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Pavement Engineering & ConsultingComprehensive Expert ServicesProper 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. Non-Destructive Testing 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. QA/QC and Plant Inspection Our professionals observe and test sub-grade preparation, installation of sub-grade drainage systems, placement and compaction of aggregate base course, placement and compaction of bituminous materials, and concrete materials. We offer plant inspection, including calibration of the plant and testing of stockpiled material prior to the start of production. We monitor material handling procedures, mix proportions, mixing temperatures and mixing time during production, and sample the final mixtures to ensure conformance with project requirements and approved mix designs. Laboratory Materials Testing Our fully equipped geotechnical and construction materials testing laboratories participate in the AASHTO Materials Reference Laboratory and Cement and Concrete Reference Laboratory (CCRL) programs. |