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Inspection methods of reinforcement parameters of concrete structures
A.V. Ulybin
Magazine of Civil Engineering , 2012,
Abstract: One of the main objectives during the detailed examination of the supporting structures made from any construction materials is receiving data to perform calculations. For reinforced concrete structures the most difficult task is to determine the parameters of steel reinforcement, as it is always under a protective layer of concrete.The paper deals with the main problem of reinforcement parameters determination of concrete structures in the inspection. The basic well-known tracks of a solution to this problem are analyzed. The most reliable and accurate methods of reinforcement parameters determination are revealed.The magnitude of error of the magnetic inspection method in the determination of the diameter of reinforcement and the coverage is experimentally detected. The availability data of applying the method of hardness measuring for the reinforcement class determination is adduced.
The Dynamics of the Skin Temperature of the Dead Sea  [PDF]
Roni Nehorai,Nadav Lensky,Steve Brenner,Itamar Lensky
Advances in Meteorology , 2013, DOI: 10.1155/2013/296714
Abstract: We explored the dynamics of the temperature of the skin layer of the Dead Sea surface by means of in situ meteorological and hydrographic measurements from a buoy located near the center of the lake. The skin temperature is most highly correlated to air temperature (0.93–0.98) in all seasons. The skin temperature is much less correlated to the bulk surface water temperature in the summer (0.80), when the lake is thermally stratified, and uncorrelated in the winter, when the Dead Sea is vertically mixed. Low correlations were found between the skin temperature and the solar radiation and wind speed in all seasons. The skin, with its low thermal inertia, responds immediately to the atmospheric forcing. Heat fluxes across the sea surface are also presented. The high correlation of skin temperature to air temperature with minimal time lag is a result of the nearly immediate response of the thin skin layer to the surface heat fluxes, primarily the sensible heat flux. 1. Introduction Sea surface temperature (SST) is a critically important parameter in the study of ocean-atmosphere interactions. SST has a major role in atmospheric models, weather forecasting, climate change models, and energy balance calculations. SST can be measured from satellites and represents a very thin boundary layer (~10?μm skin layer) between the turbulent ocean and atmospheric layers. At this boundary layer, exchanges of sensible and latent heat occur, and long-wave radiation is emitted and absorbed [1]. Different processes act on the skin layer and on the water body beneath it (bulk layer), resulting in a difference between the skin and bulk temperatures. Saunders [2] presented a simple theory in which the difference between bulk temperature and skin temperature, commonly termed “the skin effect” ( ), is proportional to the heat flux (including sensible, latent, and long wave radiative heat fluxes from ocean to atmosphere) and inversely proportional to the kinematic stress (wind friction); the theory is limited to conditions of negligibly low solar radiation and excludes very low wind intensity. One of the predictions of this model is that the ocean is usually covered with a “cool skin”. The skin effect is estimated using measured in situ bulk temperature and long wave radiation from which the skin temperature is calculated [3]. The effects of wind, waves, and the upper layer mixing on the boundary layer have been investigated [3–5]. These studies have shown that wind mixes the upper layer, cooling the skin layer, and that breaking waves momentarily destroy the skin layer, which
Raising the Dead without a Red Sea-Dead Sea project? Hydro-economics and governance
D. E. Rosenberg
Hydrology and Earth System Sciences (HESS) & Discussions (HESSD) , 2011,
Abstract: Seven decades of extractions have dramatically reduced Jordan River flows, lowered the Dead Sea level, opened sink holes, and caused other environmental problems. The fix Jordan, Israel, and the Palestinians propose would build an expensive multipurpose conveyance project from the Red Sea to the Dead Sea that would also generate hydropower and desalinate water. This paper compares the Red-Dead project to alternatives that may also raise the Dead Sea level. Hydro-economic model results for the Jordan-Israel-Palestinian inter-tied water systems show two restoration alternatives are more economically viable than the proposed Red-Dead project. Many decentralized new supply, wastewater reuse, conveyance, conservation, and leak reduction projects and programs in each country can together increase economic benefits and reliably deliver up to 900 MCM yr 1 to the Dead Sea. Similarly, a smaller Red-Dead project that only generates hydropower can deliver large flows to the Dead Sea when the sale price of generated electricity is sufficiently high. However, for all restoration options, net benefits fall and water scarcity rises as flows to the Dead Sea increase. This finding suggests (i) each country has no individual incentive to return water to the Dead Sea, and (ii) outside institutions that seek to raise the Dead must also offer countries direct incentives to deliver water to the Sea besides building the countries new infrastructure.
