棕榈和麦秸秆加筋上海粘土的无侧限抗压强度研究

为改良上海粘土的强度和变形特性，分别采用棕榈和麦秸秆加筋上海粘土，以提高土的强度和抗变形性能。试验以质量加筋率和加筋长度作为影响因素，分析比较两种加筋土的无侧限抗压强度。试验结果为：①棕榈加筋土的无侧限抗压强度高于麦秸秆加筋土，两种加筋土均高于素土。②棕榈的适宜加筋条件为：质量加筋率1．0％，加筋长度的平均值15mm；四分之一圆管状麦秸秆的适宜加筋条件为：质量加筋率0．3％～O．4％，加筋长度15mlTl。③棕榈加筋土的应力应变曲线表现为应变强化型，麦秸秆加筋土的应力应变曲线表现为应变软化型。试验结果表明，棕榈与麦秸秆均适宜作上海地区粘土的加筋材料，并且棕榈加筋效果优于麦秸秆。

Unconfined Compressive Strength of Shanghai Cohesive Soils Reinforced with Palm and Wheat Straws

In order to improve the strength-deformation characteristics of Shanghai soft cohesive soils, the palm and wheat straws are added in the target soil samples, respectively. The unconfined compressive strength of the soils reinforced with palm or with wheat straw is analyzed by selecting different reinforcement lengths and reinforcement ratios as influence factors. The results show that： 1） Unconfined compressive strength of the palm reinforced soils is higher than that of the wheat straw rein forced soils. Both of the reinforced soils have the higher strength than the original soil samples. 2） The optimum reinforcement length of the palm straw is approximately 15 mm and the optimum reinforcement ratio is about 1：0 % in weight： The optimum reinforcement length of tubercular wheat straw is approximately 15 mm and the optimum reinforcement ratio is about 0.3%- 0.4% in weight. 3） The stress-strain curves of the palm reinforced soils tend to be： strain-hardening type. The stressstrain curve of the wheat straw reinforced soils appear to be strain-softening type. The preliminary results show that the palm and wheat straws are both suitable for being used as reinforcement materials. The reinforcement effect of palm straws has a better result comparing with soils reinforced by the wheat straws.