Many agencies use the AASHTO Guide for Design of Pavement Structures to design their pavement systems. The limitation inherent in this method is the empirical nature of the decision process, which was derived from a road test conducted almost 45 years ago in Ottawa, Illinois. The newly released Mechanistic-Empirical Pavement Design Guide (MEPDG), based on NCHRP Study 1-37A, has adopted a mechan...

The fundamentally changing nature of fracture in brittle coatings on compliant substrates with diminishing coating thickness is examined. Attention is focused on cracking induced by concentrated loading with a spherical indenter at the top surface. It is shown that the fracture mode undergoes transitions, from top-surface ring cracking around the contact (“thick-coating” region) to bottom-surfa...

Environmental stress cracking (ESC) is a phenomenon in which a plastic resin is degraded by a chemical agent while under stress, and it is the leading cause of plastic component failure. It is a solvent-induced failure mode, in which the synergistic effects of the chemical agent and mechanical stresses result in cracking. A recent study showed that 25% of plastic part failures are related to ES...

Concrete is generally viewed as a durable and long-lasting construction material. However, the long-term performance of a concrete structure can be greatly compromised by early-age cracking. One recent informal estimate from the industry places this as a $500 million problem in the U.S. alone, with some ready-mix companies experiencing early-age issues on as many as 70 % of their jobs. As is of...

Undesired wall thickness distribution and flanging cracking easily occur in reverse drawing–flanging combined processes of steel spokes when improper process parameters are used. Thus, based on GRA (grey relational analysis) and FEM (finite element method), a GRA model for a reverse drawing–flanging combined process for high strength steel B550CL spoke was established and validated. The results...

This review covers recent advances and work on the microstructure features, mechanical properties and cracking processes of conducting polymer film/coating- substrate structures under different testing conditions. An attempt is made to characterize and quantify the relationships between mechanical properties and microstructure features. In addition, the film cracking mechanism on the micro scal...

This paper describes a web-based finite element program called portal of damage. The purpose of the program is the numerical simulation of reinforced concrete framed structures, typically buildings, under earthquakes or others exceptional overloads. The program has so far only one finite element based on lumped damage mechanics. This is a theory that combines fracture mechanics, damage mechanic...

[1] The development of transient thermal stress in suboceanic mantle is investigated on the basis of two-dimensional thermoviscoelastic models incorporating composite rheology appropriate for dry oceanic lithosphere. Thermal stress is shown to be sufficiently high to deeply fracture the coldest part of lithosphere, e.g., to the depth of at least 30 km (and possibly down to 50 km) in 100-Ma-old ...

An assessment of newly reconstructed reinforced concrete barrier walls on a highway bridge near Montreal indicated intense transverse cracking only a few days after concreting. Subsequent inspection of other concrete bridges in urban areas confirmed that such cracking is not uncommon. Analytical models, together with field and estimated data, were used to study the magnitude and roles of the fa...

[1] In mountainous landscapes the role of periglacial processes in producing sediment is poorly defined, despite evidence of abundant talus slopes. Ice growth in rock has long been recognized as an efficient erosion mechanism, but the effects have not been readily applied to landscape evolution in response to tectonic and climatic forcing. Here, we quantify how and where ice-driven mechanical e...