Expert Details

Expert in Asphalt Materials, Paving, Pavements, Roads, Roofing, Ports, Airports, and Rheology

Expert ID: 729364 Pennsylvania, USA

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Expert has a unique combination of experience that includes working with a major contractor for 10 years, university appointments and consulting for over 20 years. Expert is a member of numerous expert task groups that further promoting the development of performance based specification for pavement materials. Expert is a professional engineer (P.E.) in the U.S. (registered in multiple states) and is a Chartered Engineer (C.Eng.) in the United Kingdom.

His work in pavement design for ports and airports has been applied in five continents around the world. He is engaged in specialized site and laboratory investigations of asphalt and asphaltic concrete materials, reporting on pavement failures, as well as analysis and design of overlay and reconstruction measures for projects in the USA, Europe, Asia, South America, Canada and Australia. Expert has numerous peer review and conference publications since the late 1980's.

Expert’s work involves the implementation of material quality at many major sites and he is instrumental in the training of staff for this function. Expert supervises several key paving projects every year involving important structures such as those built on environmentally sensitive sites and important bridge structures.
Expert leads several research efforts in rheology and the determination of the physical properties asphalt (including those with polymer and other modifications) with funding from industry and government sources. The pioneering technology developed by Expert is in use in over 20 countries by over 200 pavement and materials engineers. Expert’s work in the area of cold temperature cracking has resulted in him being regarded as one of the leading experts in world in this field. The software developed by his team for determination of the critical cracking temperature associated with single event low temperature thermal cracking is described in AASHTO PP-42 and is implemented in the AASHTO M320 Table 2 standard for asphalt binders. Expert fatigue methods for materials have recently been included in ASTM standard D7460. He has led the development of approximately 20 software packages for pavement engineering of which eight are marketed and used in approximately 40 countries around the world. The technology includes pavement structural design, analysis of FWD data, materials property analysis and rheology.
Expert’s work includes many environmental uses of asphalt. For example many sites have been constructed that involve supplying materials to effect land closures in compliance with strict U.S. EPA requirements. In addition, studies have involved assessment of noise produced by different pavement materials, uses of material in bio-risk areas, assessment of potential of asphalt materials for nuclear containment, etc. Expert is responsible for the operation and pavement evaluations conducted with the companies Falling Weight Deflectometer. Projects are mainly concentrated in the U.S., UK and the Caribbean.

Expert has led the development of approximately 20 software packages for pavement engineering of which eight are marketed and used in approximately 40 countries around the world. The technology includes pavement structural design, analysis of FWD data, materials property analysis and rheology.

Expert may consult nationally and internationally, and is also local to the following cities: New York, New York - Yonkers, New York - Newark, New Jersey - Jersey City, New Jersey - Paterson, New Jersey - Elizabeth, New Jersey - Trenton, New Jersey - Philadelphia, Pennsylvania - Allentown, Pennsylvania - Stamford, Connecticut

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Year Degree Subject Institution
Year: 1996 Degree: Ph.D. Subject: Civil Engineering Institution: University of Nottingham
Year: 1985 Degree: B.Sc.(Hons) Subject: Civil Engineering Institution: Nottingham Trent University

Work History

Years Employer Title Department Responsibilities
Years: 1997 to Present Employer: Undisclosed Title: President Department: President Responsibilities: Expert leads a team of geotechnical, civil, structural and environmental engineers with projects in 5-continents coving all aspects of civil engineering. In addition, he provides a specialized consultancy service to advise on engineering and contractual problems related to the design, construction and maintenance of highway, airfield and port pavements. Responsible for the planning and execution of many projects involving failure investigations, pavement management, evaluation and design, and advice on the use of novel materials and problems arising during construction.

Within his firm, he is responsible for the technical direction of the company in the areas of pavements, materials and software. The firm has developed several pieces of analysis software, in particular TSAR™ (low temperature crack prediction) and RHEA™ (rheology analysis) have been widely adopted and also marketed with equipment manufactures.

Expert is currently responsible for the day-to-day operations of the company.
Years: 1993 to 1997 Employer: SWK Pavement Engineering Title: Technical Vice President Department: Responsibilities: He was responsible for the development of procedures for the testing and evaluation of asphaltic binders and mix properties to determine their suitability for use in pavement structures. He provided overall technical direction on the interpretation of the SHRP specifications. In addition, he provided technical leadership in a contract with the UK Department of Transport on the development of a Performance Related Specifications for Modified Binders in the United Kingdom. This work involved the adoption of both European and USA procedures for measuring binder and mixture performance. He was also responsible for the day to day provision of testing services by SWK (PE) in the North East USA.
Years: 1988 to 1993 Employer: SWK Pavement Engineering Title: Senior Pavement Engineer Department: Responsibilities: Management of $1 million research contract into the properties of asphaltic materials as part of the USA Strategic Highway Research Program. Tests developed from this research have become new AASHTO test methods. The work included a large amount of Fatigue, Deformation and Water Damage Testing. Also, the work involved the development of computer programs to control servo-hydraulic and electro-magnetic fatigue testing devices written in BASIC and PASCAL programming languages respectively. Data reduction and analysis also involved development of several computer programs written in PASCAL and FORTRAN.

