Transportation Structures


Since ancient times bridges have been utilized to reduce time of passage connecting two distant points. With the increasing demands of transportation, bridge design has advanced immensely.

With modern engineering techniques and advances in building materials, todays bridges have evolved into unique wonders. As the world’s population increases exponentially transportation agencies are faced with challenges to improve the safe movement through their communities. This comes with challenges including longevity of structures, planning to finance, and construction of the structure.

HBM knowledge extends from bridge design, construction, preservation, and with safety challenges always being a priority. We have demonstrated our continued leadership by applying our thorough approach to any design challenge. We’ve partnered with clients on a wide-range of bridge types: from simple to major river-bridges, movable bridges, concrete box, girder, truss, arch, and cable-stayed structures.


Through the advancements of hydraulics in the past century, culverts have become an essential to roadway transportation. They server as cross-drains relief by passing water under roadway at natural drainage and stream crossings or as pedestrian crossings or animal crossings under roadway.
Environmental impacts are a priority when it comes culvert design. Safe and stable stream crossings need to accommodate wildlife and protect stream flow while reducing structural damage from erosion.

During new or replacement of culverts, techniques are used to have minimal impacts on both the environment and transportation. This includes having short term impacts on the aquatic biology and prevention of energy loss of the water flow.

HBM’s expertise…..

Retaining Walls

With increases in infrastructure development and rehabilitation the need to replace or construct new retaining walls is key to maintaining current ground conditions. Retaining walls have multipurpose functions that include providing functional support, improve site drainage, and aesthetic purposes.
Designing a retaining wall many factors are considered in the design process especially lateral earth pressures and hydrostatic pressures. HBM takes into consideration materials required, type of wall, construction process, drainage, foundations, variance, and anchoring. to come up with the perfect design

Ancillary Sign and Signal Structures

As the application of ITS technologies is emerging nationally, concerns over the safety of ancillary structures that extend over roadways is a priority. Ancillary sign and signal structures assets include highway signs, luminaires, traffic signals, and bridge mounted signs and utility structures.

With highways extending cross country proper design and maintenance of Overhead Sign Structures (OSS) is important for the safety of the users. Specific Design criteria and maintenance inspection routines is applied at HBM to guarantee no failures occurs.

As highways and roadways are becoming more technologically advanced Dynamic Message Signs (DMS) have become necessary to keep drivers updated with incident management, route diversions, travel times, and other safety related messages. DMS structures requires a safe design and strict maintenance practices. HBM is well versed in the design and maintenance of DMS structures on both highways and local roads.

HBM’s inspection teams have performed inventory and routines inspection including non-destructive testing on hundreds of ancillary structures. These inspected structures range from traffic and high mast poles to sign trusses spanning over multiple land highways. Our engineers and inspectors perform their tasks with conformance with FHWA-NHI standards.