Influence of Cement Types on Properties of Anti-spalling Silica Aerogel Mortar Modified HPC for Tunnel Fire Safety

Abstract

In order to develop the cement-based mortar protecting high performance concrete from spalling under tunnel fire, the influence of ordinary portland cement(PO) and high belite cement (HBC) on the SiO2 aerogel fireproof mortar performance was investigated. Using the volume method, the mortar mix proportion was designed, where the total volume of aerogel and sand was fixed to 60%, with a varying aerogel volume ratio of 0, 20, 40, 60 and 80%. The results indicated the PO aerogel mortar had compressive strength, flexural strength and water absorption of 12.8%, 41.8 % and 29.8% higher, and softening coefficient and thermal conductivity of 2.5% and 27.9% lower than HBC aerogel mortar.