal is to have the entire concrete industry show their support for cancer research and treatment by placing a pink ribbon on their work and personal vehicles on October 1, 2013. October is National Breast Cancer Awareness Month.
http://www.concretecares.com/wp-content/uploads/2013/03/October12013.pdf
After all, it is the least we can do… Shouldn’t we be doing more?
Jay
Performance Concrete at a Crossroads
Back in October I published a blog entry entitled “Let the Bakers Bake”. http://www.commandalkonconnect.com/2012/10/08/let-the-bakers-bake/ In it I declared my support for performance concrete specifications and production. I also supported the Australian and European approach that makes the concrete producer responsible for conformance testing of concrete, with confirmation testing being performed by the Owner/Customer. I created a LinkedIn group called “Let the Bakers Bake” and posted a survey asking if concrete producers wanted to do their own testing. 72% of those who responded said “Yes”. You can see the survey at http://www.linkedin.com/groups/Concrete-producers-in-US-should-4662586.S.173044207?qid=7fd1692e-89f9-4dfe-9e22-2d35032ed3a7&trk=group_most_recent_rich-0-b-ttl&goback=%2Egmr_4662586
However, there was a significant group of Producers that said they didn’t want to get into the testing business. I admit that I didn’t specify that Producers could hire this function out to an independent lab, but I think there was more concern than just their capability to perform tests. However, I think that any concrete producer making more than 100,000 cubic yards a year should be able to afford the investment in equipment and personnel to allow them to test most compression cylinders. Continue reading