KPI Survey Highlights
February 25, 2013
I have now closed out my Concrete QC KPI (Key Performance Indicators) survey and below are some of the highlights from the survey. Many thanks to all who entered. I should have another survey up and running soon.
Out of the 70 people who answered the survey, 30% either didn’t know what a KPI was, or didn’t use KPIs. The majority of those who didn’t use KPIs were smaller U.S. companies, but even some international and moderately large companies either didn’t know about them or didn’t use them. I think the number of people who don’t use KPIs is higher, since my Mix Design Methods Survey had 130 respondents and this one only had 70. I imagine that those who didn’t understand KPIs didn’t respond. For those who don’t know what a KPI is, it is an attempt to distill significant information down to a single number, which shows whether things are improving or not. Just as “miles per gallon” (“kilometers per liter”) in a car is a KPI, “psi per lb. of cementitious material” is a KPI. Most of the questions in the survey were only answered by the 50 people who used KPIs.
Only about 30% of the companies responding considered the number of tests run on aggregates as a KPI. Of more interest was that if a company had the ability to test gradations in-house, they ran gradations more often than companies who didn’t have that ability received the information from their suppliers. In-house testing was done either daily, bi-weekly, weekly or monthly. Companies receiving the information from a material supplier or outside lab were more likely to get the information weekly, monthly or less often. I assume that companies that invested in in-house testing valued that information more than companies that didn’t invest in in-house testing.
Very few companies ran tests on cement or pozzolans.
When asked whether they monitored a standard mix as an indicator of overall concrete quality, about 60% of the international companies ran the mix either daily or weekly. About 50% of the U.S. companies ran the standard mix weekly or more often, while 30% ran such a mix monthly.
About ½ of the U.S. respondents said they keep track of the frequency with which each mix is tested, but about 70% of international respondents did. I was pleased to see that 30-50% of the companies reporting even tracked residential concrete mixes.
85% of U.S. companies reported that they tracked production batching tolerances, either on a regular basis or on an as-requested basis. 90% of international companies tracked production tolerances.
What KPIs did people primarily track? Here they are, in descending order of use:
-
78.6% - Standard deviation by mix design
-
73.8% - PSI per mix
-
59.5% - Yield per concrete mix
-
50% - Quantity of rejected concrete
-
50% - Production batching tolerances per plant and material
-
47.6% - Cement efficiency (PSI/lb or MPa/kg)
-
47.6% - Number of low breaks per mix
-
45.2% - Standard deviation per plant
-
42.9% - Strength exceeding target strength
Other KPIs used less often include:
-
Standard deviation per project
-
Number of marginal breaks (close to f’c)
-
Cost of the QC department
-
Within test coefficient of variation by lab or technician
-
Standard deviation of slump
-
Standard deviation of unit weight
-
Standard deviation of air content
Finally, some of the international companies had gigantic QC staffs. I assume these are primarily in countries with low cost labor. The average U.S. concrete producer had 4 technicians and 1 manager on hand.
I’ll probably announce another survey soon, but I haven’t decided on a topic yet. If you have any idea, let me know.
On a totally separate topic, Concrete Producer magazine published my article, “Profiting from Quality Concrete” in their Jan/Feb 2013 issue. You can read it at https://www.concreteconstruction.net/concrete-production-precast/profiting-from-quality-concrete_o
Also, Concrete Producer published another article I wrote, “The Perils of KPI Abuse” in their Web Exclusive section last week. You can read that article at https://www.concreteconstruction.net/concrete-production-precast/the-perils-of-kpi-abuse_o
Finally, last week I conducted a seminar on “QC as a Profit Center” in Orlando, FL. Thanks to all who attended.
[Ed. Note – You might want to check out my webinar, “Concrete Success: Profiting from Quality Control”
