中文摘要：

Xu等[1]提出基于膨润土表面分形模型的膨胀变形计算方法Vw/Vm =kPDs^-3（式1）,并得到了Tsukinuno膨润土、Wyoming膨润土和MX80膨润土的膨胀变形和膨胀压力（统称膨胀变形）的膨胀试验数据的验证.当时由于条件限制,存在两个问题（1）膨润土的表面分维一般采用氮吸附法测量,由膨胀变形试验数据反算得到的膨润土表面分维没有得到氮吸附试验数据的验证;（2）在归一化吸水体积与压力的分形模型（式1）中,K是膨润土的物性常数,没有给出理论表达式,只是经验系数.本文采用氮吸附方法测量了高庙子Na基膨润土、高庙子Ca基膨润土、商用膨润土和Tsukinuno膨润土的表面分维,根据式（1）由表面分维计算膨胀变形,并与膨胀试验数据比较,验证膨胀变形的分形模型;根据双电层理论,导出用双电层参数表示式（1）中K值的理论表达式,用于膨胀变形的计算,并与膨胀变形试验结果进行比较验证.

英文摘要：

On the base of the fractal model for bentonite surface,Xu et al.[1 ] proposed a new method to calculate the swelling deformation of bentonite and expressed as the equation Vw/Vm=KpDs-3(Eq.(1 )),which were verified by the experimental data of swelling deformation and swelling pressure of Tsukinuno bentonite,Wyoming bentonite and MX-80 bentonite.Due to the limitation of experiments,two factors to be improved are listed as follows:(1 )the fractal dimension obtained from the swelling test was not validated with results of the N2 isotherm adsorption;(2) the expression of the parameter K in Eq.(1 )was given on the basis of an empirical equation.In this paper,the surface fractal dimension of Gaomiaozi Na-bentonite and Ca-bentonite,a commercial bentonite and Tsukinuno bentonite are measured using the N2 isotherm adsorption.The swelling deformation is calculated and verified from the above equation using the surface fractal dimension of Gaomiaozi Na-bentonite and Ca-bentonite,a commercial bentonite and Tsukinuno bentonite.Expression of the parameter K in the above equation is deduced from the diffused double layer(DDL)theory.