Raising the dead without a Red Sea-Dead Sea canal? Hydro-economics and governance
D. E. Rosenberg
Hydrology and Earth System Sciences Discussions , 2010, DOI: 10.5194/hessd-7-9661-2010
Abstract: Seven decades of extractions have dramatically reduced Jordan River flows, lowered the Dead Sea level, opened sink holes, and caused other environmental problems. The fix Jordan, Israel, and the Palestinians propose would build an expensive multipurpose canal from the Red Sea to the Dead Sea that would also generate hydropower and desalinated water. This paper compares the Red-Dead project to alternatives that may also raise the Dead Sea level. Hydro-economic model results for the Jordan-Israel-Palestinian inter-tied water systems show two restoration alternatives are more economically viable than the proposed Red-Dead project. Many decentralized new supply, wastewater reuse, conveyance, conservation, and leak reduction projects and programs in each country can together increase economic benefits and reliably deliver up to 900 MCM/year to the Dead Sea. Similarly, a smaller Red-Dead project that only generates hydropower can deliver large flows to the Dead Sea when the sale price of generated electricity is sufficiently high. However, for all restoration options, net benefits fall and water scarcity rises as flows to the Dead Sea increase. This finding suggests (i) each country has no individual incentive to return water to the Dead Sea, and (ii) outside institutions that seek to raise the Dead must also offer countries direct incentives to deliver water to the Sea besides building the countries new infrastructure.
Corrosion Evaluation of Modified Reinforcement Concrete by Electrochemical Noise Techniques
Nú?ez-Jaquez,R.E.; Gaona-Tiburcio,C.; Uruchurtu-Chavarin,J.; Barrios-Durstewitz,C.P.; Almeraya-Calderón,F.; Martínez-Villafa?e,A.;
Portugaliae Electrochimica Acta , 2005,
Abstract: the reinforced concrete is a versatile and resistant material and it is used in several construction projects; for this reason the improvement of concrete properties and protection of the reinforced steel against corrosion is an active research area. diverse methods are applied on the steel or on the concrete to protect them. the present investigation is directed towards the development and performance evaluation against corrosion of the reinforcement concrete, containing two different fly ash and blast furnace slag mixtures, in saline environments, and the corrosive evaluation was performed by electrochemical noise technique. the results show an improvement of the steel reinforcement corrosion resistance.
Studies and research work on the reinforcement steel and concrete surface corrosion protection methods
Gheorghe Croitoru
Urbanism. Arhitectura. Constructii , 2013,
Abstract: Methods for reinforcement steel corrosion protection and concrete surface protection are analyzed. Knowing the corrosion process mechanism reinforcement steel can be protected by different protection methods even in the presence of crevices larger than those anticipated by design. The selection of the corrosion protection method depends on the reduction level of the reinforcement steel corrosion which in its turn is determined by the atmospheric conditions. The selection of the accelerated corrosion test conditions was made revealing the mechanism of the processes that take place at the steel reinforcement surface under natural weathering conditions. Crevices ranging from 0.05mm to 1.00mm or larger were opened by bending reinforced concrete girders on special equipment and were maintained all over the period of the corrosion resistance study.
Electrochemical Impedance Spectroscopy Of Epoxy-Coated Steel Exposed To Dead Sea Water  [PDF]
Sami Masadeh
Journal of Minerals and Materials Characterization and Engineering (JMMCE) , 2005, DOI: 10.4236/jmmce.2005.42007
Abstract: Electrochemical impedance tests were applied to steel specimens which were coated by epoxy and tested after immersion in Dead Sea water for different periods at room temperature and at 50C. Results taken from Nyquist and Bode plots and as were analyzed by means of software provided with the instrument. Results were presented as the values of capacitance and resistance (Cdl and Rct). Results show that degradation occurred after immersion in the test solution, and were more severe at higher temperature. Specimens were examined under scanning electron microscope, and micrographs showed clear rupture and degradation in epoxy coatings.
