Title:
Shotcrete Test Center
Author(s):
Espen A Rudberg and Thomas Beck
Publication:
Symposium Paper
Volume:
303
Issue:
Appears on pages(s):
183-190
Keywords:
shotcrete; test center; alkali free shotcrete accelerator; compression strength development; fresh concrete temperature; curing temperature
DOI:
10.14359/51688133
Date:
6/1/2015
Abstract:
Early compressive strength development in sprayed concrete is a crucial factor for success. A full scale mixing and spraying test have been done in Mapei’s Shotcrete Test Centre (STC) in Norway. Two identical batches of fresh concrete have been made, but with +13 °C (55.4 °F) and +28 °C (82.4 °F) fresh concrete temperature. Two sample boxes from each concrete batch have been sprayed with 9% alkali-free accelerator and have been stored in warm +20 °C (68 °F) and cold +5 °C (41 °F) conditions. A higher temperature in fresh concrete increased the compressive strength the first hour, while warmer conditions when curing had a stronger influence on the compressive strength at 6, 12 and 24 hour.