Characterization of chemical properties, mechanical performance and durability of sprayed concrete

• Grant number: 17/00125-9
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: May 01, 2017
• End date: December 31, 2018
• Field of knowledge: Engineering - Civil Engineering - Construction Industry
• Agreement: Coordination of Improvement of Higher Education Personnel (CAPES)
• Principal Investigator: Antonio Domingues de Figueiredo
• Grantee: Renan Pícolo Salvador
• Host Institution: Escola Politécnica (EP). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The compatibility between cement and accelerator is one of the most important parameters that control kinetics of hydration and the rate of mechanical strength gain in sprayed cementitious matrices. These factors are crucial for the stabilization of underground constructions during their execution and to evaluate the durability of the matrix. Although the sprayed concrete technology has advanced considerably over the past years, questions regarding its performance, efficient use and optimized mix design continue to arise. One of the main subjects that requires research is the characterization of the hydration behavior of accelerated cementitious matrices. The influence of accelerator reactions on the mechanical properties and durability of the matrix at short and long term also needs to be evaluated. In this context, a study covering these demands is proposed in this research project. The first subject covers the characterization of the kinetics and mechanisms of hydration and the microstructure of accelerated cement pastes. After that, the mechanical properties and the durability of sprayed concrete against external sulfate attack will be evaluated and correlated with the chemical properties of the matrix. As a complement, a thermodynamic analysis of the hydration of accelerated cement pastes will be performed to predict the hydration behavior of each mix based on the chemical composition of cements and accelerators. Results expected to be obtained will allow the elucidation of the main chemical processes occurring during accelerator reaction and further cement hydration and their influence on the mechanical strength and durability of the matrix. This research project may serve as a reference for the selection of compatible materials to obtain an optimized and more efficient accelerated matrix, with better mechanical properties and lower environmental impact. (AU)

Scientific publications

(8)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

RIBEIRO SIMAO, LUANA DE CARVALHO; NOGUEIRA, ANDRE BALTAZAR; MONTE, RENATA; SALVADOR, RENAN P.; DE FIGUEIREDO, ANTONIO DOMINGUES. Influence of the instability of the double punch test on the post-crack response of fiber-reinforced concrete. CONSTRUCTION AND BUILDING MATERIALS, v. 217, p. 185-192, AUG 30 2019. (17/00125-9)

SALVADOR, RENAN P.; RAMBO, DIMAS A. S.; BUENO, ROBERTO M.; SILVA, KAIO T.; DE FIGUEIREDO, ANTONIO D.. On the use of blast-furnace slag in sprayed concrete applications. CONSTRUCTION AND BUILDING MATERIALS, v. 218, p. 543-555, SEP 10 2019. (17/00125-9, 14/50948-3)

SERAFINI, RAMOEL; DANTAS, SERGIO R. A.; SALVADOR, RENAN P.; AGRA, RONNEY R.; RAMBO, DIMAS A. S.; BERTO, ANTONIO F.; DE FIGUEIREDO, ANTONIO D.. Influence of fire on temperature gradient and physical-mechanical properties of macro-synthetic fiber reinforced concrete for tunnel linings. CONSTRUCTION AND BUILDING MATERIALS, v. 214, p. 254-268, JUL 30 2019. (17/00125-9, 15/25457-9)

SERAFINI, RAMOEL; MENDES, LIVIA MOURAO; SALVADOR, RENAN PICOLO; DE FIGUEIREDO, ANTONIO DOMINGUES. The effect of elevated temperatures on the properties of cold-drawn steel fibres. MAGAZINE OF CONCRETE RESEARCH, v. 73, n. 18, p. 936-944, SEP 2021. (17/00125-9)

HERRERA-MESEN, C.; SALVADOR, R. P.; IKUMI, T.; CAVALARO, S. H. P.; AGUADO, A.. External sulphate attack of sprayed mortars with sulphate-resisting cement: Influence of accelerator and age of exposition. CEMENT & CONCRETE COMPOSITES, v. 114, p. 14-pg., 2020-11-01. (17/00125-9)

SALVADOR, RENAN P.; RAMBO, DIMAS A. S.; BUENO, ROBERTO M.; LIMA, SILVIO R.; FIGUEIREDO, ANTONIO D.. Influence of accelerator type and dosage on the durability of wet-mixed sprayed concrete against external sulfate attack. CONSTRUCTION AND BUILDING MATERIALS, v. 239, APR 10 2020. (17/00125-9)

HERRERA-MESEN, C.; SALVADOR, R. P.; CAVALARO, S. H. P.; AGUADO, A.. Effect of gypsum content in sprayed cementitious matrices: Early age hydration and mechanical properties. CEMENT & CONCRETE COMPOSITES, v. 95, p. 81-91, JAN 2019. (17/00125-9)

SERAFINI, RAMOEL; AGRA, RONNEY R.; SALVADOR, RENAN P.; DE LA FUENTE, ALBERT; DE FIGUEIREDO, ANTONIO D.. Double Edge Wedge Splitting Test to Characterize the Design Postcracking Parameters of Fiber-Reinforced Concrete Subjected to High Temperatures. JOURNAL OF MATERIALS IN CIVIL ENGINEERING, v. 33, n. 5, MAY 1 2021. (17/00125-9)