Oladis Troconis de Rincón - Academia.edu (original) (raw)

Papers by Oladis Troconis de Rincón

Revista técnica de la Facultad de Ingeniería. Universidad del Zulia/Revista Técnica de la Facultad de Ingeniería, 2024

Materials Performance, Oct 1, 1996

The use of mortars based on portland cement and epoxy resins to repair corroded reinforced concre... more The use of mortars based on portland cement and epoxy resins to repair corroded reinforced concrete structures was evaluated by electrochemical techniques. The effect of surface preparation also was studied. Steel potentials were measured daily. Additionally, the degree of steel corrosion by linear polarization was measured at different stages of the process. When indications of corrosion were detected, the surface

Revista Tecnica De La Facultad De Ingenieria Universidad Del Zulia, Apr 1, 2004

Materials Performance, 2008

This article discusses the performance of thermal-sprayed Al, Zn, and Zn/Al coatings in the tropi... more This article discusses the performance of thermal-sprayed Al, Zn, and Zn/Al coatings in the tropical marine environments of Venezuela. The results showed that in these aggressive atmospheres, where the wind effect is high, the performance of thermal-sprayed Zn/Al with wash primer is excellent, providing galvanic protection to the substrate.

Revista Tecnica De La Facultad De Ingenieria Universidad Del Zulia, Dec 1, 2006

The obj ective of lhis researeh Is lo stu dy the effect tha t have pore sealers in the behavior o... more The obj ective of lhis researeh Is lo stu dy the effect tha t have pore sealers in the behavior of Thennal Sprayed Cinc y Aluminum. and Zn / Al coatings in marine and coastal m arine atm ospheres. durtng on e year of exposiUon. Tothat effect. carbon steel sh e ls (lOcm x 15cm x 3 mm) were sprayed by u sin g lwo dlf feren t proeesses (eleetric arch and Dame spray), with and withou t lhe a p pl1cation of lwo add itionallayers of sealer. Three ealers were evaluated: two wa sh primers of dlfferent suppliers. and a phenolic sealer. The sheets were exposed in two a tm ospheric tes t sites. La Voz (coastal marine a tmospb ere), and the Tow rs of t he crossing of the Lake of Marae ibo (martne atm osphere). The sheels were eharaeterized b y mean s of m i tia! weight. lhielrness. metallogr aph ic. adhes10n, rou ghness. being evaluated monthly by visu al m spec tion and photographic. The results showed that in lhese aggresslve atmos pheres. w here the wlnd effect is imp ortant. lbe thennal sprayed Zn/Al coating , orrers an excellent behavior even withou t sealer. produclng galvanic protecUon to the substrale. In the case of thennal sprayed of Cinc a n d Alumin um coatings. a phenolic based pore sealer s~o u ld be u s ed , for covering completely the irregularities owned by this typ e of coatlng. K ey words: Aluminum thennal sprayed. zinc lhenna! sprayed. a tmospheric corrosion, marine a tm ospheres. a ccelerated Lests. Efecto del s ellador de poros en el comportamiento de los recubrimientos por termorrociado de aluminio y cinc en atmósferas marinas y costero marinas Resumen El objetivo de este trabajo es estudiar el efecto que tiene u n sellador de poros en el comportamiento de los recubrim ientos p or tennorrociado d e cin c. alumin10 y Zn/ Al en atmosfera s marinas y c steras ma rinos, luego de 1 año de ex-posición. Para ello. se evalu aron láminas de acero al carbono (SAE 1010) de 10cm x 15em. tennorociadas por dos p rocesos diferentes de apUcación (arco eléctrlco y llama). con y sin la aplicación de dos capas adicionales de recubrimiento sellador orgánico. Se evaluaron tres s elladores: dos ~wash primer" de diferentes fabricantes, y u n sellador fenóUco. Las lámmas fueron expuestas en d os esta ciones de ensayo natural: La Voz (atmósfera costera marina). y Las Torres del cruce del Lago de Maracaib o (atmósfera marina). Las probetas se caracterizaron mediante m asa inicial, espesor, metalografia, adhe rencia y rugosidad. evaluándose mensualmente por inspección visual• Y registro fotognillco. Estas probe tas se retiraron a los 3. 6 Y 12 meses de exposición para s er analizad as en ellaboraiorto. Los Tesultados m ostraron que en los atmósferas a gresivos estudiados. don de el efecto erosivo es im p ortante, el recubrt mien to tennorrociado Zn / Al (doble capa). ofrece u n excelente comportamiento aún sin sellador y produce

