TY - CHAP A1 - Mittermayr, Florian A1 - Galan, Isabel A1 - Saade, Marcella Ruschi Mendes A1 - Saxer, Andreas A1 - Kusterle, Wolfgang T1 - "ASSpC" Shotcrete research for the needs of tomorrow T2 - ICCC 2019: 15th International Congress on the Chemistry of Cement, ICCC 2019, 16.-20.09.2019, Prague, Czech Republik N2 - 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. Y1 - 2019 UR - https://iccc-online.org/fileadmin/gruppen/iccc/proceedings/ICCC15_2019.pdf SP - 3518 EP - 3872 ER - TY - CHAP A1 - Sakoparnig, Marlene A1 - Galan, Isabel A1 - Balderman, Andre A1 - Steindl, Florian A1 - Dietzel, Martin A1 - Thumann, Maria A1 - Saxer, Andreas A1 - Kusterle, Wolfgang A1 - Mittermayr, Florian T1 - Experimental Ca leaching of shotcrete & secondary precipitation T2 - ICCC 2019: 15th International Congress on the Chemistry of Cement, ICCC 2019, 16.-20.09.2019, Prague, Czech Republik Y1 - 2019 UR - https://iccc-online.org/fileadmin/gruppen/iccc/proceedings/ICCC15_2019.pdf SP - 3488 EP - 3495 ER - TY - CHAP A1 - Thumann, Maria A1 - Juhart, J. A1 - Röck, R. A1 - Saxer, A. A1 - Galan, Isabel A1 - Mittermayr, F. A1 - Kusterle, Wolfgang T1 - Entwicklung neuer, dauerhafter und nachhaltiger Spritzbetone T2 - Kolloquium Forschung & Entwicklung für Zement und Beton 2018 Y1 - 2018 UR - https://zement.at/downloads/downloads_2018/Kolloquium_Kurzbeitraege_2018_neu.pdf SP - 65 EP - 69 ER - TY - CHAP A1 - Galan Garcia, Isabel A1 - Stauffacher, Anina A1 - Mittermayr, Florian A1 - Thumann, Maria A1 - Kusterle, Wolfgang A1 - Juilland, Patrick A1 - Stenger, Christian A1 - Lindlar, Benedikt T1 - Estudio de las reacciones de hidratación temprana en el hormigón proyectado T2 - HAC2018 - V Congreso Iberoamericano de Hormigón Autocompactable y Hormigones Especiales ; Valencia 05.03.2018 - 06.03.2018 N2 - El hormigón proyectado es un tipo de hormigón especial utilizado como soporte de rocas durante la construcción de túneles y excavación de minas, entre otras aplicaciones. Las principales características de este tipo de hormigón son el fraguado rápido y el desarrollo de una muy alta resistencia mecánica a edades tempranas, lo cual permite que el hormigón se fije a la base sin necesidad de un soporte extra, endureciéndose en pocos minutos. Las reacciones de hidratación que ocurren en las primeras horas en el hormigón proyectado determinan el desarrollo de las propiedades mecánicas 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 hormigón proyectado endurece muy rápido, 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 metodología experimental desarrollada para el estudio de las reacciones de hidratación que ocurren en el hormigón proyectado durante las primeras horas y su correlación con la resistencia mecánica. Y1 - 2018 SN - 9788490485910 U6 - https://doi.org/10.4995/hac2018.2018.6907 PB - Universitat Politècnica València ER - TY - CHAP A1 - Stauffacher, Anina A1 - Galan, Isabel A1 - Juilland, Patrick A1 - Thumann, Maria A1 - Stenger, Christian A1 - Baldermann, Andre A1 - Mittermayr, Florian A1 - Lindlar, Benedikt A1 - Kusterle, Wolfgang