@inproceedings{MittermayrGalanSaadeetal.2019, author = {Mittermayr, Florian and Galan, Isabel and Saade, Marcella Ruschi Mendes and Saxer, Andreas and Kusterle, Wolfgang}, title = {"ASSpC" Shotcrete research for the needs of tomorrow}, series = {ICCC 2019: 15th International Congress on the Chemistry of Cement, ICCC 2019, 16.-20.09.2019, Prague, Czech Republik}, booktitle = {ICCC 2019: 15th International Congress on the Chemistry of Cement, ICCC 2019, 16.-20.09.2019, Prague, Czech Republik}, pages = {3518 -- 3872}, year = {2019}, abstract = {Shotcrete or sprayed concrete in tunneling in connection with the "New Austrian Tunneling Method" has been developed over the last decades to reach a high quality standard. However, at present the development of new shotcrete mixes is required to fulfill durability and stainability requirements, i.e. for superior performance in aggressive environments and reduction of maintenance costs. In the course of the project ASSpC ("Advanced and sustainable sprayed concrete") the research team focuses on producing and testing new and innovative shotcrete mixes using local and environmentally friendly raw materials. Sustainable and durable shotcrete with optimized mechanical and physical properties and improved chemical resistance is developed. This paper outlines the motivation for the project, gives an overview of the project structure and introduces key reaction mechanisms and environmental controls causing damage of shotcrete in tunnels.}, language = {en} } @inproceedings{SakoparnigGalanBaldermanetal., author = {Sakoparnig, Marlene and Galan, Isabel and Balderman, Andre and Steindl, Florian and Dietzel, Martin and Thumann, Maria and Saxer, Andreas and Kusterle, Wolfgang and Mittermayr, Florian}, title = {Experimental Ca leaching of shotcrete \& secondary precipitation}, series = {ICCC 2019: 15th International Congress on the Chemistry of Cement, ICCC 2019, 16.-20.09.2019, Prague, Czech Republik}, booktitle = {ICCC 2019: 15th International Congress on the Chemistry of Cement, ICCC 2019, 16.-20.09.2019, Prague, Czech Republik}, pages = {3488 -- 3495}, language = {en} } @inproceedings{ThumannJuhartRoecketal., author = {Thumann, Maria and Juhart, J. and R{\"o}ck, R. and Saxer, A. and Galan, Isabel and Mittermayr, F. and Kusterle, Wolfgang}, title = {Entwicklung neuer, dauerhafter und nachhaltiger Spritzbetone}, series = {Kolloquium Forschung \& Entwicklung f{\"u}r Zement und Beton 2018}, booktitle = {Kolloquium Forschung \& Entwicklung f{\"u}r Zement und Beton 2018}, pages = {65 -- 69}, language = {de} } @inproceedings{GalanGarciaStauffacherMittermayretal., author = {Galan Garcia, Isabel and Stauffacher, Anina and Mittermayr, Florian and Thumann, Maria and Kusterle, Wolfgang and Juilland, Patrick and Stenger, Christian and Lindlar, Benedikt}, title = {Estudio de las reacciones de hidrataci{\´o}n temprana en el hormig{\´o}n proyectado}, series = {HAC2018 - V Congreso Iberoamericano de Hormig{\´o}n Autocompactable y Hormigones Especiales ; Valencia 05.03.2018 - 06.03.2018}, booktitle = {HAC2018 - V Congreso Iberoamericano de Hormig{\´o}n Autocompactable y Hormigones Especiales ; Valencia 05.03.2018 - 06.03.2018}, publisher = {Universitat Polit{\`e}cnica Val{\`e}ncia}, isbn = {9788490485910}, doi = {10.4995/hac2018.2018.6907}, abstract = {El hormig{\´o}n proyectado es un tipo de hormig{\´o}n especial utilizado como soporte de rocas durante la construcci{\´o}n de t{\´u}neles y excavaci{\´o}n de minas, entre otras aplicaciones. Las principales caracter{\´i}sticas de este tipo de hormig{\´o}n son el fraguado r{\´a}pido y el desarrollo de una muy alta resistencia mec{\´a}nica a edades tempranas, lo cual permite que el hormig{\´o}n se fije a la base sin necesidad de un soporte extra, endureci{\´e}ndose en pocos minutos. Las reacciones de hidrataci{\´o}n que ocurren en las primeras horas en el hormig{\´o}n proyectado determinan el desarrollo de las propiedades mec{\´a}nicas y su estudio es de crucial importancia para entender y optimizar el comportamiento de este tipo de hormigones. El estudio de estas reacciones, sin embargo, resulta relativamente complicado por varias razones: (i) el hormig{\´o}n proyectado endurece muy r{\´a}pido, lo cual dificulta su manejo durante los ensayos experimentales, y (ii) composiciones similares mezcladas en el laboratorio no se comportan de forma similar a las proyectadas. En este trabajo se presenta una metodolog{\´i}a experimental desarrollada para el estudio de las reacciones de hidrataci{\´o}n que ocurren en el hormig{\´o}n proyectado durante las primeras horas y su correlaci{\´o}n con la resistencia mec{\´a}nica.