In addition research work into finite element pavement modeling and pavement design has been carried out for TRRL and Oil Companies. This work resulted in the development of, first a viscous pavement design method to predict pavement deformation using layered viscous theory for the UK DOT which was considered a development of the procedures contained in the Shell Pavement Design Manual. This viscous analysis method has been in routine use by SWK(PE) since 1990 and has also been used to assess specification limits for deformation performance related tests. This work was followed by a fully visco-elastic pavement analysis software package (PACETM) that uses a sophisticated finite element model (similar in many respects to that in SuperpaveTM software) and includes associated material models.

Call of consultant to the Transport Research Laboratory advising on the visco-elastic properties of bituminous produces used in bridge deck joints and associated test methods and methods of analysis.

Developed and managed SWK(PE)'s laboratory which was specifically organized to implement performance based testing in a commercial environment. In addition he was responsible for the organization of many laboratory-based courses in order to educate engineers and transfer new technologies into the highway industry. He was also involved in lecturing on fundamental aspects of material behavior on the University of Nottingham MSc course in Highway Engineering.

Worked as a materials consultant (1988-89) on IRDB (World Bank) and two ADB (Asian Development Bank) road contracts in Sri Lanka. This work involved approval of mix design, selection of materials and pavement design. In addition, two days of lectures were given to engineers from the Highways Department in Sri Lanka.
Years: 1986 to 1988 Employer: University of Nottingham Title: Teaching Company Assocaite Department: Responsibilities: Evaluation of suitable surfacing for high stress and special applications at roundabouts, bridge approaches, race tracks, etc. Materials used in these locations included pigmented Mastic Asphalt and Grouted Macadam. Development of design methods for asphalt with various modifiers including construction and monitoring of several trial pavements and production of technical manuals for clients. Provided advice to many clients concerning arbitration/litigation on construction problems involving asphaltic materials.

Conducted research work into suitability of pavement materials in Dubai, involving laboratory testing to determine mix properties, such as elastic stiffness and creep, in conjunction with Nottingham University to determine a pavement design method for Dubai. Engaged on specialized asphaltic materials investigations involving Infra-Red Spectroscopy (IR) and Gas Liquid Chromatography (GLC). Design of overlays for road projects in Malaysia involving interpretation of site investigation information including Roadrator surveys. A novel technique, Geogrid reinforcement, was used for the Jalan Vantoren Highway. Detailed study into effect of cold weather conditions and materials on durability of road pavement in Bedford.

Falling Weight Deflectometer surveys have been undertaken on a number of sites in England. These include sites in Nottinghamshire, Bedfordshire, Northamptonshire and Yorkshire. In Yorkshire the survey on the A64 was combined with a Deflectograph.

Development of a procedure to assess asphalt overlaid concrete pavement structures (Hedon Road in Hull) which involved the development of computer programs to analyze and plot data in various forms resulting in a method to assess joint and pavement performance.
Years: 1986 to 1986 Employer: Essex County Council Title: Engineer Department: Responsibilities: He worked on the design of the Braintree By-Pass using MOSS Computer aided designs system and preparing highway alignments for the Little Clacton By-Pass in preparation for a public enquiry.
Years: 1980 to 1985 Employer: Tarmac Roadstone (Southern) Ltd. Title: Technical Officer Department: Responsibilities: Responsible for quarry products and technical site supervision of major road contracts in East Anglia, training of technicians and production of technical reports. During this period there was involvement in five coating plants and six aggregate supply sources. A short period was also spent running the central laboratory for the company, working with Marshall Asphalt design and overseeing its use on airfield contracts. Within this period a degree was obtained at Nottingham.
Years: 1976 to 1980 Employer: Tarmac Roadstone (Southern) Ltd. Title: Technician Department: Responsibilities: Responsible for quality control of all quarry products including asphaltic materials, concrete and aggregates. Worked with many types of asphalt plants, stone processing and Portland cement concrete production facilities. Also responsible for specialized materials including "Marine Mastics" supplied to Europe, Middle East, Far East and South America. Work also involved running quarries and other operations associated with a major quarrying company.

