Transportation Market Services
Bridge Engineering Services
NTH provides clients with expertise in both design and inspection services and have abundant knowledge of bridge deterioration trends, fracture critical inspection and fatigue prone detail identification as well as high level exposure to ABC and alternative installation and repair techniques.
During site investigations, NTH sounds concrete elements and conducts visual inspections of deck undersides, substructure units for indications of movement, and bridge railings and pedestrian fencing for damage. NTH also conducts underwater inspections of bridge foundations.
NTH performs regular bi-annual and beam end inspections as well as element specific investigation.
NTH has been involved in the design and construction monitoring of numerous rehabilitation projects that involve application of construction materials to extend the life of a structure. Some of these include concrete decks for parking structures, concrete basin floors and walls (crack injections and spalling repairs), shotcreting of concrete tunnel liners, structural steel modifications for buildings and others.
Pavement Engineering & Consulting
Proper design and maintenance of pavement are necessary for safety and optimal use. NTH provides a wide range of pavement engineering services.
Pavement Investigation and Evaluation Services
NTH professionals perform network and project level analyses that include a visual condition survey of all paved surfaces as well as drainage and sub-structures to determine the types, extent and severity of observed distress. We analyze the data to determine pavement network needs, project priority, optimum strategies, and rehabilitation/restoration alternatives, as well as to perform cost/benefit analysis.
NTH supplements field sampling, testing and visual condition surveys with nondestructive testing, such as dynamic deflection testing, ultrasonic testing, nuclear density testing and ground penetrating radar. We perform subsurface investigations to gather additional information using pavement cores to obtain existing cross-sections, soil test borings to obtain samples of base, sub-base and sub-grade layers, laboratory testing to determine soil characteristics and engineering properties, and dynamic deflection testing to provide a quantitative measure of the structural capacity.
Structural Pavement Design
NTH professionals create a structural pavement design that defines the type and thickness of pavement cross-sections based on an evaluation of sub-grade conditions, drainage, environmental factors, traffic loads, traffic patterns, desired service life and material availability.
Our clients call on us because we have trained and experienced personnel in the area of geotechnical engineering, engineering geology, hydrogeology, and soil mechanics.
NTH takes great pride in our geotechnical engineering abilities. We understand the criticality of obtaining and making effective use of reliable and accurate subsurface data. NTH provides engineering services for transportation facilities such as highways, bridges, local roads, culverts, and auxiliary structures, such as overhead signs, intelligent transportation system infrastructure, and traffic signals. We have also provided geotechnical engineering services for airports, rail and light rail systems, and marine and docking facilities.
Subsurface Utility Engineering
NTH professionals are adept at performing SUE services. Working in conjunction with project design personnel, we accurately locate existing utilities and identify areas of potential conflict well in advance of final design and the distribution of construction bid documents.