}, language = {es} } @inproceedings{StauffacherGalanJuillandetal., author = {Stauffacher, Anina and Galan, Isabel and Juilland, Patrick and Thumann, Maria and Stenger, Christian and Baldermann, Andre and Mittermayr, Florian and Lindlar, Benedikt and Kusterle, Wolfgang}, title = {Einfluss von H{\"u}ttensand und ultrafeinem Kalksteinmehl auf die Hydratation von jungem Spritzbeton}, series = {Spritzbeton-Tagung 2018, Alpbach, Tirol, 11. und 12. Januar 2018. Tagungsbeitr{\"a}ge. CD-ROM}, booktitle = {Spritzbeton-Tagung 2018, Alpbach, Tirol, 11. und 12. Januar 2018. Tagungsbeitr{\"a}ge. CD-ROM}, editor = {Kusterle, Wolfgang}, address = {Oberperfuss}, subject = {Spritzbeton}, language = {de} } @article{GalanBaldermannKusterleetal., author = {Galan, Isabel and Baldermann, Andre and Kusterle, Wolfgang and Dietzel, Martin and Mittermayr, Florian}, title = {Durability of shotcrete for underground support}, series = {Construction and building materials}, volume = {202}, journal = {Construction and building materials}, number = {March}, publisher = {Elsevier}, doi = {10.1016/j.conbuildmat.2018.12.151}, pages = {465 -- 493}, abstract = {Shotcrete is often used for the construction and stabilization of tunnels and other underground structures, where it is susceptible to different forms of physical and chemical attacks affecting its durability. An advanced understanding of the factors that limit the durability of shotcrete is crucial to develop tailored strategies for enhancing its service life. The main focus of this contribution is to shed light on the durability of shotcrete by revising the literature, highlighting what is missing and needs to be addressed, assessing how the knowledge about concrete durability can be transferred to shotcrete, and providing recommendations for durable shotcrete structures. (C) 2018 Elsevier Ltd. All rights reserved.}, language = {en} } @inproceedings{SteindlMittermayrThumannetal., author = {Steindl, F. and Mittermayr, F. and Thumann, Maria and Juhart, J. and Galan Garcia, Isabel and Baldermann, Andre and Briendl, Lukas G. and Sakoparnig, M. and R{\"o}ck, Rudolf and Kusterle, Wolfgang}, title = {Sulfate resistance of dry mix shotcretes with new binder composition}, series = {ICCC 2019: 15th International Congress on the Chemistry of Cement, 16.-20.09.2019, Prague, Czech Republik}, booktitle = {ICCC 2019: 15th International Congress on the Chemistry of Cement, 16.-20.09.2019, Prague, Czech Republik}, pages = {3527 -- 3872}, abstract = {Improved understanding of the mechanisms underlying deleterious chemical attacks is necessary to better predict the long-term performance and durability of shotcrete in aggressive environments. In the scope of the research project "ASSpC - Advanced and Sustainable Sprayed Concrete", new durable and sustainable shotcretes and new test methods are developed. In order to increase shotcrete durability, the spray cement (specified in Austrian Guideline "Sprayed concrete") used is substituted with supplementary cementitious materials (SCMs). However, in the past SCMs have seen only limited use in the application of dry-mix shotcrete. This contribution presents 6 new mix designs intended to be used for dry-mix shotcrete, each with varying amounts and types of SCMs, and compares their performance and sprayability with a commercially available spray cement. As sulfate attack is one of the major threats to shotcrete (e.g. in tunnelling), the resistance of the new mixes against sulfate attack is tested using a modified version of the Swiss sulfate test according to SIA 262/1:2013. This approach provides new insights into damaging mechanisms of dry mix shotcrete in sulfate-loaded environments}, language = {en} } @article{GalanBriendlThumannetal., author = {Galan, Isabel and Briendl, Lukas G. and Thumann, Maria and Steindl, Florian and Roeck, Rudolf and Kusterle, Wolfgang and Mittermayr, Florian}, title = {Filler Effect in Shotcrete}, series = {Materials}, volume = {12}, journal = {Materials}, number = {19}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/ma12193221}, pages = {1 -- 24}, abstract = {The effects of fine limestone powder on the early hydration of cementitious systems accelerated by means of alkali-free aluminum sulfate based products, commonly used for shotcrete applications, were investigated in the course of laboratory and real scale tests. In binary (CEM I + limestone) and ternary (CEM I + limestone + slag) systems the addition of fine limestone led to an enhancement of the hydration degree and strength development at early times (<24 h). The formation of ettringite, aluminate hydrates, and C-S-H is affected by the joint action of the setting accelerator and the fine limestone. Accelerator and limestone, in combination with the cement, can be optimized to enhance ettringite and silicate reaction, in some cases coupled with aluminate reaction inhibition, to produce mixes suitable for sprayed concrete applications. Such optimization can help to reduce the cement content in the mixes without compromising the early strength development of the shotcrete.}, language = {en} } @inproceedings{BriendlGalanSteindletal., author = {Briendl, Lukas G. and Galan, Isabel and Steindl, Florian and R{\"o}ck, Rudolf and Thumann, Maria and Juhart, Joachim and Baldermann, Andre and Mittermayr, Florian and Kusterle, Wolfgang}, title = {Hydration processes of accelerated cementitious systems governing early strength development}, series = {ICCC 2019: 15th International Congress on Chemistry of Cement, 16.-20.09.2019, Prague, Czech Republik}, booktitle = {ICCC 2019: 15th International Congress on Chemistry of Cement, 16.-20.09.2019, Prague, Czech Republik}, pages = {714 -- 724}, language = {en} } @inproceedings{JuhartBriendlRoecketal., author = {Juhart, J. and Briendl, Lukas G. and R{\"o}ck, Rudolf and Galan, Isabel and Thumann, Maria and Mittermayr, F. and Kusterle, Wolfgang}, title = {Performance optimization of shotcrete by combined fillers}, series = {ICCC 2019: 15th International Congress on the Chemistry of Cement, ICCC 2019, 16.-20.09.2019, Prague, Czech Republik}, booktitle = {ICCC 2019: 15th International Congress on the Chemistry of Cement, ICCC 2019, 16.-20.09.2019, Prague, Czech Republik}, pages = {1387 -- 3872}, language = {en} }