Cemented stabilized rammed earth (CSRE) is a building material used to build load bearing walls from locally available soil. The article analyzes the influence of soil mineral composition on CSRE compressive strength. Compression tests of CSRE samples of various mineral compositions, but the same particle size distribution, water content, and cement content were conducted. Based on the compression strength results and analyzed SEM images, it was observed that even small changes in the mineral composition significantly affected the CSRE compressive strength. From the comparison of CSRE compressive strength result sets, one can draw general qualitative conclusions that montmorillonite lowered the compressive strength the most; beidellite also lowered it, but to a lesser extent. Kaolinite lightly increased the compressive strength.

The paper presents a study on the shrinkage properties of three clay soils from Poland. Shrinkage limit, volumetric shrinkage and relative volumetric shrinkage were determined, tested according to PN-88/B-04481 (1988) and BS1377: Part 2 (1990) and correlated with the index properties of soils. The shrinkage limit was also calculated from Krabbe's (1958) equation. The results showed that shrinkage limit values obtained by the BS method are lower than those obtained using the PN method, but the values calculated from Krabbe's equation differ significantly. While no strong correlation was found between shrinkage limit and index soil parameters, linear relationships were obtained between volumetric shrinkage and initial moisture content, shrinkage range, plasticity index and clay content. Following multivariable regression analysis, the relative volumetric shrinkage was expressed as a function of plasticity index and moisture content. This function can be used to predict volumetric changes of the foundations based on the moisture content and material properties of the soil.

This pa per pres ents the char ac ter is tics of the expansivity and quan ti ta tive pre dic tion of heave of clay soils from Po land based on suc tion test ing. Eleven Neo gene clays and six gla cial tills, dif fer ing in gen e sis and plas tic ity, were ana lysed to identify the ex pan sive po ten tial us ing eight em pir i cal meth ods. The lab o ra tory stud ies in cluded mea sure ments of soil-wa ter charac ter is tic curves and soil in dex prop er ties. Data from wa ter con tent, vol ume and suc tion mea sure ments served to de ter mine the suc tion com pres sion in dex C h and the suc tion-wa ter con tent in dex Dh/Dw of the soils ex am ined. The val ues of these in dices are clearly de pend ent on the clay frac tion con tent in tested soils. Com pared with gla cial tills, Neo gene clays are expected to ex hibit greater changes in vol ume due to changes in soil suc tion. Com par a tive re sults of the eval u a tion of expansivity sug gest that the cho sen clas si fi ca tion meth od ol o gies pro vided con sis tent ex pan sion rat ings for gla cial tills, while the val ues for Neo gene clays vary from low to very high. The low est expansivity classes have been ob tained from eval u a tion based on soil suc tion. The McKeen (1992) method has been adopted for cal cu la tions of the po ten tial field heave of Neo gene clays and gla cial tills. In or der to pro vide a ra tio nal es ti ma tion of ex pan sive soil be hav iour, spe cial ists should take into con sider ation the spe cific site and de sign fea tures.

The performed investigations were focused on analysing the variability of geological-engineering properties in clay soils from central-eastern Europe with regard to microstructures. Thirty-nine soils differing in origin, lithology and microstructure type were selected for analysis. Results of studies on lithological and physical and mechanical parameters were analysed, coupled with quantitative microstructural parameters based on microstructure images. The relationships between lithological, physical and mechanical and pore space parameters were determined with regard to microstructure types. Sediment origin and diagenesis, and soil microstructure and pore space parameters had influence on the geological-engineering properties. Such approach allows for predicting engineering parameters based on soil microstructure types and their pore space parameters.

The pa per pres ents the re sults of swell in dex, swell ing pres sure and soil suc tion tests car ried out on Neo gene clays from War saw, de pend ing on the wa ter con tent, clay frac tion, liq uid limit, plas tic ity in dex, cat ion ex change ca pac ity, and con tent of clay min er als and beidellite. These clays are con sid ered ex pan sive soils in Po land, as they are vul ner a ble to wa ter con tent vari a tions in the ac tive zone, which re sult in their vol ume change and, in con se quence, cause dam age of foun da tions and other con struc tion el e ments. A num ber of phys i cal, chem i cal and min eral prop er ties were de ter mined for these clays. The swell ing tests were car ried out on sam ples precompacted in Proc tor ap pa ra tus, at var i ous ini tial val ues of wa ter con tent. The anal y ses have shown ex po nen tial re la tion of swell in dex, swell ing pres sure and suc tion ver sus wa ter con tent. In ad di tion, the in ves ti gated re la tion ship be tween the suc tion and swell char ac ter is tics of tested clays shows good cor re la tion as a power func tion be tween these pa ram e ters. In ad di tion, va lid ity of cor re la tions be tween fit ting pa ram e ters of ob tained re la tion ships and soil in dex prop er ties, such as clay frac tion, liq uid limit, plas tic ity in dex, cat ion ex change ca pac ity, and con tent of clay min er als and beidellite, have been dem on strated. The em pir i cal re la tions are char ac ter ized by high val ues of the cor re la tion co ef fi cient. A very high fit has also been found for a pro posed re la tion ship be tween the swell in dex and swell ing pres sure for tested clays.