bluuebunny/crossref_metadata_2025_split huggingface dataset:
Die Bohrwiderstandsmeßmethode / A Method to determine the resistance with respect to drilling
Authors: Kugele C. 
Published: November 2014

Abstract
The German Centre for Craftsmanship and Preservation of Historic Monuments performs intensive help oriented towards practical applications of a testing apparatus for non-destructive assessment of the condition of historical wooden structures. Possibilities and limits of a resistance drilling measuring apparatus are clearly demonstrated using as an example the Peace Church of the Holy Trinity at Swidnica, Poland, which is a monumental timber-framed building serving for a congregation of 7500. By means of the above mentioned apparatus, the task of assessing the condition of the completely faced and painted interior supporting structure was successfully solved. Damage inside the timber as well as structural changes, types of joints, species of timber, and the load transferring capability of the joints were determined. The restoration of the church dealing with these aspects is nearly completed. One can state that there were no "bad surprises " and the estimated expenditures could be maintained. This is an excellent result, especially in such a sensitive and cost-intensive area like the restoration ofhistoric monuments.
Selection of Consolidants for Use on the Tower of Belem / Auswahl eines Steinfestigers für den Turm von Belem
Authors: Rodrigues J. Delgado , Pinto A.P. Ferreiro , Charola A.E. , Aires-Barros L. , Henriques F.M.A. 
Published: November 2014

Abstract
During the exterior conservation project of the Tower of Belem, Lisbon, it was noticed that although most of the Lioz limestone used in its construction was in good condition, some specific areas presented severe powdering and flaking deterioration patterns. These are mainly due to the effect of natural weathering, including anthropogenic air-pollution, on poorer quality Lioz limestone. Since the deterioration affects mainly the immediate surface and subsurface of the stone blocks, the application of stone consolidants was considered as the most appropriate solution for this problem. This paper describes the difficulties encountered in the evaluation of the tested consolidants-an ethyl silicate ester, an acrylic resin and an epoxy resin-applied in situ. The laboratory and on-site testing used in the final selection are described as well as the actual approach to consolidating the different areas that required this treatment.
Einfluss von Rissen in hydrophobiertem Beton auf den kapillaren Wassertransport / Influence of cracks in water repellent concrete on capillary water movement
Authors: Limit P. , Wittmann F.H. 
Published: November 2014

Abstract
In practice, hydrophobing impregnation has been established as an effective surface protection system against water and de-icing salt attack. Cracks in concrete, whether impregnated by a hydrophobing treatment or not, are unavoidable and can therefore lead to damage. In absorption tests on laboratory samples, the significant influences of cracks on the penetration behaviour of capillary water have been determined and quantified. The experimental results show that the water uptake depends on the craclc width and the penetration depth of the hydrophobing agent. There exists a 'critical' crack width depending on the penetration depth of the hydrophobing agent which can maintain the hydrophobing behaviour. Finally practical conclusions of the present work are drawn.
Abdichtmaterialien gegen drückendes Wasser und Diesel mit verbesserter Umweltverträglichkeit / Sealing Materials against Pressuring Water and Diesel with Optimized Ecotoxicology
Authors: Mang Th. , Haulena F. 
Published: November 2014

Abstract
Sealing materials against pressuring water and leaking diesel have been developed as shaped gaskets, pastes and liquid injection materials based on acrylic polymers. Not only do these have optimized application properties, they are also greatly improved in ecotoxicology and working safety.
Eindringtiefe eines Hydrophobierungsmittels als Funktion der Qualität, des Feuchtigkeitsgehaltes und des Alters des Betons / Penetration depth of a water repellent agent as a function of quality, humidity and age of concrete
Authors: Moetsch H.A. , Meier St. , Gerdes A. , Wittmann F.H. 
Published: November 2014

