Experimental Study On Engineering Performance Of Lime Soil With Different Proportions

The lime soil cushion is an economical and effective foundation treatment method in the loess area.The lime soil can not only eliminate the collapsibility of the loess layer,but also reduce the compressibility of the foundation and reduce the water permeability of the foundation,thereby improving the bearing capacity of the foundation and reducing the foundation.Settlement deformation to meet the purpose of stable and safe use of buildings.Through laboratory tests,it is concluded that there are some differences in the performance of lime soil with different gray ratios,and the change of engineering performance has a great relationship with the curing time.The performance of the three types of gray ratio(1:9,2:8,3:7)with the extension of the curing time is as follows:1)In general,the unconfined compressive strength of different gray-to-ash soils increases with the prolongation of curing time,and the rate of such strength increase is also different when the curing period is shorter and longer;within one month of the curing period The unconfined compressive strength of 1:9 lime soil increases rapidly,exceeding 2:8 lime soil and 3:7 lime soil.With the extension of curing time,its growth rate decreases rapidly;the unconfined compression resistance at one month of curing The intensity value is nearly twice that of the one-week maintenance period;in the two months of the curing period,the unconfined compressive strength of the 2:8 and 3:7 lime soils increases rapidly,and the growth rate of the later 3:7 lime soil is greater than the 2:8 lime soil.2)The lime-soil ratio of the three gray ratios increases with the curing time,and the compressive modulus is also different in the low pressure stage(maximum 0.4MPa)and the high pressure stage(3.2MPa).The compressive modulus calculated at the high pressure stage is generally greater than the compressive modulus at the low pressure stage.3)Three kinds of gray ratios of lime soil with the same compaction coefficient,the collapsibility of the treated loess is equivalent.4)With the prolonging of the curing time of lime soil,the shear strength increases,the shear failure form gradually changes from plastic to brittle,and the cohesive force and internal friction angle of the lime soil gradually increase,and the growth rate is faster in the early stage.Basically unchanged.5)Under dry curing conditions,the permeability of the lime soil will deteriorate with the extension of the curing time,and the sensitivity to water will decrease.In general,the sensitivity of 2:8 lime soil to water is small.The softening coefficient of 1:9 and 2:8 lime soil is small when the curing time is short,the water stability is poor,and the water stability gradually forms with the curing time.6)The growth of lime soil strength can be divided into two stages.In the early stage,the ionization reaction in the lime soil and the ion exchange-water gel linkage play a leading role.At this stage,the strength of the lime soil increases rapidly,and the consolidation reaction in the later stage is Leading,the increase of the strength of the lime soil increased by the consolidation reaction is slow,but the increased strength of this reaction has long-term stability,is not easily damaged by external forces,and is relatively stable to water.