Study on the Improvement of Waterproof Performance of Historical Silt Sites with Silicone Waterproofing Agent

Abstract

Silt has the characteristics of obvious capillary water effect and strong water sensitivity. The flooding of the Yellow River caused the water level in Kaifeng to be high, and the damage of capillary water to the silt site of Kaifeng Zhouqiao site is increasing day by day. In order to improve the waterproof performance of the site soil, three kinds of silicone waterproof materials were selected, and the site soil was improved by internal mixing. The improvement effects of different materials were compared through the capillary water rise test, and the contact angle of the modified soil with the optimal ratio was measured. Microscopic tests were conducted to evaluate its wetting properties and reveal the mechanism of action of the modified materials. The results show that the three kinds of silicone waterproofing agents can improve the waterproofing effect of soil, among which 0.5% sodium methylsilicate modified soil has the most significant waterproofing effect; its capillary water absorption inhibition effect can reach 98.34%, and the contact angle is 137.06. The surface of the modified soil is hydrophobic after the addition of sodium methylsilicate. An evenly distributed waterproof film is thus formed on the surface of the soil particles, which changes the contact mode between the soil particles and strengthens the connection between the soil particles, so that the proportion of large pores decreased. The proportion of mesopores and small pores increased, which made the soil sample more compact. These results explain the improvement of the waterproof performance of the soil sample.

Study on Composite Improvement of Silt Sites by Lignin and Sodium Methylsilicate and Its Micro Mechanism

“…Through compaction test, strength test and permeability test, it is believed that it can significantly improve the mechanical and impermeability properties of silty sand in the Yellow flood area [12][13][14]. In conclusion, sodium methylsilicate can significantly improve the cohesion and internal friction angle of soil, and play a hydrophobic role in the dry wet cycle test [15][16][17]; Lignin fiber can form an integral spatial network structure with soil particles, effectively improving the strength of soil [18].…”

Study on the corrosion resistance of composite modified anti-corrosion mortar under the action of bio-organic water

“…Adding a waterproofing agent can reduce the number of open pores in concrete, lower water absorption, and effectively improve the resistance to chloride ion diffusion (Xiang et al, 2021;Chen et al, 2022). Sodium methyl silicate in cementitious materials will form a water-repellent reticular film with low surface tension to block ion penetration, thus significantly improving the impermeability of the material (Li et al, 2022;Ma et al, 2022). Inorganic water repellents can generate insoluble colloids and swelling compound salt crystals inside the material to fill the pores and increase the material's density, improving the material's corrosion resistance.…”