Abstract
Service life and lifetime of a concrete structure are not only depending on mechanical but also on chemical loads. Therefore precautions are often taken into account already in the planning- or construction phase. Certain protective measures such as water repellent treatment need preliminary tests on the finished concrete surface, in order to be applied in an optimal way . The present paper describes the preliminary tests performed on three tunnels of the second section of the Swiss National Highway N5 (Grenchen - Zuchwil) in the area of Solothurn. For the construction of the three tunnels different qualities of concrete and different types of form work were used. Furthermore the selected sections of the tunnels differ also from age and environmental conditions. A new two-chamber measuring cell developped at the Institute for Building Materials of ΕΤΗ-Zurich was applied to determine the capillary suction capacity of selected tunnel sections. Values measured on concrete elements in practice with this new cell are much more reliable than those measured with the traditional Karsten-cell.
Schutzbehandlung von Beton mit Silan- und Siloxanpräparaten / Protective Treatment of Concrete with Silane or Siloxane
Authors: Nyman B. 
Published: November 2014

Abstract
By means of laboratory experiments it is shown that the penetration depth of a treatment of concrete with Silane depends strongly on the duration of suction and on the moisture content of the concrete. The necessary duration of suction can be estimated for any required penetration depth.
Bestimmung der Haftzugfestigkeit dichter Beschichtungen / Determination of bond strength of impermeable polymer coatings
Authors: Frey R.M. , Wittmann F.H. 
Published: November 2014

Abstract
In many cases there is a risk for the formation of blisters if impermeable polymer coatings are applied on porous substrates. On covers of courses in sport stadiums formation of blisters has been observed recently. In this contribution a method is described which can be used to investigate the causes of blister formation in a given system. Blisters are artificially created by the application of a gas pressure in the interface between coating and substrate. In this way the growth of blisters can be varied under controlled conditions. The theoretical background of this method is outlined. In this way it is possible to estimate the necessary pressure under the cover to create blisters of the observed size.
Neue kostengünstige rostfreie Stähle für den Einsatz bei korrosionsgefährdeten Stahlbetontragwerken / New and inexpensive stainless steels for use in reinforced concrete structures in agressive environment
Authors: Rechsteiner A. , Speidel M. O. 
Published: November 2014

Abstract
Stainless steel is essentially applied in structural elements in which chemical and mechanical loads are combined and which hardly allow periodic checks. Fixations are typical examples. In case of failure dramatic consequences have to be expected. This is also valid for steel reinforcement in concrete. It is exposed to combined chemical and mechanical load, it can hardly be controled and damage leads at least to enormous costs of repair. Due to the fact that up to now the expenditures for construction are rarely considered together with the expenditures for maintenance, the use of stainless steel is still exceptional. If it is possible, however, to produce cheap steel with a corrosion resistance comparable to steel 1.4401 or even better, wide spread use of stainless steel as concrete reinforcement should be possible. New types of austenitic and duplex steel as being developed in the Laboratory for metal research of Swiss Federal Institute of Technolog (ΕΤΗ) in Zurich without Ni seem to be promising materials. In this case it is tried to replace expensive components by cheap ones such as nitrogen.
Prediction of Durability of Concrete in Monuments using Fracture Mechanics / Vorhersage der Dauerhaftigkeit von Beton in Baudenkmalen durch Anwendung der Bruchmechanik
Authors: Leonovich S.N. 
Published: November 2014

Abstract
The extension of cracks and pores are considered to be a theoretical basis for the prediction of durability of concrete of monuments. For this purpose a two-level structural model has been introduced: (I) matrix of hardened cement paste with fine and coarse aggregates, (2) voids and cracks created by external actions. The main parameter of this approach is the critical stress intensity factor: [xxx] The stress intensity factor of the material in the vicinity of the crack tip governs the crack growth. If all micro- and macro-defects are taken into consideration on the different levels of the hierarchic structural system, it is possible to formulate the global response. Each pore or crack creates a characteristic stress field around its­ elf in the material. If these pores are classified into periodic volume elements, the individual stress fields can be superimposed. This results in the complex state of stress under an imposed deformation.
On-site and Laboratory Investigation of Materials and Structure of a Belltower in Monza / Untersuchungen an den Werkstoffen und am Tragwerk im Labor und am Objekt am Beispiel eines Glockenturms in Monza
Authors: Binda L. , Tiraboschi C. , Folli R. Tongini 
Published: November 2014

