How long should it take? There are different guidelines in establishing concrete delivery intervals.

If you ask 100 different producers what guidelines or rules

For measuring the overall efficiency of a delivery operation, cubic yards delivered per driver hour is still their best measure of efficiency, says Tim Green, ready mix operations manager with Hanson Aggregates in the Phoenix area.

Using information from their Jonel dispatch system and their time clocks, Hanson is able to track yards per hour on a per plant basis and a per driver basis. Using a benchmark of 3.5 yards per hour, Green and his team can quickly pinpoint problem areas as they develop.

When it comes to establishing delivery intervals, Green says they consider many factors--delivery distance, expected loading and washout times, their history with the customer, and yards ordered per hour. Green has nine locations and 12 plants, enabling Hanson to keep delivery distance down and more tightly control delivery schedules.

Truth In scheduling

Stonehenge Concrete & Gravel in Richmond, Ind., continues to struggle with determining optimal delivery intervals. "You always tend to be overoptimistic when scheduling an order," says Matt Jetmore, president of Stonehenge. "For example, when you schedule a bridge pour, you generally think that a bridge deck is going to pour out fast. But you have to remember to factor in testing and other factors that tend to slow you down. We've also found that using five minutes per yard tends not to be a reliable indicator on smaller jobs."

Unlike Hanson in Phoenix, Jetmore's three plants are in smaller, mostly rural markets in eastern Indiana. While delivery areas do have some overlap, Stonehenge doesn't have the flexibility that Hanson has. To counteract this, Stonehenge uses several factors to establish its delivery intervals, including mix, expected average load size, job type, delivery distance, truck availability, and customer history.

Jetmore also finds that the bigger the load, the quicker it pours out. "The bigger loads generally go to customers who are better able to process the load," he says. "The smaller loads may go to homeowners trying to do the job themselves and they aren't able to take the concrete off the truck that quickly."