What We Do

Smoothing out a rough ride through pavement research

The ability to forecast pavement condition is highly valuable in supporting pavement management decisions. As engineers, we continually test and research to develop long-lasting, cost-effective pavement solutions.

The single most costly element of a highway system is the pavement structure. The federal government and state highway agencies sponsor pavement research programs in an effort to reduce this cost – and SME plays a pivotal role in research.Our Pavements experts have conducted pavement research for over 20 years. Studies have shown that roughness is one of the biggest concerns of highway users and smoothness is one of the highest priorities. Additionally they have shown that pavements that are built smooth stay smoother longer and provide a longer pavement life. Our professionals have performed research studies related to pavement smoothness, roughness progression in pavements, inlcuding:

Investigation of Development of Pavement Roughness, FHWA Report No. FHWA-RD-97-147
Achieving a High Level of Smoothness in Concrete Pavements Without Sacrificing Long-Term Performance, FHWA Report No. FHWA-HRT-05-068
Quantification of Smoothness Index Differences Related to Long-Term Pavement Performance Equipment Type, FHWA Report No. FHWA-HRT-05-054
Smoothness Criteria for Concrete Pavements, FHWA Contract No. DTFH61-03-C-00105
Smoothness Criteria for Asphalt Concrete Pavements, FHWA Contract No. DTFH61-04-D-00010
LTPP Data Analysis: Factors Affecting Pavement Smoothness, National Cooperative Research Program Project 20-50 (08/13)
Issues in Pavement Smoothness: A Summary Report, National Highway Research Program Project 20-51(01),
Guidelines for Longitudinal Pavement Profile Measurements, National Cooperative Highway Research Program Report 434 (As a subcontractor to University of Michigan)
Relating Ride Quality and Structural Adequacy for Pavement Rehabilitation/Design Decisions, FHWA Report No. FHWA-HRT-12-035 (As subcontractor to Fugro Consultants)

Long Term Pavement Performance

SME has been providing technical assistance to the FHWA’s long-term pavement performance (LTPP) program in the area of smoothness data collection since 1995. The LTPP program collects data at numerous test sections established on in-service roadways in the United States and Canada. Smoothness data collection commenced in 1989, and in 2000 data was collected at over 2,100 test sections. The following are some activities SME has performed for this project:

Developed specifications for purchasing of new smoothness data collection equipment (profilers)
Performed acceptance testing on new equipment that has been purchased to verify they meet the specifications
Developed equipment manuals for data collection
Addressed issues related to data collection and providing solutions
Performed comparisons among the four profilers that are used to collect data for the LTPP program to ensure they collect similar data

Pavement Smoothness

SME has assisted State Highway Agencies (SHA) in implementing American Association of State Transportation and Highway Officials (AASHTO) standards related to pavement smoothness under a FHWA contract since 2004. Our services included:

Performing reference profiler measurements that are needed for certifying inertial profilers
Assisting SHAs with setting-up and conducting programs to certify contractor owned profilers
Reviewing SHA specifications related to pavement smoothness and providing feedback
Reviewing SHA documents related to procuring profilers and providing feedback
Assisting SHAs in trouble shooting equipment problems
Analyzing data collected by inertial profilers to investigate issues related to pavement factors and equipment factors that affect the data collected by inertial profilers

SME has also served on the Expert Task Group and coordinated the update of the following four AASHTO standards related to pavement smoothness:

M 328 – Standard Specification for Inertial Profiler
R54 – Standard Practice for Accepting Pavement Ride Quality When Measured Using Inertial Profiling Systems
R56 – Standard Practice for Certification of Inertial Profiling Systems
R57 – Standard Practice for Operating Inertial Profiling Systems

FWD

SME engineers participated in the development of the course material that was used for a National Highway Institute (NHI) course on Pavement Deflection Analysis (NHI Course No. 13127). SME engineers served as instructors for this course, and taught the course to State Highway Agency (SHA) personnel in several states.