A More Efficient Material Transfer

What states require of MTVs and MTDs

In the market for an MTV or MTD? You better check your state paving specifications first. Some states leave it up to the contractor with end-product specifications, whereas other states mandate the specific type of transfer equipment allowed on the job. Here's a sample of what some state specifications mention relating to material transfering.

Arizona (2001): The state uses an end-product specification (sections 406 and 416). It's up to the contractor to determine the best method for completing the work.

Arkansas (2003): The state requires the use of an MTV or MTD on all State, U.S. and Interstate Highways using more than 1,000 tons of mix. Contractors are to avoid stop-and-go paving, and the material transfer equipment must continuously reblend the mix either in the transfer vehicle, in a paver hopper insert or in the paver's hopper. Temperature differentials of the profile segments cannot exceed 10 degrees F (6 degrees C).

California (2002): Windrow paving is allowed, with provisions, to provide continuous paving, but material in the windrow cannot fall below 260 degrees Fahrenheit (125 degrees Celsius). Pavers shall be operated to ensure continuous and uniform movement of the paver.

Colorado (1999): Stop-and-go operations of the paver shall be avoided, and forward paver speed is to remain consistent to provide uniform and continuous laying of mix. Material is to be transported and placed on the road without segregation.

Florida (2004/05): The specifications require the speed of the paver to be based on the rate of material delivery as long as the rollers are able to compact to spec densities. Equipment selection is up to the contractor. There is also a special provision for the use of experimental machinery to encourage the development and use of new or improved equipment.

Georgia (2001): MTVs are required on state jobs when the ADT is greater than 6,000, of more than 3,000 linear feet and where tonnages are greater than 2,000 tons. The vehicle must receive mix from hauling equipment and independently deliver the mix to the paver. It must have reblending capability to provide a homogeneous, non-segregated mix with uniform temperatures no more than 20 degrees F (11.1 degrees C) between the high and low temperatures measured transversely across the mat. The MTV has to be empty when crossing a bridge and must cross in the travel lane. The paver must have a hopper insert with a minimum of a 14-ton capacity.

Illinois (2003/06): There are no special provisions outlined for MTVs or MTDs in the state's 406 standards and specifications. However, there is a "Special Provision" written for all interstate bituminous paving contracts and other contracts at the District's discretion. This provision requires the transfer equipment to have a minimum surge capacity of 13.5 metric tons (15 tons), be self-propelled and is capable of moving independent of the paver. Additionally it is to have remixing capabilities and be used in conjunction with a paver equipped with a hopper insert with a minimum 12.7 metric-ton (14-ton) capacity. The Bureau of Bridges and Structures must analyze the structures the transfer equipment will cross, and it must be moved across bridges empty.

Iowa (2002): The use of an MTV is subject to approval by the engineer, based on bridge and paving structural evaluation of resultant axle and wheel loads. If using a windrow process, the windrow must be uniform and extend no more than two truck dumps ahead of the paver.

Louisiana (2000): State specifications require continuous plant and roadway operations. An MTV is required on the final two lifts, regardless of average daily traffic, with one truck waiting while the other is depositing material into the MTV to maintain continuous paving. The MTV must have additional mixing capabilities to reduce segregation and a swivel conveyor. The paver must also be equipped with a hopper insert with a minimum of 18-ton capacity.

Ohio (2000): The specs stipulate the coordination of the spreading operation with the rate of production and material delivery to attain uniform, continuous paving progress. There are no special provisions for or against the use of MTVs or MTDs.

Oklahoma (1999 with June OK contractor source): The specs call for the paver to operate at a uniform speed with no consistent stopping between truck exchanges. They allow the use of material transfer equipment unless shown differently on the plans. Windrow paving is not allowed with SMA mixes, only MTV or Mat Smoothness machines can be used. SMA mixes shall be continuously remixed or reblended either internally in the transfer device, in a paver hopper insert or in the paver's hopper.

New York (2002): There are no provisions mentioned for or against the use of MTVs and MTDs.

Texas (2004): All three types of material transfer equipment are allowed unless otherwise shown on plans, provided the equipment ensures a continuous, uniform mix flow to the paver. A specific type of transfer equipment may be required by the plans. The specs also mention that there is to be no bouncing or jarring of the paver.

Source: FHWA website for National Highway Specifications and individual state D.O.T. websites.