The aim of the present research is to evaluate the degree of deterioration by means of stress waves. In this study, the stress waves generated by the impact of a steel ball on concrete surface are recorded by a displacement receiver 200 mm away. The received signal is analyzed in the frequency domain. The frequencies of the dominant response in the spectrum are used to evaluate the depth of det...

Late Miocene "Lake Pannon" (~11.3 Ma) was a remnant of the Central Paratethyan Sea. Successive freshening and constantly changing environmental conditions, like oxygenation, nutrition and substrate led to a well-documented radiation in molluscs and ostracods. Among ostracods (small crustaceans), Cyprideis is one of the most common genera in "Lake Pannon", as well as in several other ancient lak...

The aim of this study is to gain a better understanding of the conceptual model of contaminant transport and fate in cases of NAPL pollution in mega-site contexts in order to improve the design of remedial strategies. The area where the study was carried out is an unconfined aquifer of alluvial fans in the Tarragona Petrochemical Complex (Spain). Two boreholes were drilled and continuous cores ...

A total of 24 tephra-bearing volcanic layers have been recognized between 550 and 987 m depth in the Siple Dome A (SDM-A) ice core, in addition to a number already recognized tephra in the upper 550 m (Dunbar et al., 2003; Kurbatov et al., 2006). The uniform composition and distinctive morphological of the particles composing these tephra layers suggest deposition as a result of explosive volca...

Testing methods are required for estimating prestress losses in Prestressed Concrete (PC) girder-bridges. They mainly include destructive approaches which cause significant damages. Conversely, dynamic nondestructive unsuitable. Given these findings, a novel method identifying residual force simply supported PC girder-bridges was implemented. Following the vertical load application three-point ...

Microbes, some of which may be viable, have been found in ice cores drilled at Vostok Station at depths down to approximately 3,600 m, close to the surface of the huge subglacial Lake Vostok. Two types of ice have been found. The upper 3,500 m comprises glacial ice containing traces of nutrients of aeolian origin including sulfuric acid, nitric acid, methanosulfonic acid (MSA), formic acid, sea...

Central East Antarctic ice cores preserve stratigraphic records of mineral dust originating from remote sources in the Southern Hemisphere, and represent useful indicators of climatic variations on glacial-interglacial time scales. The peripheries of the East Antarctic Ice Sheet, where ice-free areas with the potential to emit dust exist, have been less explored from this point of view. Here, w...

The Serpent Mound structure is a deeply eroded ancient impact in south central Ohio, about 8.0 km across. The age of the structure is poorly constrained by the geology. It post-dates the Lower Mississippian (ca.330 Ma) Cuyahoga Formation and predates Illinoisian glacial deposits. We analyzed the directions of magnetization of 60 rock samples taken from borehole cores drilled within and in the v...

There are different test methods to determine the abrasion resistance of concrete subjected to number of various types of abrasion. There are number of different tests used in various countries and it is clear that there is no single test that adequately measures the abrasion resistance of concrete under all conditions. This paper covers the summary and classification of the various abrasion te...