ED - Kusterle, Wolfgang T1 - Einfluss von Hüttensand und ultrafeinem Kalksteinmehl auf die Hydratation von jungem Spritzbeton T2 - Spritzbeton-Tagung 2018, Alpbach, Tirol, 11. und 12. Januar 2018. Tagungsbeiträge. CD-ROM KW - Spritzbeton KW - Feuchtigkeit KW - Hydratation Y1 - 2018 CY - Oberperfuss ER - TY - JOUR A1 - Galan, Isabel A1 - Baldermann, Andre A1 - Kusterle, Wolfgang A1 - Dietzel, Martin A1 - Mittermayr, Florian T1 - Durability of shotcrete for underground support BT - Review and update JF - Construction and building materials N2 - 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. KW - CEMENT-BASED MATERIALS KW - CHEMOMECHANICAL COUPLING BEHAVIOR KW - Corrosion KW - Durability KW - FREEZE-THAW RESISTANCE KW - INDUCED CONCRETE CORROSION KW - Leaching KW - LEACHING BEHAVIOR KW - POLYPROPYLENE FIBERS KW - PORTLAND-CEMENT KW - POTENTIAL ALKALI-REACTIVITY KW - Shotcrete KW - Sintering KW - Sprayed concrete KW - Sulfate attack KW - THAUMASITE SULFATE ATTACK KW - Tunnel KW - Underground Y1 - 2019 U6 - https://doi.org/10.1016/j.conbuildmat.2018.12.151 VL - 202 IS - March SP - 465 EP - 493 PB - Elsevier ER - TY - CHAP A1 - Steindl, F. A1 - Mittermayr, F. A1 - Thumann, Maria A1 - Juhart, J. A1 - Galan Garcia, Isabel A1 - Baldermann, Andre A1 - Briendl, Lukas G. A1 - Sakoparnig, M. A1 - Röck, Rudolf A1 - Kusterle, Wolfgang T1 - Sulfate resistance of dry mix shotcretes with new binder composition T2 - ICCC 2019: 15th International Congress on the Chemistry of Cement, 16.-20.09.2019, Prague, Czech Republik N2 - 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 Y1 - 2019 SP - 3527 EP - 3872 ER - TY - JOUR A1 - Galan, Isabel A1 - Briendl, Lukas G. A1 - Thumann, Maria A1 - Steindl, Florian A1 - Roeck, Rudolf A1 - Kusterle, Wolfgang A1 - Mittermayr, Florian T1 - Filler Effect in Shotcrete JF - Materials N2 - 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. KW - acceleration KW - ACCELERATORS KW - ALKALI-FREE KW - ALUMINUM SULFATE KW - CaCO3 KW - CALCIUM-CARBONATE KW - CEMENT HYDRATION KW - EARLY AGE HYDRATION KW - hydration KW - LIMESTONE POWDER KW - mechanical properties KW - PORTLAND-CEMENT Y1 - 2019 U6 - https://doi.org/10.3390/ma12193221 VL - 12 IS - 19 SP - 1 EP - 24 PB - MDPI CY - Basel ER - TY - CHAP A1 - Briendl, Lukas G. A1 - Galan, Isabel A1 - Steindl, Florian A1 - Röck, Rudolf A1 - Thumann, Maria A1 - Juhart, Joachim A1 - Baldermann, Andre A1 - Mittermayr, Florian A1 - Kusterle, Wolfgang T1 - Hydration processes of accelerated cementitious systems governing early strength development T2 - ICCC 2019: 15th International Congress on Chemistry of Cement, 16.-20.09.2019, Prague, Czech Republik Y1 - 2019 SP - 714 EP - 724 ER - TY - CHAP A1 - Juhart, J. A1 - Briendl, Lukas G. A1 - Röck, Rudolf A1 - Galan, Isabel A1 - Thumann, Maria A1 - Mittermayr, F. A1 - Kusterle, Wolfgang T1 - Performance optimization of shotcrete by combined fillers T2 - ICCC 2019: 15th International Congress on the Chemistry of Cement, ICCC 2019, 16.-20.09.2019, Prague, Czech Republik Y1 - 2019 SP - 1387 EP - 3872 ER -