Career Accomplishments

Associations / Societies
Member - American Society of Highway Engineers (USA);
Member - Association of Asphalt Paving Technologists (USA);
Member - ASTM (USA);
Member - The Institute of Materials, Minerals and Mining (MIMMM) (UK);
Member - Institute of Asphalt Technology (MIAT) (UK);
Member - New Jersey Society of Asphalt Technologists (USA);
Member - Institution of Highways and Transportation (MIHT) (UK);
Member - Canadian Technical Asphalt Association (Canada);
Member - RILEM (International Union of Laboratories and Experts in Construction Materials, Systems and Structures);
Member - Society of Rheology;
Member - International Society of Asphalt Pavements (ISAP);
Member - American Concrete Institute (USA) (1993 to 2006).
Licenses / Certifications
Professional Engineer (PE) - New Jersey, 1997 (GE 40815), Florida, 2000 (56312), Pennsylvania, 2002 (PE061313);
Charted Engineer (CEng) - United Kingdom, 1997 (502513).
Professional Appointments
TRB Expert Task Group on Superpave Binder Technology (2002-2006), (2008-present);
ISAP - Technical Committee on Constitutive Modeling of Asphaltic Materials, WG07: on Bitumen and Mastics (2007-Present);
Fatigue and thermal cracking working subgroup of binder ETG (1998-2006);
TRB AFK20 – Committee on Characteristics of Asphalt Materials Committee;
TRB A2B03 – Committee on Flexible Pavement Design (1998-2002);
TRB A2D04 – Committee on Characteristics of Bituminous Paving Mixtures to Meet Structural Requirements (1998-2002);
FHWA Accelerated Pavement Testing, Expert Task Group (1998);
FHWA Advisory Panel on Western Research Institute, Fundamental Properties of Asphalts and Modified Asphalts (1996-2006);
2000 – Present, Associate Engineer, PRI Testing Laboratories, Tampa, Florida, USA;
2001 – 2006, Professor (adjunct), Department of Civil Engineering, University of Calgary, Alberta, Canada;
2001 – 2002, Managing Editor - International Journal of Pavement Engineering and Asphalt Technology (IJPEAT).
Publications and Patents Summary
He currently has two patents pending associated with materials developments for road, ports and bridge applications.

Publications: include over 50 papers in varrious journals, conference proceedings and research records.

Additional Experience

Expert Witness Experience
He has extensive expert witness work - some examples as follows:

North America projects have included; 1) assessment of distress in asphalt pavement, (Pennsylvania) for a Hot-mix producer. Early failure was blamed on hot-mix quality whereas failure occurred due to inadequate compaction by lay-down contractor; 2) Car parking and storage yard, New Jersey for the facility owner with issues concerning the durability and quality of asphalt pavement, advice given on suitable remedial measures; 3) Claim for excess quantities of materials, New Mexico Design working with the design consultant, advice was given with regard to type of operations by contractor resulted in excess usage of materials. Advice was given to client on reasonable methods of construction (client won case in court); 4) Deformation of boat-yard pavement, Florida for design consultant (settled in arbitration) involved a finite element analysis suggested that the variable soil compaction properties resulted in excessive deformation of the pavement structure; 5) Failure of interstate highway he acted for a bonding company giving detailed pavement investigation and assessment of cause of failure.

South America projects have included; 1) Surface-dressing of parking areas in Guyana were the Contractor had an ambiguous design specification resulted in clients objectives not being met during the construction works.

Europe projects have included; 1) Distress on DBFO Contract in Scotland working with a Design-Build Consortium which eventually settled out of court, problems occurred with various aspects of construction. Work was conducted to assess how failure was related to construction and design issues and appropriate advice given; 2) Disintegration of road surface, England for a road authority - a road surface had disintegrated – an investigation concluded that the asphalt materials were susceptible to stripping and failure due to freeze thaw action; 3) Failure of surfacing on velodrome, England working for the owner of facility - problem with compaction and over-fluxing of asphalt materials use on banking. Laboratory work conducted to assess these facts and advice given to owner on remedial works and claims against original contractor; 4) Friction course failure, England which was blamed on the bitumen modifier when the data really showed that inadequate compaction was most likely cause of failure; 5) Skidding accident – country road, England, working for a private individual, problem occurred on corner were the road owner has changed the surfacing type without consideration of the different frictional properties of the materials.

Asia projects have included; 1) Thermal cracking, Kazakhstan working for the contractor, advice was given with respect to thermal crack formation in asphalt roads and the effect of binder choice; 2) Early life pavement failures, Philippines working for the Toll Road Owner (case settled out of court), a detailed investigation of multiple early life failure of asphalt pavements and overlays was conducted.
Training / Seminars
Present RHEOBIT workshops - this course is taught on an approx yearly basis. In 2011 this will be delivered with the Asphalt Institute in a number of locations.

Expert teaches other courses on asphalt materials from time to time.
Vendor Selection
As necessary - suppliers for associated testing are obtained through numerous contacts in industry.

Fields of Expertise

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