Abstract:Creep characteristics of peaty soil in Kunming affect the long-term stability and structure safety. By the improved stress-controlled direct shear apparatus, a series of direct shear creep tests are carried out with the multi-stage loading method. The variation of shear stress and strain with time and the relationship between long-term and short-term strength are studied under different consolidation pressures. The results show that the peaty soil in Kunming has obvious nonlinear creep characteristics. When the shear stress is low, the direct shear creep curve of peaty soil shows decay creep. With the increase of shear stress, both decay creep and unstable equal velocity creep appear in the creep curve. When the shear stress is high, peaty soil exhibits acceleration creep phenomenon, and is destroyed quickly. The large shear strain occurs at the moment of applying horizontal shear stress, the instantaneous strain increases with the increase of shear stress, while the proportion of instantaneous strain to total strain decreases gradually, which indicates that the creep deformation is aggravated under high shear stress. Compared with short-term strength, the cohesion and friction angle of long-term strength is smaller for peaty soil, and the long-term strength is about 57%~70% of the short-term strength when the consolidation pressure is 50-400kPa.
何仕娟 王志良 瞿嘉安 申林方 丁祖德. 昆明泥炭土直剪蠕变特性及长期强度试验研究[J]. 土木工程学报, 2019, 52(S1): 16-22.
He Shijuan Wang Zhiliang Qu Jiaan Shen Linfang Ding Zude. Experimental study on direct shear creep characteristics and long-term#br#
strength of peaty soil in Kunming. 土木工程学报, 2019, 52(S1): 16-22.