American offers a range of services that includes all the structural design capabilities that are needed to support any contract.
Our structural design capabilities include:
- Retaining wall structures
- Box culverts
- Load ratings
- Overpass structures
- Bridges over waterways
- Overhead sign support
- Mast arm signal supports
- Strain poles
- Sound barrier walls
- Timber structures
Load Rating Analysis
American specializes in bridge load ratings for structures ranging from simple span PPC beam bridges to complex long span steel truss and cable supported bridges. In addition to load rating new or existing bridges, we have developed load ratings for numerous other structures including timber bridges, simple reinforced concrete bridges, prestressed concrete bridges, steel plate and box girder bridges, post tensioned segmental concrete box girder bridges, and steel truss bridges. We use the latest bridge analysis and design software, guided by extensive experience and engineering judgment, to develop comprehensive evaluations and safe load ratings for each bridge.
Scour Analysis / Hydraulic and Hydrological Studies
American’s hydraulic modeling capabilities range from simple one-dimensional modeling to complex two-dimensional models. One dimensional modeling is often sufficient for a bridge hydraulics evaluation and is performed with United States Army Corps of Engineers (USACE) Hydraulic Engineering Center’s River Analysis System (HEC-RAS) software. Two-dimensional modeling produces more reliable results in instances where flow conditions and boundary conditions are more complex, but has greater data requirements and requires more time to develop the model. When two-dimensional modeling is needed, American utilizes state of the art software such as USACE Coastal and Hydraulics Laboratory’s Adaptive Hydraulics (AdH) Modeling System to analyze flow conditions and design flood stages. Utilizing the hydraulic model, bridge scour is evaluated in accordance with procedures outlined by the Federal Highway Administration (FHWA) Hydraulic Engineering Circular No. 18 and as refined by other studies and publications. The design scour is determined through either utilizing sediment transport modeling options within the modeling system or by utilizing the results of the modeling with scour equations. The hydraulic evaluation ensures that adequate hydraulic capacity is provided through the bridge. Scour predictions are utilized for determining appropriate design measures against structural failure.
Bridge Inspection and Evaluation
Drawing on the extensive bridge evaluation experience of American’s structural engineers, we conduct thorough bridge inspections to provide all of the measurements and other information necessary to fully analyze each bridge. Based on this data collected, we conduct a full evaluation of the bridge, based first on safety and capacity and then on durability, remaining life and comparison of replacement and rehabilitation options to assist owners to choose the most appropriate course of action for their needs. American’s structural engineers have conducted full scale investigations and evaluations of timber bridges, simple reinforced concrete bridges, prestressed concrete bridges, steel plate and box girder bridges, post-tensioned segmental concrete box girder bridges, steel truss bridges and others.