Every load of concrete comes with a concrete batch ticket. Here’s what to look for to understand what’s in your concrete at the time of batching.
Let’s start with this example ticket. Since there is no required format, tickets may contain more or less information.
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Tickets show basic information about the purchase, such truck number, ticket number, batch time and date, mix design identity, customer, and job location.
Some tickets show batch weights. Concrete producers invest significantly to create proprietary mixture proportions, so they may choose to not provide batch weights. This ticket shows the design quantity of each material based on saturated surface dry aggregates (SSD), followed by the amount required for 10 yd3 based on aggregates in their actual moisture condition.
Most batch software programs, including the one used here, use apparent aggregate moisture content (total moisture minus absorption capacity), which is simpler but less accurate than using the total moisture content. In most cases, the error is inconsequential. In this case, the aggregates have greater moisture than the SSD condition, so the amount batched must be increased.
The required water content is reduced by all other sources of water; that is, the free moisture in the aggregates as batched, the water estimated to be remaining in the drum before loading, and the amount of water trimmed by the batch operator. Note that water can be shown in gallons or pounds depending on whether it is measured by volume or weight. In this load, only 64% of the design water was added directly in the batch plant.
The actual amount batched varied slightly from the required quantity. This can occur, for example, due to aggregate bin gates or water valves closing too soon or late.
The amount of water is summarized at the end. In this case, 30.9 gal of water was not added at batching and is available to be added on the truck. This water is available intentionally to account for slump loss to the jobsite.
Verifi interfaces with the batch software to obtain the actual amount of water batched and the amount remaining to be added after batching. Verifi can automatically add this water to maintain the target slump in transit. By using this number, Verifi can ensure the maximum design water content is not exceeded.