https://www.coolrooftoolkit.org/wp-content/uploads/2012/04/20120127190624231.pdf

Cool surfaces and shade trees to reduce energy use and improve air quality in urban areas

The high wheel loads of heavy trucks are a major source of pavement damage by causing fatigue, which leads to cracking, and by permanent deformation, which produces rutting. Among heavy trucks, all do not cause equal damage because of differences in wheel loads, number and location of axles, types of suspensions and tires, and other factors. Further, the damage is specific to pavement properties, operating conditions, and environmental factors. The mechanics of truck-pavement interaction were studied to identify relationships between truck properties and damage (fatigue and rutting). Computer models of trucks were used to generate wheel load histories characteristic of the different trucks and operating conditions. Influence functions, obtained from rigid and flexible pavement structural models, were used to predict responses along the pavement resulting from the truck motions. The pavement responses were evaluated to estimate overall pavement damage caused by each truck. The study assessed the significance of truck, tire, pavement, and environmental factors as determinants of pavement damage. Maximum axle load and pavement thickness have the primary influences on fatigue damage. Truck properties, such as number and location of axles, suspension type, and tire type, are important but less significant. High temperatures in flexible pavements and temperature gradients in rigid pavements adversely affect the damage caused by truck wheel loads with a fairly strong interaction. The report discusses and quantifies the influence of these variables.

Effects of heavy-vehicle characteristics on pavement response and performance

This paper describes the quantification of three-dimensional tyre/pavement contact stresses for vehicle tyres. The Vehicle-Road Surface Pressure Transducer Array (VRSPTA) system was developed to measure contact stresses under moving loads, i.e., Stress-In-Motion (SIM). Prediction equations for quantification of these stresses, based on tyre inflation pressure and loads for seven different tyre types, are given. Tyre inflation pressure predominantly controls the vertical contact stresses on the pavement at the tyre centre, whereas the tyre load controls those at the tyre edges. Analysis indicated that during instantaneous overloading/under-inflated conditions the maximum strain energy of distortion (SED) in the asphalt surfacing occurs close to the tyre edges, while under instantaneous uniform vertical stress conditions the SED is within the asphalt surfacing at the tyre centre. In addition to improved load/contact stress idealization for modelling, this finding may have important implications for the design of relatively thin asphalt surfacing layers for pavements.

Determination of pneumatic tyre/pavement interface contact stresses under moving loads and some effects on pavements with thin asphalt surfacing layers

Dynamic effects of moving loads on road pavements: A review

This paper presents a mechanistic approach to uniaxial viscoelastic constitutive modeling of asphalt concrete that accounts for damage evolution under cyclic loading conditions. Schapery's elastic-viscoelastic correspondence principle is applied as a means of separately evaluating viscoelasticity and time-dependent damage growth in asphalt concrete. The time-dependent damage growth in asphalt concrete is modeled by using a damage parameter based on a generalization of microcrack growth law. Internal state variable formulation was used in developing the analytical representation of the model. Tensile uniaxial fatigue tests were performed under the controlled-strain mode to determine model parameters. Then, the resulting constitutive equation was used to predict the stress-strain behavior of the same materials under controlled-stress mode. The constitutive equation proposed in this paper satisfactorily predicts the constitutive behavior of asphalt concrete all the way up to failure under various loading conditions including different stress-strain amplitudes, monotonic versus cyclic loadings, and different modes of loading.

Viscoelastic constitutive model for asphalt concrete under cyclic loading

FUNDAMENTAL PRINCIPLES. Pavement Types, Wheel Loads, and Design Factors. Stresses in Flexible Pavements. Stresses in Rigid Pavements. Vehicle and Traffic Considerations. Climate, Environment. The Economic Factor, Design Strategies, Systems Analysis. PROPERTIES OF PAVEMENT COMPONENTS: MATERIALS CHARACTERIZATION. Soil Classification. Materials Characterization. Soil and Base Stabilization. Subgrades. Bases and Subbases. Bituminous Surfaces. Material Variability. DESIGN OF FLEXIBLE PAVEMENTS. Design of Flexible Airport Pavements. Design of Flexible Highway Pavements. DESIGN OF RIGID PAVEMENTS. Design of Rigid Airport Pavements. Design of Rigid Highway Pavements. PAVEMENT EVALUATION AND REHABILITATION. Pavement Distress. Condition Surveys. Strengthening Existing Pavements.