Acta Microscopica, Nov 26, 2020

Revista Tecnica De La Facultad De Ingenieria Universidad Del Zulia, Jan 31, 2011

The obJeUve of the present Tcseach paper was to study the effect of appl1ed current to polar1Ze c... more The obJeUve of the present Tcseach paper was to study the effect of appl1ed current to polar1Ze cathodl ally lhe 1nner surface of tubes , to control sulphatc dcposlUons tn Heat Exchangers ustng sea water a a cool1ng fluJd. A T.1/ Pt anode was used to polartzc the tnl.emal surface of thc Al-brass ASTM B-lII type B lubes (3 / 4 In diamcter). Severa! experimental tests were ¡;un lo study the efflcJency of lhe systcm. In lhese. fue current applled was varled whUe kceplng both lhe fiow (Q) and lhe ouUel temperature (Ts) of!:he sea water steady. The scale samples fonned tn lhe pipes durlng each ofthe tests werc IdenUfied by X• Ray l1uorescence, chemJcal analysls of caUons and anlons and lurbldImetrlc analysls. The results show lhat up to 80 % of sulphate lons lo lhe scale can be Inh1blted. Jt was also found that the amounl of scale deposlted on thc , urface where the anode was localed 18 a funUon of the applled current: the lower lhe current the greater lhe lnhJblUon. However, the appUed currcnt produced no vartaUon on fue scale deposlUon in lhe area away from the anode 10caUon.

Corrosion Reviews, Dec 1, 2001

Rust scales of commercially available low carbon steels from Venezuela (A1S1 1010), Mexico and Cu... more Rust scales of commercially available low carbon steels from Venezuela (A1S1 1010), Mexico and Cuba (A1SI 1019) were characterised after exposure at two typical atmospheres in the Caribbean region: Merida (rural-urban; RU) and Progreso (marine-coastal; MC). Low carbon steel surfaces rusting in those atmospheres formed mainly the oxyhydroxides lepidocrocite (γ-FeOOH), goethite (α-FeOOH) and akaganeite (ß-FeOOH). Different amounts of lepidocrocite, goethite and akaganeite and the oxide phases hematite (a-Fe 2 0 3), magnetite (Fe 3 0 4) and maghemite (y-Fe 2 0 4) were found, depending on the deposition rates value of airborne salinity, time-of-wetness (TOW) and temperature present in every particular test site. The rust scale composition and air pollution are used to explain the corrosion rates and corrosion behaviour of the exposed low carbon steels in the tests sites. 435

Surface & Coatings Technology, 2005

Revista Técnica de la Facultad de Ingeniería Universidad del Zulia

In this work nine different coating systems, from national suppliers, were selected to perform th... more In this work nine different coating systems, from national suppliers, were selected to perform the evaluation in two severe tropical marine environments. New galvanized profiles as well as pre-exposed to the same environmental conditions were used as the test probes. Two different field stations were selected: La Voz and The Cross of Maracaibo Lake. Additionally, accelerated test were carried out in a station located at Centro de Estudios de Corrosión (CEC) by using the standard ISO 11474, and in the laboratory (PROHESION chamber). It is important to emphasize that after more than 36 month-exposure the behavior of the different coating systems on pre-exposed galvanized was clear, permitting to select the coating system with the best performance. Nevertheless in the case of new galvanized probes, after the evaluation period, most of the duplex systems had a very good performance.

