2.1 Raw materials
The 42.5 sulfoaluminate cement used for the test is offered by Tangshan
Polar Bear Building Materials Co., Ltd. Its chemical composition is
given in Table 1. Its physical properties are given in Table 2. The
foamer is HTW-1 composite protein foamer. The carbon fiber is offered by
Taili Carbon Fiber Co., Ltd., with a length of 3 mm and a fiber diameter
of 7 µm. The graphite is provided by Baichuan Environmental Engineering
Co., Ltd., with a grain size of 23 µm. The water reducing agent is a
powdered polycarboxylic acid water reducing agent. The hydroxypropyl
methylcellulose used for the test is offered by Jinzhou Fuqiang Fine
Chemical Co., Ltd. The tap water is adopted.