Rapid Inventory of Earthquake Damage (RIED)

The 25 January 1999 Quindío earthquake in Colombia was a major disaster for the coffee-growing region in Colombia. Most of the damage occurred in the city of Armenia and surrounding villages. Damage due to earthquakes is strongly related to topographic and subsurface geotechnical conditions underneath structures and houses. The RIED project used aerial photographs to obtain a rapid inventory of the earthquake damage right after the seismic event. This inventory was subsequently used to identify any existing relation with subsurface- and topographic conditions. Hazard zonation maps were made on the basis of seismic response analysis of a three-dimensional model of the subsurface that has been created in the GIS. Also indicative zonation maps were created outlining potential areas where topographic amplification may occur. These seismic zonation maps delineate those areas that are most likely affected by subsurface and topographic resonance effects during a future and similar earthquake. The maps have been presented to the city planning authorities of Armenia so that reconstruction of the damaged areas can be carried out in such a way that high risk areas will be avoided or that structures and houses will be built according to the standards for high seismic risk areas

Non-Newtonian Behaviors of Crumb Rubber-Modified Bituminous Binders

Crumb rubber-modified bitumen (CRMB) has been utilized in the asphalt paving industry for decades due to its various benefits. The complex interaction between bitumen and crumb rubber as well as the addition of warm-mix additives makes the typical laws of Newtonian fluids insufficient to describe the behaviors of highly modified bituminous binders. To systematically explore the non-Newtonian behaviors of CRMB, a dynamic shear rheometer was utilized to apply shear loading on the samples at various temperatures and shear rates. Results show that the viscosity of different binders are highly temperature- and shear rate-dependent, while highly modified binders exhibit more obvious shear-thinning behaviors at certain temperatures. With the help of zero shear viscosity and yield stress, the shear-thinning behaviors of non-Newtonian binders can be sufficiently characterized. The Arrhenius equation is invalid to describe viscosity-temperature characteristics of bitumen in the non-Newtonian region. A second-order polynomial function was proposed to characterize the viscosity-temperature dependence with a high correlation degree

Framework for replacing steel with aluminum fibers in bituminous mixes

This research explores the incentives for replacing steel fibers with aluminum fibers in fiber modified bituminous mixes. In this work the focus is on fiber modified bituminous mixes especially designed for induction heating. Inductive fibers are heated up because eddy currents are generated - according to Joule’s law - when alternating magnetic field is applied by electro-magnetic induction coil. Aluminum fiber-type particles are proposed as an alternative solution for developing corrosion resistant and lightweight bituminous mixes capable to be induced by electro-magnetic fields. In another publication (Pavlatos et al., Inductive bituminous mortar with steel and aluminum fibers, Advances in Materials and Pavement Performance Prediction, Submitted, 2018), a finite element three-dimensional model is developed in order to determine the effective electrical conductivity of steel and aluminum fiber modified bituminous mortar, as well as to show the potential utilization of alternative particles for developing multi-functional paving materials with improved properties

Inductive bituminous mortar with steel and aluminum fibers

This research presents the implementation of a finite element model analysis for assessing the potential of utilizing alternative fibers for the development of inductive bituminous mixes with lower total weight, higher resistance against corrosion, and sufficient induction heating efficiency. Aluminum fibers areselected as the metallic modifier in bituminous mixes against the commonly applied steel fibers in order to develop inductive materials. The main reasons for applying aluminum fibers in bituminous mixes are presented in (Pavlatos et al., Framework for replacing steel with aluminum fibers in bituminous mixes, Advances in Materials and Pavement Performance Prediction, Submitted, 2018). A real fiber modified bituminous specimen is reconstructed by means of CT scans and its effective electrical conductivity is calculated assuming steel and aluminum fibers. Since steel fiber modified bituminous mixes have already been used successfully for induction heating, the aim of this work is to demonstrate that aluminum fiber modified bituminous mixes exhibit equally good properties as the steel fiber modified bituminous mixes for induction heating

Study of Hydroplaning Risk on Rolling and Sliding Passenger Car

Hydroplaning speed is known to vary over a range of tire slipping conditions from free rolling to completely skidding. An attempt has been made to simulate two extreme conditions of hydroplaning i.e. when the tire is completely rolling (0% slip) and a completely locked tire (100% slip). ASTM standard smooth tire moving over the plane pavement surface is considered in the model. The analyses showed that the hydroplaning risk associated with the locked tire is more than the rolling tire. The modeling was carried out using the commercial finite element software package, ABAQUS.Delft University of Technolog