Meeting abstracts/Meeting abstracts (Electrochemical Society. CD-ROM), Dec 22, 2023

DOAJ (DOAJ: Directory of Open Access Journals), Mar 1, 2011

Se estudio la factibilidad del uso de polarizacion catodica para prevenir la formacion de incrust... more Se estudio la factibilidad del uso de polarizacion catodica para prevenir la formacion de incrustaciones en intercambiadores de calor operados con agua de mar, por ser este el medio mas promisor, dadas las condiciones bajo las cuales cumplen su funcion estos intercambiadores. A tal efecto se disenaron dos sistemas de simulacion: un intercambiador de doble tubo, con el tubo exterior de resina epoxica y el tubo interior de laton de aluminio; y otro de tubo y carcaza, con el haz de tubos de laton al aluminio y la carcaza de acero al carbono. En ambos casos se aplico polarizacion catodica por corriente impresa, polarizando hasta varios potenciales de superficie. Las muestras de incrustaciones en ellos formadas se analizaron por difraccion de polvos de Rayos X y por turbidimetria, llegando a la conclusion de que es posible lograr mediante este metodo, inhibir completamente el proceso de formacion de incrustaciones de sulfatas o en su defecto, que estas esten formadas unicamente por depositos de carbonato de calcio.

Revista CENIC. Ciencias Químicas, 2015

RESUMEN. La corrosión del hormigón armado es la causa principal de las fallas y en consecuencia d... more RESUMEN. La corrosión del hormigón armado es la causa principal de las fallas y en consecuencia de pérdidas en la industria de la construcción. El medio marino es conocido como un entorno muy agresivo debido a que las sales transportadas por el viento son depositadas sobre la superficie del material metálico provocando su corrosión. Especímenes de concreto reforzados fueron elaborados con relaciones agua/cemento 0.45 y 0.65; estos se expusieron en un medio marino tropical en Campeche, México, a 300 m de la costa, cercano a una planta termoeléctrica, que libera dióxido de azufre. Este contaminante reacciona con la humedad y genera deposiciones ácidas. Las variables meteorológicas como: temperatura, humedad relativa, precipitación, dirección del viento, así como la concentración de dióxido de azufre y cloruro en la atmósfera fueron medidas durante siete años para relacionar su contribución al deterioro del hormigón. Además, se midieron parámetros electroquímicos como potencial de media celda, velocidad de corrosión y la resistividad eléctrica. Los resultados muestran que el proceso de corrosión no fue iniciado a pesar de una alta humedad relativa, temperatura, tiempo de humectación, concentración de cloruro y de dióxido de azufre. La buena propiedad de los especímenes se atribuye a la excelente calidad de los materiales, a la dosis correcta que se utilizó y el procedimiento adecuado de colado para la su elaboración, lo que les proporcionaron mayor durabilidad. ABSTRACT. Corrosion of reinforced concrete infrastructure is the principal cause of failures and consequently lost in construction industry. Marine environment is known as a very aggressive environment due to salts transported by the breeze is deposited over metallic materials surfaces and provoke their corrosion. Reinforced concrete specimens elaborated with water/cement ratios 0.45 and 0.65 were exposed to tropical marine environment at Campeche, Mexico, 300 m to coastline. In closeness, a thermoelectric plant is located, which releases sulfur dioxide, this pollutant reacts with humidity and generate acid depositions. Meteorological variables as temperature, relative humidity, precipitation, wind direction as well as chloride and sulfur dioxide concentration in atmosphere were monitored seven years to relate their contribution to concrete deterioration. Besides, electrochemical parameters as half-cell potential, corrosion rate and electrical resistivity were measured. Results show that in spite of high relative humidity, temperature and humectation time, chloride and sulfur dioxide concentration, the corrosion process, determined by electrochemical techniques, have not started. Good properties of specimens are attributed to excellent quality of materials utilized and correct dosage used to elaborate them, which provide them durability.

