Title: Experimental study on the use of compound alkaline materials to solidify lake sediments
Date Published: September - October 2023
Volume: 68
Issue: 5
Page Numbers: 42 - 56
Authors: Hongdan Yu, Kai Zhang, Haifeng Lu, and Qingzhao Zhang
https://doi.org/10.15554/pcij68.5-03
Click here to view the full article.
Abstract
The disposal of lake sediment is a major problem in dredging and lakeside construction projects. Due to its poor mechanical properties and contamination, sediment is difficult to use directly in resource applications. Previous research has found that alkali-activated reactions can improve the mechanical properties of silicon- and aluminum–rich solid waste. In this study, the basic physical and mechanical properties of dried sediment from a lake in Wuhan, China, were analyzed. Orthogonal tests, compressive strength measurements, and X-ray diffraction spectrum and scanning electron microscope analyses were used to investigate the solidification effects of three types of alkaline materials used alone or in combination with the lake sediment: straw ash, calcium lime, and sodium silicate. In the single-doped samples, calcium lime had the best curing effect, with a maximum seven-day compressive strength of 1.31 MPa (190 psi). When the compound-doped samples were cured to seven days, the maximum compressive strength was 7.18 MPa (1040 psi). Furthermore, with the compound-doped materials, sediment solidification was aided by suitably alkaline conditions and large quantities of active silicon-calcium components. As a result, the microstructures of the cured compound-doped samples were more compact and their overall mechanical properties were greatly improved.