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This report presents information that is intended to aid the practicing engineer con-fronted with consideration of repeated loading on concrete structures. Investigations of the fatigue properties of component materials--concrete, reinforcing bars, welded reinforcing mats, and prestressing tendons--are reviewed. Application of this infor-mation to predicting the fatigue life of beams and pavements is discussed. [ABSTRACT FROM AUTHOR]

The present state of development of the mechanics for fiber reinforcing of port. land cement concrete by metallic, glass, plastic, and natural fibers is reviewed along with techniques for mixing and mix proportioning, placing, finishing, and actual and potential applications. [ABSTRACT FROM AUTHOR]

Epoxy compounds have found a wide variety of uses in the concrete industry as coatings, grouts, binders, sealants, bonding agents, patching materials, and general adhesives. Properties, uses, preparations, mixtures, application, and handling requirements of epoxy resin systems when applied to and used with concrete and mortar are presented. The adhesiveness of epoxy and its chemical, thermal, and physical properties are given. The modification of the foregoing properties to accommodate given situations is reviewed. Problems encountered in surface preparation are reviewed and procedures and techniques given to insure successful bonding of the epoxy to the other materials. Temperature conditioning of the base material and epoxy compound are outlined. The cleaning and maintaining of equipment is reviewed. Procedures to be followed in the application of epoxy compounds in the several use situations are given. The important factors which insure that the epoxy compound will harden (cure) and therefore perform its function are discussed together with alterations of the hardening rate. The allergenic and toxic nature of epoxies and the chemicals used with them in the industry create a hazard and precautions are detailed throughout the report. [ABSTRACT FROM AUTHOR]

This recommended practice covers the construction of concrete pavements and concrete bases without attempting to include inflexible specifications for procedures, materials, or equipment. References are made to specifications, but only as a guide to enable a selection of requirements suitable for a particular location or class of work. The document is slanted to some degree toward use by agencies other than state highway departments or turnpike authorities with presumably large and experienced engineering staffs, and with knowledge of past performance of pavements in the area. Siections are devoted to specifying, sampling, and testing materials, and to the possible influence of materials on skid resistance, economy, and durability. Maximum aggregate size is mentioned as sometimes relating to pavement durability. Subgrades and subbases are treated only as to final preparation for paving. Recommendations for forms are included as well as recommendations for projects using slipforms. Arrangement of joints is described, and references are given for guidance in using reinforcement. Sections on normal and high-early-strength concrete proportioning rely heavily on reference to the report of ACI Committee 211, but point out the special problems connected with pavement concretes and the use of admixtures in pavement concrete. Sections on mixing, placing, finishing, and curing concrete refer to other ACI reports where pertinent, but make recommendations for the special handling necessary in the case of pavements. Concrete bases are treated where procedures vary from those used for pavements, and recommendations and references are given for cold and hot weather concreting. [ABSTRACT FROM AUTHOR]

Reviews the experience of the Michigan Department of State Highways with the use of neoprene compression seals. Field experience and research that led to the development of specifications for their use are described. The specifications are discussed and a summary of regular condition surveys on sealed joints is presented. [ABSTRACT FROM AUTHOR]

This report presents an interim design method based on current practices for determining the pavement thickness and amount of reinforcing steel for continuously reinforced concrete pavement. Recommendations are also presented on end anchor-age systems. The pavement thickness design method is based on modifications of the design equations presented in the AASHO interim guide which was prepared after completion of the road tests in Illinois. This design procedure is construed to be a tentative one and is published at this time to provide the designer with guidelines, pending the development of more accurate procedures. [ABSTRACT FROM AUTHOR]

Consolidation is the process of removing entrapped air -from fresh concrete in the form. Several methods and techniques are available -- the choice depending mainly on the workability of the mix, placing conditions, and degree of deaeration desired. Some form of vibration is usually employed. This recommended practice includes up-to-date information on the mechanism of consolidation, and gives recommendations on equipment characteristics and pro-cedures for various classes of construction. [ABSTRACT FROM AUTHOR]

Large air and water pockets have been ob-served in the cores taken from well proportioned vibrated concrete pavements. Several parameters which may influence the volume of entrapped air in thin concrete sections compacted with spud vibra-tors are studied. Laboratory test results suggest that it is difficult to eliminate the entrapped air content in concrete slabs of stiff concrete com-pacted with spud type vibrators and for moderate vibration times ana vibrator amplitudes and fre-quencies. The results suggest that the use of a surcharge may be beneficial in reducing the en-trapped air content and a crushed stone concrete mix may yield lower entrapped air contents than a rounded stone concrete mix. [ABSTRACT FROM AUTHOR]