DOAJ (DOAJ: Directory of Open Access Journals), Jul 1, 2012

The purpose of this study is to differentiate the corrosive aggressiveness on iron of two predomi... more The purpose of this study is to differentiate the corrosive aggressiveness on iron of two predominant types of Sulphate Reducing Bacteria: SRB, Desulfovibrio (D) desulfuricans and D. termitidis, found in the injection waters frequently, using measurement of open circuit potential, ohmic drop, weight loss, Tafel polarization, polarization resistance and electrochemical impedance. The attack morphology was also studied over time through optical and scaning electron microscopes, every 3 hours during 24 hours. Additionally, a comparison was made among the different electrochemical techniques applied to establish which of these is the most appropriate and reliable for evaluating MIC processes. Results obtained showed values of weight loss and corrosion rate increasing up to 9 hours, at which time they began to decrease, reaching a minimum close to 15 hours of exposure, and then increasing up to the end of the experiment at 24 hours, with D. termitidis always demonstrating greater aggressiveness, a fact corroborated by observed the attack morphology. Of the techniques used for measuring corrosion rate, it was established that weight loss and Tafel polarization reflect most appropriately the best behavior of iron exposed to a medium inoculated with sulfate-reducing bacteria (SRB) and ferrous ions.

Anti-corrosion Methods and Materials, Feb 1, 2003

Exotic marine organisms, Garveia Franciscana, called "Pelo de Oso" by the locals, were detected i... more Exotic marine organisms, Garveia Franciscana, called "Pelo de Oso" by the locals, were detected in Lake Maracaibo. "Pelo de Oso" constitutes one of the three components of the metal/biota/solution system that interact in Lake Maracaibo, producing biofouling and microbiological corrosion. The latter generates great economic problems, mainly: water-pump failures. The objective of this paper was to determine the preference of these bioorganisms for materials, when immersed in Lake Maracaibo.

Revista Tecnica De La Facultad De Ingenieria Universidad Del Zulia, 1983

... IESlSll ~IC1A UilICAC10tl 1~/pi ... ) liLA " rn 48 ~I'HESIOrI Seco Seco So. Hora3 I... more ... IESlSll ~IC1A UilICAC10tl 1~/pi ... ) liLA " rn 48 ~I'HESIOrI Seco Seco So. Hora3 IKglcml¡ Al horno perf1etal ~.9 1"~.4 152." z.,po.ta de 57~ 4.5 152.9 1"".5 pil. ... 6.2 ISO. 6 1"1.9 551 pUa 3l 119.0 141.~ 6.1' 153.11 147.0 4.6 205 Zapata de 152.6 6.0 229 'pila 120 144:~ 149.3 '141. ...

These proceedings, "The Repair and Rehabilitation of Reinforced Concrete Structures: The Sta... more These proceedings, "The Repair and Rehabilitation of Reinforced Concrete Structures: The State-of-the-Art", are from an International Seminar, Workshop and Exhibition sponsored by the National Science Foundation (NSF) and the Science and Technology Program (CYTED) held in May 1997 in Maracaibo, Venezuela. The NACE International Latin American Region Venezuelan Section; Venezuelan Corrosion Association (ASVENCOR); the Center for Hemispherical Cooperation (CoHemis), University of Puerto Rico; and the Center for Corrosion Studies\ Universidad del Zulia, Maracaibo, Venezuela jointly organized this workshop whose purpose was to present current international knowledge about reinforced concrete structures and to describe future directions and propose joint research projects for repair and rehabilitation of reinforced concrete structures. Eleven of the fifteen papers are contained in these proceedings covering topics in corrosion, service life, and new materials. Four papers cover diverse subjects such as concrete block deterioration, vibration measurements, stainless steel rebar behaviors, and diagnosis and repair procedures resulting from overloads on a concrete parking structure. Summaries of workshop discussions are presented in Spanish and English.

International Journal of Corrosion, 2012