Abstract
After the collapse of some heavy buildings and towers in Italy and elsewhere, the hypothesis of possible continuous damage to these structures due to the dead weight and cyclic loads (wind, temperature variations, etc.) has been formulated by the authors. The long term behaviour of historic masonry has also been detected by laboratory creep and cyclic tests. The results indicate that a laboratory and on site investigation together with analytical modelling are important particularly for tall bell-towers. The application of these procedures on the Bell-Tower of the Cathedral of Monza is here reported and discussed
Spannungsrißkorrosion von Spannstahl - Vorstellung einer neuen Untersuchungsmethode / Stress corrosion of prestressing steel reinforcement - Presentation of a new test method
Authors: König G. , Krumbach R. , Heyn A. 
Published: November 2014

Abstract
The origin of the susceptiblility of prestressing steel reinforcement with respect to stress corrosion and the observed failure mechanisms can be described 'in detail. So far, however, no precise method exists to determine the sensitivity of prestressing reinforcement or to distinguish different types of steel with respect to their susceptiblility for stress corrosion. This fact leads not only to prejudices in practice but also to additional safety measures (f.e. robust reinforcement), which implies economical consequences. The aim of a cooperation project between the Institute of Concrete Structures and Building Materials Technology at Leipzig University and the Institute for Materials Technology and Testing at Otto-von-Guericke- University Magdeburrg is to develop a general acceptable test method which provides us quickly with meaningful results. It turned out that the observation of electrochemical noise is a promising method to study stress corrosion of prestressing steel reinforcement. This method can be applied both in laboratory testing and under site conditions and can therefore also serve as a basis for corrosion monitoring.
Electrolytes in narrow pores / Electrolyten in engen Poren
Authors: Churaev N.V. , Setzer Μ.J. , Wowra О. , Reick Μ. 
Published: November 2014

Abstract
Mean electrolyte concentration Cm in narrow charged pores decreases as a result of repulsion of co-ions from charged walls. The theory of electrical double layers (EDL) was used for calculation of this effect in dependence on surface potential values Φ1 and concentration C0 of bulk electrolyte solutions. The calculations were limited to the case of 1-1 electrolytes and low values of surface potentials Φ1 when simple analytical solutions may be used. Mean concentration of chloride ions and neutral solution in narrow negatively charged slit pores of different thickness h was calculated in dependence on Φ1 and Debye radius values. It was shown that the effect is more pronounced in narrow pores at relatively high absolute values of surface potentials and at low concentration of a bulk solution. In narrow hydrophilic pores, a decrease in mean electrolyte concentration results from the effect of dielectric exclusion caused by decreasing values of dielectric constant of water ef. The calculations were performed using Born equation that relates the self-energy of ions W with the 8f values and ion radii. Comparing the results obtained with measured values of rejection coefficients of electrolyte solutions in reverse osmosis membranes, the dependence of £f values on pore sizes was calculated. Repulsive forces arising in narrow pores as a result of overlapping of EDL are calculated in dependence on slit thickness, bulk solution concentration and surface potentials in the framework of the theory of electrostatic component of disjoining pressure. In the case of hydrophilic silica systems molecular attraction forces and repulsive structural forces were also taken into account. The arising structural forces are caused by overlapping of boundary layers of water with modified structure
Anwendung einer geo-elektrischen Untersuchungsmethode für Mauerwerk im Rahmen eines Instandsetzungsvorhabens / Geo-Electrical Survey of Masonry for Restoration Projects
Authors: Venderickx K. , Van Gemert D. 
Published: November 2014

Abstract
Geo-electrical relative difference mapping is presented as a non-destructive evaluation technique for ancient masonry. The method allows to visualise the internal structure and condition of the masonry. The decision on the necessity and on the type and degree of consolidation or strengthening of the masonry wall can be based on the information, obtained from the mapping. The paper deals with the arrangement of the original measurements to make them suitable for engineering evaluation. Firstly a numerical model is presented to filter out the influence of geometrical boundary conditions: they distort the measurements, but are of no interest for the evaluation. Secondly the maps are calibrated, to eliminate the influence of measuring configuration, and moisture content. The calibration methods are presented, and applied on the resistivity measurements, executed at the restoration project of the building "Duke's Mills" (13th Century) at Aarschot (B).
Bestimmung der Wasser- und Salzgehaltsverteilung durch Kombination von NMR- und γ-Durchstrahlungsmessungen / Determination of water and salt content distributions by means of combined NMR- and γ-transmission measurement
Authors: Holm A. , Künzel H.M. 
Published: November 2014

