Wet shotcrete support is the main method for underground engineering construction at present. The rebound rate one of indicators to evaluate effect, and a lower will improve effect wet shotcrete. concrete aggregates available in different regions China have particle sizes. To achieve better supporting discrete element used simulate spraying process By constructing nozzle structure simplifying s...

Shotcrete is often in direct contact with groundwater containing sulfate. The resistance to sulfate attack of modern sprayed concretes produced non-alkali aluminate-based accelerators combination different cement types related their microstructure, transport properties, porosity and phase composition. A characterization these properties allows a comprehensive assessment the shotcrete identifica...

Abstract Rock–shotcrete structures are often suffered from dynamic shearing. However, the understanding of shear response rock–shotcrete is still at its infancy. To investigate effects strain rate and interface roughness on structure, laboratory tests were carried out modified double notched sandstone–concrete specimen. Testing results show that strength peak specimens both far less than those ...

When shotcrete is in contact with sulfate containing ground water, there a risk of drastically reduced service life. In this case, the use sulfate-resisting cement recommended. Since physical characteristics matrix differ from conventional concrete, cements do not always guarantee sufficient durability. Thus, testing resistance accelerated tests necessary. Providing test samples on-site (real) ...

Conventional bolt–shotcrete support technology is usually single-layered, which does not meet the requirements of strength and stiffness for roadway support. Therefore, in this paper, new combined technology, including a multiple-layered staggered dense arrangement bolts, laying steel meshes, pouring shotcrete, strengthening long cables, full cross-section grouting, proposed. Specifically, foll...

Abstract The reduction of clinker use is mandatory to lower the negative environmental impact concrete. In shotcrete mixes, similarly case conventional concrete, supplementary cementitious materials (SCMs) and proper mix design allow for substitution without compromising mechanical properties. However, on durability needs be further assessed understood. results from present study, obtained real...