【摘要】 为研究干湿循环条件下石灰土的水稳定性,对不同石灰掺量的石灰土试样进行干湿循环处理,开展无侧限抗压强度、密度和质量损失率试验,探究石灰土的强度和变形等物理力学性质。结果表明:石灰土在干湿循环作用下强度骤然降低,但随着干湿循环次数的增加强度有所提高并最终趋于稳定,长期干湿循环作用会使试样强度衰减37.58%～51.42%,但石灰掺量为15%时能有效抑制强度的衰减;石灰土在干湿循环作用下密度骤然增大16.94%～20.26%,初期表现出强烈的吸水特性,但随后密度不再增大;在干湿循环前期,石灰土试样会因土体内部火山灰作用和碳酸化作用而吸水,表现为石灰土质量先陡增后趋于稳定,反映出一定的抗水蚀性能;长期干湿循环作用下,试样破坏形态由脆性破坏转变为塑性破坏;建议在实际工程中将石灰土地基应用于干燥环境,采用15%的最优石灰掺量,即灰土体积比3∶7、含水率27.64%,以保证干湿循环对石灰土地基的水稳定性影响程度最小。更多还原

【Abstract】 In order to study the water stability of lime soil under dry-wet cycle conditions,the lime soil samples with different lime contents were subjected to dry-wet cycle treatment. The unconfined compressive strength,density and mass loss rate tests were carried out to explore the physical and mechanical properties of lime soil,such as strength and deformation. The results show that the strength of lime soil decreases suddenly under the action of dry-wet cycle,but the strength increases with the increase of dry-wet cycle times and finally tends to be stable. The long-term dry-wet cycle will reduce the strength of the sample by 37. 58% ～51. 42%. However,when the lime content is 15%,it can effectively inhibit the attenuation of strength. The density of lime soil increases by 16. 94% ～20. 26% under the action of dry-wet cycle. At the beginning,it shows strong water absorption characteristics,but then the density no longer increases. In the early stage of the dry-wet cycle,the lime soil sample will absorb water due to the pozzolanic effect and carbonation inside the soil,which shows that the quality of the lime soil first increases sharply and then tends to be stable,reflecting a certain resistance to water erosion performance. Under the action of long-term dry-wet cycle,the failure mode of the sample changes from brittle failure to plastic failure. It is suggested that the lime soil foundation should be applied to the dry environment in practical engineering,and the optimal lime content of 15% should be adopted,that is,the volume ratio of lime soil is 3 ∶7 and the water content is 27.64%,so as to ensure that the dry-wet cycle has the least influence on the water stability of lime soil foundation.更多还原