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Cement Mixers – Week 1

Groundhog’s Day means nothing. Any seasoned truck enforcement officer recognizes that an increase of cement mixers on the street means the weather is starting to turn for the better.  It’s not that cement can’t be poured in the cold, but warm weather is the ideal…who wants to float concrete in the January?  Cement mixers also signal the start of the construction industry and hopefully 2013 will be a good year.  The economy needs it.  So as the birds begin chirping and the cement mixers start spinning, it is time to talk about laws specific to those vehicles.

The first thing to understand is that concrete is the foundation (pun intended) of the construction industry.  Because of that, concrete industry has a strong lobby in Springfield.  And because the industry has a strong lobby, they have a lot of exceptions to the law.  And because they have a lot of exceptions, there is inherently confusion.

In Illinois, the most common configuration is the 4-axle mixer, either front or rear discharge.  There are fleets which run 3 or 5-axle mixers as well, but they are for sure in the minority compared to the sheer quantity of 4-axle mixers.  At this time, the 4-axle mixers are the only configuration which receives any special weight exemptions.

The ITEA heavily promotes a policy that overweight violations in Chapter 15 of the Illinois Vehicle Code are mutually exclusive from overweight violations in Chapter 3 of the IVC.  But in all things truck law, there are exceptions.  Typically, any 4-axle truck is limited to the maximum weights listed in Chapter 15 like any other truck.  However, when the owner of the truck pays an extra $125 with the registration to be a Special Hauling Vehicle (SHV), those weights change.

As it pertains to cement mixers, single axle and tandem axle weights remain the same (20,000 and 34,000 respectively), and the entire gross weight from axles 1-4 are still subject to the federal bridge formula.  The SHV permit protects the mixer from the police using the federal bridge formula to find an overweight violation from any group of 3-axles, whether from axles 1-3 or from axles 2-4. It is those groups of axles where cement mixers commonly exceed legal weights.

The SHV also allows a cement mixer with a tandem spread between six feet (72”) and eight feet (96”) to be allowed 36,000 pounds instead of the maximum 34,000 pounds for tandems. All these special exemptions are predicated on the fact that the mixer is carrying wet concrete in the plastic state.  Not sand, not water.  Also, these exemptions are not extended to the truck when operated on defense highways (interstates and toll roads) in Illinois.

The confusion arises when a 3-axle mixer or a 5-axle mixer is stopped by the police. Even if one of these vehicles is registered with an SHV, there are no special weight exemptions.  If a 5-axle mixer is operating with 4-axles on the ground, then the SHV applies.  If a 4-axle mixer with an SHV is only operating with 3-axles on the ground, then the SHV does not apply.  How many physical axles are attached to the truck is not the question that needs to be answered.  How many axles are on the ground is the criterion used to determine whether or not the SHV, and all the special weight exemptions, are in play.

Don’t get too comfortable in your understanding of this law yet.  The Illinois General Assembly is considering a bill (HB2361) to allow some weight exemptions for 3-axle mixers registered as an SHV.  The ITEA will keep you posted if and when this bill is ratified.

Next week, this blog will look at the proper methods for weighing a cement mixer, weight tolerances and what licenses are need to operate them.

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