Example of an HS truck loading: HS20-44 indicates a vehicle with a front tractor axle weighing 4 tons, a rear tractor axle weighing 16 tons, and a semi- trailer axle weighing 16 tons. The H and HS vehicles do not represent actual vehicles, but can be considered as “umbrella” loads.
What is h15 loading?
Most bridges in the United States were designed to accommodate either an H-15 or HS-20 loading. An H-15 loading is represented by a two-axle single unit truck weighing 30,000 pounds (15 tons) with 6,000 pounds on its steering axle and 24,000 pounds on its drive axle.
What does H25 pound mean?
An “H20” truck only has one axle under the trailer and a total load of 40,000 pounds. An “H25” or an “HS25” series truck will be almost identical – except the drive axle will be 10,000 pounds and the axle(s) under the trailer will be 40,000 pounds each.
What is the difference between H-20 and HS-20 loading?
What’s the Difference Between H-20 and HS-20? The difference between an H-20 and HS-20 is an H series truck has two loaded axles, one for the drive axle and one for the trailer, and an HS series truck has more than two loaded axles, one for the drive axle and more than one for the trailer.
What is H20 live load?
Live loads are temporary loads that act on a structure. As defined in the AASHTO Standard Specifications for Highway Bridges, the design live load is defined as H20/HS20 truck loading or lane loading using the load that produces the largest moment or shear.
What is Lane load?
Lane loading is referred to as the load, which is used to provide the easier method of computing the shear and moments rather than using the concentrated wheel loads. These loads are used in the design of bridge decks, which consists of several lanes on the multiple spans.
What is H 40 loading?
AASHTO H40 or HS-40 Loading is specified for areas that will be subjected to extremely heavy truck traffic (such as truck stops, fire stations and mining facilities).
What does AASHTO stand for?
American Association of State Highway and Transportation Officials
The American Association of State Highway and Transportation Officials (AASHTO) is a standards setting body which publishes specifications, test protocols, and guidelines that are used in highway design and construction throughout the United States.
What is an H 20 loading?
What does HS-20 traffic rating mean? This is the term used by AASHTO and ACI to describe normal MOVING traffic loading conditions up to 18-wheeler loading. This loading assumes a 16,000 lbs wheel load and therefore a 32,000 lbs axle load.
What is the design lane load?
The design lane load consists of a load of 0.64 klf uniformly distributed in the longitudinal direction. Transversely, the design lane load is assumed to be uniformly distributed over a 10.0-foot width. The force effects from the design lane load are not subject to a dynamic load allowance.
What traffic rating means?
Traffic-Rated: This casting meets the AASHTO M306 proof load, and the loading criterion is 40,000 to 100,000 lbs. This designation is appropriate for traditional traffic loading. • Airport-Rated: This casting can accept loading from 200,000 lbs and up and includes an additional safety factor beyond FAA design loading.
What’s the difference between HS20 and HS25 axles?
Thus, the HS20 axle load of 32,000 pounds becomes an HS25 axle load of 40,000 pounds. The increased load can in some cases create the need for additional reinforcing steel and sometimes a thicker top slab on underground structures installed in areas exposed to heavy truck loads.
How big is an axle on a H25 truck?
An “H25” or an “HS25” series truck will be almost identical – except the drive axle will be 10,000 pounds and the axle (s) under the trailer will be 40,000 pounds each. Figure 1 below illustrates the axle load and spacing breakdown for both HS20 and HS25 design trucks.
How to calculate the tonnage of a HS20 truck?
To determine the total tonnage of the “HS” vehicle you will have to add one additional trailer axle load. An “H20” or an “HS20” series truck will both have an 8,000-pound axle load for the drive axle and a 32,000 pound axle load for the axle (s) under the trailer.
What’s the difference between a HS25 and a hl93?
The HL93 “design tandem” wheel load is 12,500 pounds compared with the “Alternate Military Load” of 12,000 pounds. The extra 500-pound wheel load is not a large increase and will only affect those designs that did not have excess capacity. Designs that were based on HS25 loads can in some cases be capable of carrying the new “design truck” load.