IMPROVED PERMEABILITY MODEL FOR CONCRETE AT HIGH TEMPERATURE

摘要

A "dense" concrete with a low permeability shows an increased risk towards explosive spalling.Tests on the permeability of UHPC without PP-fibers added to the concrete showed a decrease of permeability in the temperature range of T=175°C-275°C compared to the initial value at room temperature.These observations are consistent with results presented by Schneider et al.(1989).Based on these results an improved permeability model for concrete at high temperatures as part of a Thermo-Hygro (TH)-model is developed.This paper presents the main results from tests on temperature dependent permeability of concrete as well as the development of an improved permeability model as part of a TH-model to compute pore pressure inside heated concrete.