Modelling chemistry over the Dead Sea: bromine and ozone chemistry
L. Smoydzin,R. von Glasow
Atmospheric Chemistry and Physics (ACP) & Discussions (ACPD) , 2009,
Abstract: Measurements of O3 and BrO concentrations over the Dead Sea indicate that Ozone Depletion Events (ODEs), widely known to happen in polar regions, are also occuring over the Dead Sea due to the very high bromine content of the Dead Sea water. However, we show that BrO and O3 levels as they are detected cannot solely be explained by high Br levels in the Dead Sea water and the release of gas phase halogen species out of sea borne aerosol particles and their conversion to reactive halogen species. It is likely that other sources for reactive halogen compounds are needed to explain the observed concentrations for BrO and O3. To explain the chemical mechanism taking place over the Dead Sea leading to BrO levels of several pmol/mol we used the one-dimensional model MISTRA which calculates microphysics, meteorology, gas and aerosol phase chemistry. We performed pseudo Lagrangian studies by letting the model column first move over the desert which surrounds the Dead Sea region and then let it move over the Dead Sea itself. To include an additional source for gas phase halogen compounds, gas exchange between the Dead Sea water and the atmosphere is treated explicitly. Model calculations indicate that this process has to be included to explain the measurements.
Modelling chemistry over the Dead Sea: bromine and ozone chemistry  [PDF]
L. Smoydzin,R. von Glasow
Atmospheric Chemistry and Physics Discussions , 2009,
Abstract: Measurements of O3 and BrO concentrations over the Dead Sea indicate that Ozone Depletion Events (ODEs), widely known to happen in polar regions, are also likely to occur over the Dead Sea due to the very high bromine content of the Dead Sea water. However, we show that BrO and O3 levels as they are detected cannot solely be explained by high Br levels in the Dead Sea water and the release of gas phase halogen species out of sea borne aerosol particles and their conversion to reactive halogen species. It is likely that other sources for reactive halogen compounds are needed to explain the observed concentrations for BrO and O3. To explain the chemical mechanism taking place over the Dead Sea leading to BrO levels of several pmol/mol we used the single column model MISTRA which calculates microphysics, meteorology, gas and aerosol phase chemistry. We performed pseudo Lagrangian studies by letting the model column first move over the desert which surrounds the Dead Sea region and then let it move over the Dead Sea itself. To include an additional source for gas phase halogen compounds, gas exchange between the Dead Sea water and the atmosphere is treated explicitly. Model calculations indicate that this process has to be included to explain the measurements.
Study of Sharp-cut Decrease of Dead Sea
O. Dhaimat,S. Dhaisat
Journal of Applied Sciences , 2006,
Abstract: This study was planned to examine the clear-cut changes that have taken place in the Jordan Valley, specially the Dead Sea during the latest six decades. To do that various modern and technical means basically remote-sensing and GIS geographic information system applications were employed. Despite the imprecision, Satellite images were more efficient compared with other filed work photographs and maps in saving both money and time. Having known that most pools, lakes and dams are surrounded by forests, the delineation processes for these bodies by using remote-sensing and GIS techniques become easier and achieve better results. The reason that stands behind such an assumption is the chemical and physical composition of the water that makes the electromagnetic waves reacts in a different manner from other surfaces. In addition to their topographic forms, water body surfaces are in a sharp contrast with other surfaces, Vis, the earth. So due to the vital economical as well as environmental importance of the Dead Sea for Jordan and the region in general, this study was designed to explore the constant dangerous changes that take place in this area. Undoubtedly, the main dangerous systems from the notable decrease of water amount in this unique sea, were high evaporation due to its location at the lowest spot of land and dams and other irrigation projects at its tributaries.
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