Curing is defined as the process of maintaining a satisfactory moisture content and a favorable temperature in concrete during hydration of the cementitious materials so that desired properties of the concrete are developed. Two systems of providing the required moisture are explained in detail: (I) main-taining a moist environment by application of water; and (2) prevention of loss of mixing water by use of sealing materials. Basic principles of successful curing are outlined, and commonly accepted methods, procedures, and materials are described. Recommendations are given for curing pavements and other slabs on ground; for structures and buildings; and for mass concrete. For each of these categories, methods, materials, time and tempera-ture of curing are recommended. Brief sections comment on curing requirements for precast products, shotcrete, preplaced aggregate concrete, refractory concrete, plaster, and other applications. [ABSTRACT FROM AUTHOR]

This state-of-the-art report outlines the historic background of the development of expansive cement concretes abroad and in this country, presents the relevant nomenclature, and summarizes the current status of expansive cements in the United States. The hydration chemistry of expansive cements is described, with emphasis on the components necessary for the formation of ettringite. The important factors in the choice of proportioning of materials are discussed, as well as the products of reaction, and heat of hydration. Various factors are discussed, which influence the rate and amount of expansion of all three types of expansive cement concretes. These include the chemical com-position, fineness and age of cement, water-cement ratio, mixing time, admixtures, aggregates, curing, temperature, restraint, and size and shape of specimens. The properties of expansive cement concretes are reported separately for shrinkage-compensating and self-stressing concretes. The properties considered in-clude workability, bleeding, time of setting, unit weight and yield, expansion, creep, shrinkage, compressive and bond strengths, modulus of elasticity, Poisson's ratio, coefficient of thermal expansion, and the resistance to various actions (deicer scal-ing, sulfate attack, cracking, and abrasion). Properties are also indicated on which no data are available at present. Field performance of shrinkage-compensating concrete is summarized. The in-fluences of restraint, aggregates, additives, ambient temperatures, forms, consistency, finishing, and curing are discussed. Examples of structural installations are presented, which include flat slabs, one-way pan joists, and two-way waffle slabs for parking garages, a folded plate roof for a bank, topping on a prestressed single tee parking deck structure, grade slabs and tilt-up panel walls for a department store, and an industrial floor. Five highway installations are described, including various spacings of contraction joints, continuously reinforced pavement as well as an unreinforced one, an application of self-stressing concrete, and the use of two bridge decks. The results of 17 tests on laboratory made structural elements of self-stressing concrete are summarized. These include tests on pipes, slabs, beams, frames, columns, and hyperbolic paraboloid. A brief review is given of some overseas experience. Needed areas of research and development are discussed with respect to expansive cements, material properties and behavior, and applications. An extensive bibliography is presented. [ABSTRACT FROM AUTHOR]

Most joints, and some cracks in concrete structures, require sealing against the adverse effects of environmental and service conditions. This report is a guide to better understanding of the properties of joint sealants and to where and how they are used in present practice. Described and illustrated are: the functioning of joint sealants; required properties, available materials and applicable specifications for field-molded sealants and pre-formed sealants such as waterstops, gaskets or compression seals; determination of joint movements, widths, and depths; outline details of joints and sealants used in general structures, fluid containers and pavements; methods and equipment for sealant installation including preparatory work; performance of sealants; and methods of repairing defective work or maintenance resealing. Finally, improvements needed to insure better joint sealing in the future are indicated. [ABSTRACT FROM AUTHOR]

Deformations at the corners of prestressed and reinforced concrete slabs were measured to study warping and its effect on the strength of pavement for Kuwait International Airport. The principal variables for the prestressed pavement were the length of slab, concrete strength, and compressive stresses through prestressing forces. For the reinforced concrete pavements the principal variables were the location of the corners at which the measurements were taken. The observations of the vertical movement due to warping at different times and different days were recorded and plotted in curves, for comparison between the vertical movement at the corners of the different slabs. A limited study for the extension of the warping along the two perpendicular edges meeting at the corner was done in one case. Also, a loading test at the corner of only one slab was done for investigating the value of the load required to bring the corner down to contact point and to find out if any failure could take place at the corner under the design load. [ABSTRACT FROM AUTHOR]

This guide provides a system for reporting on the condition of concrete in service. It includes a check list of the many details to be considered in making a report, and provides standard definitions of 40 terms associated with the durability of concrete. Its purpose is to establish a uniform system for evaluating the condition of concrete. [ABSTRACT FROM AUTHOR]