Abstract
When a masonry loaded with salt is exposed to natural weather conditions there are occurring two interdependent mechanisms of transport: moisture- and salt transport. For the purpose of investigating these coupled processes, the Fraunhofer- Institute of Building Physics developed a measurement technique which allows a non-destructive determination of both water content distribution and salt content distribution in capillary porous building materials. This system includes two different nuclear physical measurement procedures: Nuclear Magnetic Resonance (NMR) and gamma-ray attenuation. The NMR unit produces a signal that depends just on the number of protons in the specimen. Because of this, the water content of the specimen is linked to the signal of the NMR-measurement. During a gamma-ray attenuation measurement salt and water content distribution are gauged simultaneously. The larger the density of the measured specimen is, the stronger is the attenuation of the gamma-rays when they pervade the matter. By combining the results of these two measurement methods it is possible to determine the salt and water content distribution simultaneously in a non-destructive way. From this profiles it is possible to draw conclusions in respect of the occurring transport processes and the correlative parameters such as for example capillary transport coefficients and water absorption coefficients of salt loaded building material. These results yield the preconditions for first concrete basic approaches to describe the coupled moisture and salt transport and furthermore the influence of the salt on the moisture transport. Lately numerous absorption tests on Sander Sandstone were carried out. The specimens sucked saline solutions of different salts and concentrations. After defined time steps the profiles of water and salt content were measured. Furthermore tests during the drying period were preformed on specimens loaded with defined saline solutions.
Kathodischer Korrosionsschutz für Stahlbetontragwerke unter Verwendung eines neuen leitfähigen Anstrichsystems / Cathodic Corrosion Protection of Steel Reinforced Concrete Structures with a New Conductive Composite Paint System
Authors: Schwarz W. 
Published: November 2014

Abstract
Corrosion of steel in concrete is one of the critical problems in civil engineering with regard to the durability of reinforced concrete structures. Cathodic protection (CP) of the steel rebars in concrete structures evolved during the past 25 years as a reliable method to extend the lifetime of reinforced concrete structures. During the CP operation, proportional to the applied protection current, acids are generated at the anode/concrete interface. This effect limits durability and performance of various CP-systems. This contribution describes a newly developed conductive composite paint for use as anode material, characterized by high durability at high current densities and easy applicability, and its practical application for the corrosion protection of a parking deck in Oslo.
Die Verwendung von Systemen zur dauernden Überwachung der Korrosion in neuen und bestehenden Stahlbetontragwerken / The Use of Permanent Corrosion Monitoring in New and Existing Reinforced Concrete Structures
Authors: Broomfield J.P. , Davies K. , Hladky K. 
Published: November 2014

Abstract
Corrosion monitoring systems consisting of linear polarisation, concrete resistivity and other probes have been installed in new structures to monitor durability and in existing structures to evaluate rehabilitation strategies such as corrosion inhibitor application and patch repairs. The types of sensors used, data collection techniques, results and interpretation are discussed.
Effect of silane coupling agent on the mechanical properties of nitrile butadiene rubber (NBR)/organophilic montmorillonite (OMMT) nanocomposites
Authors: Zhang Ru Liang , Zhao Li Fen , Huang Yu Dong , Liu Li 
Published: November 2014

