麦秸秆的物理力学性能及加筋盐渍土的抗压强度

Physical and mechanical properties of wheat straw and unconfined compressive strength of reinforced inshore saline soil with wheat straw

为研究滨海盐渍土的工程处理新方法,开展了防腐前后的麦秸秆吸水率、抗拉性能和加筋土的无侧限抗压强度试验。在SH胶中浸泡后的麦秸秆吸水率较天然麦秸秆明显降低,SH胶增强了麦秸秆的防腐能力;浸胶干燥后麦秸秆与天然麦秸秆相比、浸胶干燥后再浸水麦秸秆与天然浸水麦秸秆相比,前者的极限拉力和极限延伸率都高于后者,浸胶使麦秸秆的抗拉性能提高。考虑掺加不同加筋长度、不同加筋率、浸胶后呈干燥和湿润状态、不同形状的麦秸秆,测试了加筋滨海盐渍土的无侧限抗压强度。试验证实,石灰+麦秸秆加筋滨海盐渍土的抗压强度较石灰土有较大提高;加筋率0.25%和加筋长度10mm时的麦秸秆加筋土(试样直径50mm)的抗压强度最大;浸胶后呈湿润状态麦秸秆加筋土的抗压强度均高于浸胶后呈干燥状态麦秸秆加筋土的;掺加四等分的片状麦秸秆能更有效地增强加筋土的抗压强度。麦秸秆加筋不仅提高了土体的整体性和抗压强度,还限制了土体的横向变形。

The water absorption and tensile properties of original wheat straw and wheat straw marinated in SH agent are studied for developing new treatment method of inshore saline soil, and the unconfined compressive strength of reinforced saline soil with wheat straw is tested. It is shown that water absorption of wheat straw marinated in SH agent is less than that of original wheat straw, i. e. , SH agent can improve the anticorrosion of wheat straw. In drying or soaking water condition, the maximum pull and elongation of wheat straw marinated in SH agent are higher than those of original wheat straw, indicating that SH agent can enhance tensile properties of wheat straw. Considering the length, addition ratio, moisture, and shape of wheat straws marinated in SH agent, unconfined compressive tests are carried out. The results show that the strength of reinforced inshore saline soil with wheat straw and lime is higher than that of soil with lime only. The strength of the reinforced soil is maximal when the addition ratio is 0.25% and the reinforced length is 10mm （ specimen diameter 50mm）. The strength of reinforced soil with wheat straw marinated in SH agent in moist condition is higher than that in dry condition, and the strength can be effectively increased by adding four equal quarters of wheat straw. The integTality and strength of reinforced soil can be enhanced by adding wheat straw, while the deformation can be restrained.