Principles of Pavement Design

Principles of pavement design. second edition

AN EXAMINATION OF THE POTENTIAL AVAILABILITY OF AGGREGATE WITHIN THE CONTERMINOUS 48 STATES USING AN EXTANT PHYSIOGRAPHIC CLASSIFICATION SYSTEM IS PRESENTED. THE CLASSIFICATION SELECTED WAS A MODIFIED VERSION OF THE WOODS-LOVELL PHYSIOGRAPHIC-ENGINEERING SYSTEM, COMPRISED OF 97 PHYSIOGRAPHIC SECTIONS. THE ESTIMATED POTENTIAL ABAILABILITY OF AGGREGATE WAS RATED AT FOUR LEVELS, RANGING FROM ABUNDANT-TO- ADEQUATE TO SEVERE-PROBLEM. INDIVIDUAL PHYSIOGRAPHIC SECTION RATINGS WERE ASSIGNED FOLLOWING AN EXAMINATION OF THE MAJOR AGGREGATE TYPE(S) USED, THEIR DISTRIBUTION WITHIN THE SECTION, AND ANY QUALITY LIMITATIONS ASSOCIATED WITH THEIR USE. INFORMATION RELATIVE TO AGGREGATE TYPES AND CHARACTERISTICS WAS GATHERED FROM THE LITERATURE, PARTICULARLY BEDROCK AND SURFICIAL MAPS, AND FROM RESPONSES TO A MATERIALS QUESTIONNAIRE SENT TO EACH STATE HIGHWAY AGENCY. THE STUDY SHOWS THAT AGGREGATES ARE POTENTIALLY IN SHORT SUPPLY IN ABOUT ONE-THIRD OF THE CONTERMINOUS 48 STATES, I.E., THESE AREAS HAVE LIMITED-TO-SEVERE-PROBLEM RATINGS. SUCH AREAS ARE PRIMARILY COMPRISED OF REGIONAL TOPOGRAPHY FORMED FROM PREDOMINANTLY SANDSTONE AND SHALE BEDROCK OR FROM TRANSPORTED DEPOSITS DEFICIENT IN EITHER QUANTITY OR QUALITY OF SANDGRAVEL AND UNDERLAIN BY BEDROCK HAVING LITTLE OR NO AGGREGATE POTENTIAL. /AUTHOR/

A generalized investigation of the potential availability of aggregate by regional geomorphic units within the conterminous 48 states

Bases and Subbases

FOR EACH OF 97 PHYSIOGRAPHIC SECTIONS, AN ESTIMATE WAS MADE OF (A) THE FREQUENCY OF OCCURRENCE OF ORGANIC DEPOSITS AND (B) THE COMBINED FREQUENCY OF OCCURRENCE-SEVERITY RATING OF CLAYEY DEPOSITS. IN ORDER TO ASSESS THE REGIONAL CHARACTER OF THE POOR SUPPORT PROBLEM, A NATIONAL SOIL TEXTURAL MAP WAS DEVELOPED. FREQUENCY OF OCCURRENCE RATINGS FOR ORGANIC DEPOSITS WERE DETERMINED DIRECTLY FROM THIS MAP FOR EACH SECTION. FOR CLAYEY DEPOSITS, A SEVERITY SCALE, BASED ON A RELATIONSHIP BETWEEN THE SOIL TEXTURE AND THE UNIFIED SOIL CLASSIFICATION SYSTEM, WAS COMBINED WITH THE FREQUENCY OF OCCURRENCE RATINGS OF CLAYEY DEPOSITS OBTAINED FROM THE NATIONAL SOILS MAP. THE STUDY INDICATED THE LIMITED REGIONAL DISTRIBUTION OF ORGANIC TERRAIN IN THE 48 STATES. THIS DISTRIBUTION IS CONCENTRATED IN YOUTHFUL (GEOMORPHIC) GLACIAL AND COASTAL TERRAIN DUE TO THE RATHER POORLY INTEGRATED DRAINAGE SYSTEM OFTEN ASSOCIATED WITH THESE REGIONAL GEOMORPHIC AREAS. ALTHOUGH CLAYEY DEPOSITS OCCUR THROUGHOUT THE 48 STATES, MOST ARE FOUND EAST OF THE ROCKY MOUNTAINS BECAUSE THE CLIMATIC, TOPOGRAPHIC, AND PARENT MATERIAL FACTORS ARE GENERALLY MORE FAVORABLE THERE. /AUTHOR/

E. J. Yoder

Papers

Principles of Pavement Design

Principles of pavement design. second edition

A generalized investigation of the potential availability of aggregate by regional geomorphic units within the conterminous 48 states

Bases and Subbases

A generalized investigation of potentially poor soil support by regional geomorphic units within the conterminous 48 states