<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>0379-3982</journal-id>
<journal-title><![CDATA[Revista Tecnología en Marcha]]></journal-title>
<abbrev-journal-title><![CDATA[Tecnología en Marcha]]></abbrev-journal-title>
<issn>0379-3982</issn>
<publisher>
<publisher-name><![CDATA[Instituto Tecnológico de Costa Rica]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0379-39822024000400171</article-id>
<article-id pub-id-type="doi">10.18845/tm.v37i4.6934</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Application of commercial sand aggregates in hydrophobized hydraulic concrete materials]]></article-title>
<article-title xml:lang=""><![CDATA[Utilización de arenas comerciales en materiales de concreto hidrofobizados]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Mora]]></surname>
<given-names><![CDATA[Ernesto]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Castellón]]></surname>
<given-names><![CDATA[Erick]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad de Costa Rica  ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Costa Rica</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Universidad de Costa Rica  ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Costa Rica</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>12</month>
<year>2024</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>12</month>
<year>2024</year>
</pub-date>
<volume>37</volume>
<numero>4</numero>
<fpage>171</fpage>
<lpage>183</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.sa.cr/scielo.php?script=sci_arttext&amp;pid=S0379-39822024000400171&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.sa.cr/scielo.php?script=sci_abstract&amp;pid=S0379-39822024000400171&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.sa.cr/scielo.php?script=sci_pdf&amp;pid=S0379-39822024000400171&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Abstract Because precursors such as sand are generally accessible, concrete has become a widely used construction material. Not all available sands, however, fulfill the requirements of purity, granulometry, shape and porosity for use in concrete materials. Here we report the setting of the hydrophobicity of hydraulic concrete matrices prepared with commercial sands and hydrophobic silica particles (dodecyl-modified silica) added to their mixtures. The granulometry and porosity of the selected fine aggregates were confirmed to influence the water absorption of hydrophobized concrete matrices. Water absorption decreased more than 30 % on addition of silica hydrophobized with dodecyl. As the functionalization was performed from the mix prepared with commercial sands, an improved hydrophobicity of the materials was provided integrally to the matrix.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen El concreto hidráulico es uno de los materiales de construcción más empleados debido a la ubicuidad de sus precursores: agua, cemento, agregados finos y gruesos. Uno de los agregados principales es la arena, sin embargo, no todas las arenas disponibles cumplen los requisitos de idoneidad, pureza, graduación, forma y porosidad. Algunas soluciones para el mejoramiento de arenas para su uso en la fabricación de concreto hidráulico son la combinación de agregados finos, uso de aditivos, alternativas de reemplazo e incremento en la cantidad de cemento, entre otras posibilidades remediales. Este artículo describe la formulación de materiales de concreto hidrofóbicos con tres tipos de arenas (con porosidades, granulometrías y finuras diferenciadas entre sí). La hidrofobización del concreto se realiza al incorporar partículas de sílices modificadas químicamente y se estudia la interacción de estas partículas con las diferentes arenas. Se confirmó que la graduación y la porosidad de los agregados finos seleccionados influye en la absorción de agua de las matrices de concreto, sin embargo, se logra una mejora de más del 30% en la hidrofobicidad de la matriz al agregar sílice hidrofóbica.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[Concrete matrix]]></kwd>
<kwd lng="en"><![CDATA[hydrophobic particles]]></kwd>
<kwd lng="en"><![CDATA[porous-media]]></kwd>
<kwd lng="en"><![CDATA[characterization]]></kwd>
<kwd lng="en"><![CDATA[water transport]]></kwd>
<kwd lng="es"><![CDATA[Caracterización de arenas]]></kwd>
<kwd lng="es"><![CDATA[concreto]]></kwd>
<kwd lng="es"><![CDATA[partículas hidrofóbicas]]></kwd>
<kwd lng="es"><![CDATA[matriz]]></kwd>
<kwd lng="es"><![CDATA[porosidad]]></kwd>
<kwd lng="es"><![CDATA[transporte de agua]]></kwd>
</kwd-group>
</article-meta>
</front><back>
<ref-list>
<ref id="B1">
<label>(1)</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Mindess]]></surname>
<given-names><![CDATA[S.]]></given-names>
</name>
</person-group>
<source><![CDATA[Developments in the Formulation and Reinforcement of Concrete]]></source>
<year>2019</year>
</nlm-citation>
</ref>
<ref id="B2">
<label>(2)</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Ding and X. Ning]]></surname>
<given-names><![CDATA[Y.]]></given-names>
</name>
</person-group>
