Curing Mechanism and Quality Evaluation of Unfired Hollow Brick With Shield Muck in Muddy Silty Clay Stratum

Aiming at the shield mucky silty clay soil in Hangzhou area, soil stabilizer and lime were used to reduce the moisture content of the mucky silty clay soil, and the influence on the strength of unfired hollow brick was determined. Based on the idea of uniform test, the influence of molding pressure, sodium silicate and lime on the properties of unfired hollow brick was studied. Results show that there is no obvious change in the initial moisture content after the use of soil stabilizer. Lime can immediately reduce the moisture content of shield muck by about 7%, the highest uniaxial compressive strength of the unfired hollow brick mixed with stabilizer and lime can increase by 27% and 7% respectively. The performance of the unfired hollow brick improves significantly with the increase of the molding pressure, and increasing water glass content can improve the uniaxial compressive strength of unfired hollow brick, whereas reduce its water resistance in a certain range. Lime as an activator is beneficial to the performance of the unfired hollow brick, whereas excessive lime has a negative effect on the strength and water resistance. It is proposed that the molding pressure is 120 kN, the addition of sodium silicate is 10%-11% and the addition of lime is 5%-9% as the best quality conditions, and the indexes of the prepared unfired hollow brick using shield muck in muddy silty clay stratum meet the specification requirements.