These pavements do not use any reinforcing steel. JPCP‟s are constructed with contraction joints which direct the natural cracking of the pavement. Three main types of concrete pavements commonly used are Jointed plain concrete pavement (JPCP), jointed reinforced concrete pavement (JRCP), and continuously reinforced concrete pavements (CRCP). Joint spacing is determined by the slab panel dimensions.
In addition to the slab panels, temperature reinforcements must be designed to control cracking behavior in the slab. The concrete slab is constructed according to a designed choice of plan dimensions for the slab panels, directly influencing the intensity of thermal stresses occurring within the pavement. Rigid pavements are generally constructed in three layers - a prepared subgrade, base or subbase, and a concrete slab. Due to the relatively low tensile strength of concrete, thermal stresses are extremely important to the design considerations of rigid pavements. As pavement design has progressed, many highway engineers have noted that thermally induced stresses in rigid pavements can be just as intense as those imposed by wheel loadings. In addition to design criteria such as traffic loadings, tensile stresses due to thermal energy must also be taken into consideration. Fatigue failure is common among major roads because a typical highway will experience millions of wheel passes throughout its service life. One major design consideration of rigid pavements is reducing fatigue failure due to the repeated stresses of traffic. The typical designed service life of a rigid pavement is between 30 and 40 years, lasting about twice as long as a flexible pavement. Rigid pavements must be designed to endure frequently repeated traffic loadings. The reason for its popularity is due to its availability and the economy. Portland cement concrete (PCC) is the most common material used in the construction of rigid pavement slabs. Offering high quality riding surfaces for safe vehicular travel, they function as structural layers to distribute vehicular wheel loads in such a manner that the induced stresses transmitted to the subgrade soil are of acceptable magnitudes. Like flexible pavements, rigid highway pavements are designed as all-weather, long-lasting structures to serve modern day high-speed traffic. In addition, they commonly serve as heavy-duty industrial floor slabs, port and harbor yard pavements, and heavy-vehicle park or terminal pavements.
1) Introduction ( Pavement definition, Types, Wheel loads, Tire pressure, Types of pavement Distress, Serviceability, Design Process and Strategies).Ģ) Stresses in Flexible Pavements (Layered system concept, Material behavior &type of theory, Stresses & displacement in one layer or system, stresses &displacement in Burmister two layer system stresses & displacement in Burmister three layer system).ģ) Stresses in Rigid Pavements ( Bending thin plate (plate bending theories, the differential equation of the deflection surfaced, bouncing conditions simply supported rectangular plates under sinusoidal load, navier solution for simply supported rectangular plates, finite difference solution for simply supported rectangular plates).Ĥ) Plates on the Elastic Foundations (foundation models, rectangular plates on Winkler foundation finite difference solution for plate in Winkler foundation)ĥ) Stresses in Rigid Pavements (causes of stresses, stresses due to wheel loads Westergaard solution, Pickett & Ray charts (influence charts) Reddy & Paranesh charts, stresses due to friction ( stresses due to uniform temperature to drop or due to uniform temperature increase, temperature reinforcement, stresses due to warping, types of joints, stresses in dual bars, shear transfer, double group action).Ħ) Equivalent Single Wheel Load & AASHTO Load Equivalency Factors Equivalent single wheel load principle (ESWL), ESWL criteria & concept, ESWL analysis, flexible pavement ESWL, rigid pavement ESWL, AASHTO equivalency factors, Traffic growth.ħ) Design of Flexible Highway Pavement (General, Failure conditions of flexible highway pavement, Distress modes, Major methods for design of flexible highway pavement, AASHTO Guide 1993 method ,Applications).Ĩ) Design of Highway Rigid Pavement (Pavements types, plain concrete pavement simply reinforcement concrete pavement, continuously reinforced concrete pavement, priestesses concrete pavements methods, design of highway rigid pavement, the Portland cement association method, AASHTO Guide 1993 method).Rigid pavements are generally used in constructing airports and major highways, such as those in the interstate highway system.
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