Abstract
The effect of coupling agents on the mechanical properties of nitrile butadiene rubber (NBR)/organophilic montmorillonite (OMMT) clay nanocomposites was studied using three different types of silane coupling agents, which were γ-(aminopropyl)triethoxysilane, γ-(mercaptopropyl) triethoxy silane, and bis-[(γ-triethoxy silane)proply] tetrasulfur. The NBR/OMMT nanocomposites were prepared via the melt compounding with OMMT clay. The effect of silane coupling agents on the dispersion of OMMT in the polymer matrix was studied by X-ray diffraction. Dynamic mechanical analysis was employed to investigate the mechanical properties change induced by the silane coupling agents. The results suggest improved mechanical properties for the nanocomposites with coupling agents of γ-(mercaptopropyl) triethoxy silane and bis-[(γ-triethoxy silane)proply] tetrasulfur, whereas reduced mechanical properties were observed for nanocomposites with γ-(aminopropyl)triethoxysilane.
Modeling cement hydration by connecting a nucleation and growth mechanism with a diffusion mechanism. Part I: C3S hydration in dilute suspensions
Authors: Pang Xueyu , Meyer Christian 
Published: November 2014

Abstract
A particle-based C3S hydration model, which mathematically connects a nucleation and growth controlled mechanism with a diffusion controlled mechanism, is developed in this study. The model is first formulated and fitted with C3S hydration in stirred dilute suspensions in Part I where interactions between different particles can be ignored, and further developed and fitted with Portland cement paste hydration in Part II to account for inter-particle interactions. Excellent agreement was observed between experimental and modeled results. Three critical rate-controlling parameters, including a parallel growth rate constant, a perpendicular growth rate constant and a diffusion constant, were identified from the proposed model. The dependencies of these parameters on particle size and initial quantity of nuclei are investigated in Part I while their dependencies on cement composition, water-cement ratio, and curing condition are studied in Part II.
Electron Transfer Reaction of Ion Pairs: 1.  Surfactant Cobalt(III) Complexes by Fe(CN)6
4− in Microheterogeneous Media
Authors: Nagaraj Karuppiah , Senthil Murugan Krishnan , Thangamuniyandi Pilavadi 
Published: November 2014

Abstract
The kinetic study of reduction of single chain surfactant octahedral
cobalt(III) complexes,
cis-[Co(en)2(4AMP)(DA)](ClO4)3 and
cis-[Co(trien)(4CNP)(DA)](ClO4)3 (where
en = ethylenediamine; trien = triethylenetetramine;
4AMP = 4-aminopyridine; 4CNP = 4-cyanopyridine;
DA = dodecylamine) with [Fe(CN)6]4–
has been
carried out by spectrophotometric method under pseudo first order
conditions using an excess of a reductant in different media namely,
micelles, β-cyclodextrim (β-CD), liposome vesicles (DPPC)
and ionic liquids ((BMIM)Br) at different temperatures in order
to have deep insight into the molecular behavior during the electron
transfer reaction. The analysis of kinetic results strongly suggests
that the reduction reaction between the surfactant complex and
[Fe(CN)6]4–
occurs via a second order outer sphere
electron transfer mechanism. The remarkable increase in the rate of
electron transfer from the oxidant to reductant is observed in ionic
liquid medium as compared to the rest of all other media studied in
the present investigation. This can be ascribed due to the fact that
the formation of aggregated and constrained geometry of the surfactant
cobalt(III) complexes (oxidants) in ionic liquid medium renders the
rate of one electron transfer from the oxidants to the reductant,
[Fe(CN)6]4–
to be higher. Furthermore, the rate constant
value increases with increase in the concentration of micelles,
however in the presence of β-cyclodextrin medium the rate of
electron transfer substantially decreases due to the inclusion of long
aliphatic chain of the surfactant cobalt(III) complexes into
β-cyclodextrin. In liposome media, second order rate constant
for this electron transfer reaction from both the oxidants was found
to decrease with increase in the concentration of the liposome below
the phase transfer temperature of DPPC. However, above the phase
transition temperature the reaction was found to increase with
increase in the concentration of the DPPC. The main driving force for
this phenomenon is considered to be the intervesicular hydrophobic
interaction between the surfactant complexes and vesicular
surface. The activation parameters
(ΔS‡ and
ΔH‡)
of this outer sphere
electron transfer reaction have been calculated by varying
temperatures and the analysis of the data corroborates the kinetics of
the reaction.