Dynamic Characteristics of Cement-Phosphogypsum Improving Peaty Soil

Abstract

Abstract: In order to study the effect of cement-phosphogypsum comprehensive improvement on the dynamic characteristics of peaty soil in Dianchi area of Kunming, the laboratory dynamic triaxial test of improved peaty soil with different content of cement and phosphogypsum was carried out based on the previous laboratory test results. The effects of dynamic response and strength characteristics under different confining pressures, loading frequencies, dosages, consolidation ratios and dynamic stress amplitudes were mainly studied. The hysteresis curve change law at N=6 vibration level and the results of XRD test were analyzed. The results show that the dynamic characteristics of improved peaty soil change greatly. On the basis of separately adding cement as the main modifier, the stiffness and elasticity have been slightly improved. After adding phosphogypsum as an admixture, the combined effect is more obvious, the deformation resistance is improved significantly, the energy dissipation ability of soil is reduced, and the hysteresis curve has an obvious tendency to deflect to the longitudinal axis, which indicates that compared to the single action of cement, the composite action of cement-phosphogypsum has a more significant improvement effect on the soil stiffness and elasticity of the improved peaty soil, greatly improving the seismic performance. The improved peaty soil can be better applied to relevant practical engineering.

Key words: peaty soil, cement-phosphogypsum, curing agent, dynamic characteristic, hysteretic curve

CLC Number:

TU411

QU Juntong, LUAN Kaiyu, PU Junxiang, WANG Wenbin, LONG Ningbo. Dynamic Characteristics of Cement-Phosphogypsum Improving Peaty Soil[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2023, 42(12): 4427-4437.

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