【目的】对海淤软土地基进行轻质化处理,制备具有轻质、高强特点的海淤建筑废料混合轻质土,可以减轻疏浚海淤地基的沉降。【方法】以疏浚海淤泥为原料土、水泥为固化剂、轻质建筑废料为轻质材料,采用优选配合比设计方法,研究组成材料对混合轻质土密度和强度的影响。同时以轻质高强、经济合理为原则,提出该混合轻质土的强度配比公式,并测试其耐久性指标水稳定性。【结果】水泥用量对混合轻质土密度影响较小,而轻质建筑废料用量对混合轻质土密度影响较大,随着轻质建筑废料用量的增加,混合轻质土密度降低;水泥用量和轻质建筑废料用量对混合轻质土的无侧限抗压强度影响均较大,当轻质建筑废料用量不变时,随着水泥用量的增加,混合轻质土强度增加;而当水泥用量不变时,随着轻质建筑废料用量的增加,混合轻质土的强度先增加后降低,存在一个峰值。【结论】不同的原料土、固化剂和轻质材料配比都会对轻质土的物理、力学性质产生影响,在实际工程应用中,在参考该研究提出的配比公式时,如混合轻质土的组分发生变化,还需要对其实用性进行验证。
[ Objective ] To reduce the settlement of the foundations in dredged sea silt, light treatment was adopted, through preparing sea silt-construction waste mixed lightweight soil with the characteristics of lightweight and high- strength. [ Method] The final mixture took dredged sea silt as raw soil, cement as curing agent and light construction waste as light material. The optimum mixture ratio was determined by examining the influence of the compositions of the mixture on the density and strength of the final material. Meanwhile, taking the lightweight, high-strength, and economic requirements of the final material into consideration, the ideal ratio for mixing lightweight soil to cement and the water stability of the resulting mixture were determined. [ Results ] The cement component had very little influence on the density of the final material. The lightweight construction waste component had a more significant effect on the density of the mixture, which decreased with increasing amounts of lightweight construction waste. Both the cement and the light- weight construction waste components influenced the unconfined compression strength of the mixture. When the amount of the lightweight construction waste component was kept constant, the strength of the mixture increased with increasing a- mount of cement. Conversely, the strength of the mixture increased initially with increasing amount of the lightweight construction waste and then decreased, leading to the peak strength value. [ Conclusion] Different raw soil, curing agent and lightweight materials all affected the physical and mechanical properties of the mixture. In practical engineering ap- plications, if the composition of the mixture chan~ed, it is necessary to verify the practical applicability of this formula.