蒙皂石含量与膨胀土膨胀势指标相关关系研究

A STUDY ON THE RELATIONSHIP BETWEEN SMECTITE CONTENT AND SWELL POTENTIAL INDICES

对沿南水北调中线工程邯郸—永年、南阳、平顶山等地区及襄樊、荆门钟祥地区采集的各类地表、近地表膨胀土样品5 6件 ,运用现代XRD定量方法和有机染料吸附方法测量了粘土矿物成分和蒙皂石含量 ,同时测定了它们的液限、塑限、自由膨胀率、比表面积、粘粒、胶粒含量等指标。蒙皂石含量与各种膨胀势判别指标研究表明 ,蒙皂石含量是各种膨胀势的主要控制因素。当然 ,各种测量误差 (主要是蒙皂石含量的测量误差 )也是影响膨胀势判别的因素。Seed膨胀势较本文采用的推荐方案划分结果高 1～ 2个级次。蒙皂石含量与各参量之间呈线性、对数、指数关系 ,与粘土矿物的“诊断”吸收特性一起 。

surface and sub-surface samples of expansive soils was collected in the Handan-Yongnian area, Nanyang district, Pingdingshan area along the middle line of the Project of Diverting Water from South to North and in Xiangfan area and Zhongxiang district of Jingmeng City. Clay mineral composition and smectite content were determined by using XRD and dye absorption methods. Meanwhile,such indices as liquid limit, plastic limit, specific surface, clay particles and colloid particles, free swell ratio were quantitatively measured. Study on smectite content and the indices for discrimination swell potential indicates that smectite content is a principal factor controlling the swell potential. Of course, the measurement errors, mainly the error in smectite content, are also the second factors influencing swell potential gradation. The swell potential graded by using Seed's method is higher by 1 to 2 levers than that by using the suggested standard in the paper. The relationship between smectite content and indices is linear, logarithmic or exponential and provides a basis for expansive soil remote sensing in relation with the diagnostic absorption features of clay minerals.