<source><![CDATA[Reinforced Concrete]]></source>
<year>2022</year>
</nlm-citation>
</ref>
<ref id="B3">
<label>(3)</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Surahyo. Concrete Construction. Cham]]></surname>
<given-names><![CDATA[A.]]></given-names>
</name>
</person-group>
<source><![CDATA[Concrete Construction]]></source>
<year>2019</year>
</nlm-citation>
</ref>
<ref id="B4">
<label>(4)</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Yang]]></surname>
<given-names><![CDATA[W.]]></given-names>
</name>
</person-group>
<source><![CDATA[The Issues and Discussion of Modern Concrete Science. Berlin]]></source>
<year>2015</year>
</nlm-citation>
</ref>
<ref id="B5">
<label>(5)</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Janamian and J. Aguiar]]></surname>
<given-names><![CDATA[K.]]></given-names>
</name>
</person-group>
<source><![CDATA[Concrete Materials and Technology. London, UK: CRC Press, 2023.]]></source>
<year>2023</year>
</nlm-citation>
</ref>
<ref id="B6">
<label>(6)</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Jiang]]></surname>
<given-names><![CDATA[Z.]]></given-names>
</name>
</person-group>
<source><![CDATA[Performance Concrete with Manufactured Sand]]></source>
<year>2023</year>
</nlm-citation>
</ref>
<ref id="B7">
<label>(7)</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Lesage]]></surname>
<given-names><![CDATA[K.]]></given-names>
</name>
</person-group>
<source><![CDATA[Active Rheology Control of Cementitious Materials]]></source>
<year>2023</year>
</nlm-citation>
</ref>
<ref id="B8">
<label>(8)</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Gaganelis]]></surname>
<given-names><![CDATA[G.]]></given-names>
</name>
<name>
<surname><![CDATA[Mark]]></surname>
<given-names><![CDATA[P.]]></given-names>
</name>
<name>
<surname><![CDATA[Forman]]></surname>
<given-names><![CDATA[P.]]></given-names>
</name>
</person-group>
<source><![CDATA[Optimization Aided Design]]></source>
<year>2022</year>
</nlm-citation>
</ref>
<ref id="B9">
<label>(9)</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Hewlett]]></surname>
<given-names><![CDATA[P.]]></given-names>
</name>
<name>
<surname><![CDATA[Liska]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
</person-group>
<source><![CDATA[Lea's Chemistry of Cement and Concrete]]></source>
<year>2019</year>
</nlm-citation>
</ref>
<ref id="B10">
<label>(10)</label><nlm-citation citation-type="">
<source><![CDATA[Practical Concrete Mix Design]]></source>
<year>2020</year>
</nlm-citation>
</ref>
<ref id="B11">
<label>(11)</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Torrent]]></surname>
<given-names><![CDATA[R.]]></given-names>
</name>
<name>
<surname><![CDATA[Neves]]></surname>
<given-names><![CDATA[R.]]></given-names>
</name>
<name>
<surname><![CDATA[Imamoto]]></surname>
<given-names><![CDATA[K.]]></given-names>
</name>
</person-group>
<source><![CDATA[Concrete Permeability and Durability Performance]]></source>
<year>2022</year>
</nlm-citation>
</ref>
<ref id="B12">
<label>(12)</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Zhou]]></surname>
<given-names><![CDATA[X.]]></given-names>
</name>
<name>
<surname><![CDATA[Hou]]></surname>
<given-names><![CDATA[D.]]></given-names>
</name>
</person-group>
<source><![CDATA[Advanced Concrete Technology]]></source>
<year>2023</year>
</nlm-citation>
</ref>
<ref id="B13">
<label>(13)</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Kosmatka]]></surname>
<given-names><![CDATA[S.]]></given-names>
</name>
<name>
<surname><![CDATA[Wilson]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
</person-group>
<source><![CDATA[Design and Control of Concrete Mixtures]]></source>
<year>2016</year>
</nlm-citation>
</ref>
<ref id="B14">
<label>(14)</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Moulay-Alia]]></surname>
<given-names><![CDATA[A.]]></given-names>
</name>
<name>
<surname><![CDATA[Abdeldjalila]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
<name>
<surname><![CDATA[Khelafib]]></surname>
<given-names><![CDATA[H.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[An experimental study on the optimal compositions of ordinary concrete based on corrected dune sand&#8212;Case of granular range of 25 mm. Case Studies in Construction]]></article-title>
<source><![CDATA[Materials]]></source>
<year>2021</year>
</nlm-citation>
</ref>
<ref id="B15">
<label>(15)</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Gou]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
<name>
<surname><![CDATA[Xing]]></surname>
<given-names><![CDATA[F.]]></given-names>
</name>
<name>
<surname><![CDATA[Zhou]]></surname>
<given-names><![CDATA[X.]]></given-names>
</name>
<name>
<surname><![CDATA[Sun]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
<name>
<surname><![CDATA[Sui]]></surname>
<given-names><![CDATA[L.]]></given-names>
</name>
<name>
<surname><![CDATA[Zhou]]></surname>
<given-names><![CDATA[Y.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Characterization of mechanical properties of eco-friendly concrete made with untreated sand and seawater based on statistical analysis. water absorption in concrete materials by modification with hybrid hydrophobic silica particles]]></article-title>