Methods are suggested for material selection, moisture control, and compaction or treatment of soils and materials to assure volume stability and uniform support for concrete pavements. Various environments are considered and appropriate methods of subgrade preparation outlined. Base and subbase functions are defined and adaptability of types of subbases discussed. Placement of materials to aid in subbase moisture control was emphasized in shoulder design. References to pertinent technical manuals and articles are made throughout and AASHO and ASTM standard methods and tests are keyed where appropriate. A soction on recognition of causes of deficiencies in existing pavements is included to alert the engineer to the consequences of improper construction or adverse environment. [ABSTRACT FROM AUTHOR]

This report considers factors pertinent to the prestressing concept, reviews results of a number of experimental projects, and presents design details for experimental sections of prestressed pavement which can be built following existing highway construction practices in North America, and using commercially available prestressing equipment. Data are presented for slabs from 400 to 900 ft ( 120 to 270 m) long, 24 ft (7.3 m} wide, and 5 in. ( 13 em) thick, with post-tensioned tendons spaced 24 in. (61 em) on centers to provide at least 100 psi (7 kgf/cm²} effective prestress at midlength of the slab. Details are suggested for 600-ft (180-m) slabs. Post-tensioning is recommended to simplify operations using developed techniques, and to avoid the cost of pavement anchor blocks. The suggested design is supported by data from recent research on the performance of thin slabs under highway traffic. Length changes anticipated are predicted on the basis of trends in earlier experiments. The design for slab ends is intended to conservatively reinforce these critical locations, assure even joints, protect the foundation, and aid drainage rather than to meet minimum design needs with the most economical construction. [ABSTRACT FROM AUTHOR]

An experimental investigation was carried out to determine the resistance of popout formation in mortar. It was found that the required pressure to produce popouts on a concrete surface, from a spherically shaped particle near the surface, is directly proportional to the distance of the particle from the surface, and the tensile strength of the concrete, and inversely proportional to the size of the particle. [ABSTRACT FROM AUTHOR]

A direct method of solving for deflected shapes of freely discontinuous pavement slabs subjected to a variety of loads including transverse loads in plane forces and externally applied couples is presented. The method applies to slabs with freely variable foundation support including holes in the subgrade and rapidly solves finite element slab equations developed, unhindered by closure parameters necessary in iterative techniques of solution. A computer program uses equations and techniques developed. Sample problems illustrate generality of the method and convenience to the user. Results compare well with closed-form solutions and with previous solutions developed by other techniques. [ABSTRACT FROM AUTHOR]

This report updates the 1958 report and presents further information on bonded concrete resurfacing. Consideration is also given to concrete overlays on flexible pavements. Design procedures which will give dependable results in situations evaluated by mature engineering judgment are presented; however, note is made that they are subject to further refinement. [ABSTRACT FROM AUTHOR]

Describes the construction of a prestressed concrete runway and taxiway for an airport in Portugal. The pavement was pretensioned longitudinally and posttensioned transversely. The runway is about 4000 m (13,100 ft) long and 60 m (197 ft) wide while the taxiway is approximately 3200 m (10,500 ft) long and 30 m (98 ft) wide. Each month about 270 tons (300 U.S. tons) of prestressing steel was installed and nearly 5500 cu m (7200 cu yd) of concrete was placed. The project was completed in 38 weeks. [ABSTRACT FROM AUTHOR]

Consolidation is the process of removing entrapped air from fresh concrete in the form. Several methods and techniques are available -- the choice depending mainly on the workability of the mix, placing conditions, and degree of deaeration desired. Some form of vibration is usually employed. This recommended practice includes up-to-date information on the mechanism of consolidation, and gives recommendations on equipment characteristics and procedures for various classes of construction. [ABSTRACT FROM AUTHOR]

Curing is defined as the process of maintaining a satisfactory moisture content and a favorable temperature in concrete during hydration of the cementitious materials so that desired properties of the concrete are developed. Two systems of providing the required moisture are explained in detail: (I) main-taining a moist environment by application of water; and (2) prevention of loss of mixing water by use of sealing materials. Basic principles of successful curing are outlined, and commonly accepted methods, procedures, and materials are described. Recommendations are given for curing pavements and other slabs on ground; for structures and buildings; and for mass concrete. For each of these categories, methods, materials, time and tempera-ture of curing are recommended. Brief sections comment on curing requirements for precast products, shotcrete, preplaced aggregate concrete, refractory concrete, plaster and other applications. [ABSTRACT FROM AUTHOR]