Title:
Development of Wet-Mix Shotcrete with Portland Limestone Cement (Prepublished)
Author(s):
Lihe (John) Zhang, Matthew Zhang., Dudley R. (Rusty) Morgan, and Sidney Mindess
Publication:
Materials Journal
Volume:
Issue:
Appears on pages(s):
Keywords:
alkali-free accelerator, early age compressive strength development, flexural toughness, ground support, Portland limestone cement, residual tensile strength, shotcrete, Type GUL, Type IL
DOI:
10.14359/51749444
Date:
1/12/2026
Abstract:
Portland limestone cement (PLC) is being more and more specified and used in wet-mix shotcrete construction for ground support in tunnels and mines across the USA and Canada. The most widely used cement of Type GU (general use) in Canada and Type I in the USA is being replaced by Type GUL (general use limestone) in Canada and Type IL in the USA. There is no significant research being conducted on the performance of shotcrete made using PLC, including plastic properties, early age strength development, compressive strength development and, when fibers are added, flexural toughness and residual tensile strength development. This paper presents studies on the properties of wet-mix shotcrete produced with PLC. Results show that PLC requires a higher dosage of alkali-free accelerator (AFA) to achieve similar development of early age compressive strength compared to shotcrete made with PC. Development of compressive strength at 7 and 28 days for shotcrete made with PLC is similar to shotcrete made with PC. When both steel fibers and macrosynthetic fibers are used in wet-mix shotcrete made with PLC, development of residual tensile strength with notched beams and flexural toughness for round determinate panels is also similar to that for wet-mix shotcrete produced with PC. Future research on wet-mix shotcrete with Type GUL cement is also discussed.