<source><![CDATA[Construction and Building Materials]]></source>
<year>2019</year>
</nlm-citation>
</ref>
<ref id="B16">
<label>(16)</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Kaufmann]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Evaluation of the combination of desert sand and calcium sulfoaluminate cement for the production of concrete]]></article-title>
<source><![CDATA[Construction and Building Materials]]></source>
<year>2020</year>
</nlm-citation>
</ref>
<ref id="B17">
<label>(17)</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Steyn]]></surname>
<given-names><![CDATA[Z.]]></given-names>
</name>
<name>
<surname><![CDATA[Babufem]]></surname>
<given-names><![CDATA[A.]]></given-names>
</name>
<name>
<surname><![CDATA[Fataar]]></surname>
<given-names><![CDATA[H.]]></given-names>
</name>
<name>
<surname><![CDATA[Combrinck]]></surname>
<given-names><![CDATA[R.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Concrete containing waste glass, plastic and rubber as sand replacement]]></article-title>
<source><![CDATA[Construction and Building Materials]]></source>
<year>2021</year>
</nlm-citation>
</ref>
<ref id="B18">
<label>(18)</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Mora]]></surname>
<given-names><![CDATA[E.]]></given-names>
</name>
<name>
<surname><![CDATA[González]]></surname>
<given-names><![CDATA[G.]]></given-names>
</name>
<name>
<surname><![CDATA[Romero]]></surname>
<given-names><![CDATA[P.]]></given-names>
</name>
<name>
<surname><![CDATA[Castellón]]></surname>
<given-names><![CDATA[E.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Control of water absorption in concrete materials by modification with hybrid hydrophobic silica particles]]></article-title>
<source><![CDATA[Construction and Building Materials]]></source>
<year>2019</year>
</nlm-citation>
</ref>
<ref id="B19">
<label>(19)</label><nlm-citation citation-type="">
<collab>ASTM (American Society for Testing and Materials)</collab>
<source><![CDATA[Standard Specification for Concrete Aggregates ASTM International]]></source>
<year>2018</year>
</nlm-citation>
</ref>
<ref id="B20">
<label>(20)</label><nlm-citation citation-type="">
<source><![CDATA[Standard Test Method for Relative Density (Specific Gravity) and Absorption of Fine Aggregate]]></source>
<year>2015</year>
</nlm-citation>
</ref>
<ref id="B21">
<label>(21)</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Schneider]]></surname>
<given-names><![CDATA[P.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Adsorption isotherms of microporous-mesoporous solids revisited]]></article-title>
<source><![CDATA[Appl. Catal. A: General]]></source>
<year>1995</year>
</nlm-citation>
</ref>
<ref id="B22">
<label>(22)</label><nlm-citation citation-type="">
<source><![CDATA[Standard Test Method for Compressive Strength of Hydraulic Cement Mortars (Using 2-in. or (50-mm) Cube Specimens)]]></source>
<year>2020</year>
</nlm-citation>
</ref>
<ref id="B23">
<label>(23)</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Mora]]></surname>
<given-names><![CDATA[E.]]></given-names>
</name>
<name>
<surname><![CDATA[Castellón]]></surname>
<given-names><![CDATA[F.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Anti-adherent molds yield hydraulic concrete samples suitable for assessments of surface and water absorption]]></article-title>
<source><![CDATA[Journal of Civil Engineering and Construction]]></source>
<year>2021</year>
</nlm-citation>
</ref>
<ref id="B24">
<label>(24)</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Stalder]]></surname>
<given-names><![CDATA[A.]]></given-names>
</name>
<name>
<surname><![CDATA[Kulik]]></surname>
<given-names><![CDATA[G.]]></given-names>
</name>
<name>
<surname><![CDATA[Sage]]></surname>
<given-names><![CDATA[D.]]></given-names>
</name>
<name>
<surname><![CDATA[Barbieri]]></surname>
<given-names><![CDATA[L.]]></given-names>
</name>
<name>
<surname><![CDATA[Hoffmann]]></surname>
<given-names><![CDATA[P.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[A snake-based approach to accurate determination of both contact points and contact angles]]></article-title>
<source><![CDATA[Colloid, Surface]]></source>
<year>2006</year>
</nlm-citation>
</ref>
<ref id="B25">
<label>(25)</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Walton and R. Snurr]]></surname>
<given-names><![CDATA[K.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Applicability of BET Method for Determining Surface Areas of Microporous Metal-Organic Frameworks]]></article-title>
<source><![CDATA[J. Am. Chem. Soc]]></source>
<year>2007</year>
</nlm-citation>
</ref>
<ref id="B26">
<label>(26)</label><nlm-citation citation-type="journal">
<article-title xml:lang=""><![CDATA[Langmuir-type model for anomalous moisture diffusion in composite resins]]></article-title>
<source><![CDATA[Journal Composite Materials]]></source>
<year>1978</year>
</nlm-citation>
</ref>
</ref-list>
</back>
</article>
