The paper discusses the results of mechanical and technological tests of soil-cement composites made with cohesive soil. The compositions of analysed soil-cement mixtures differed in terms of their cement paste volume fractions and water-cement ratios. Limiting values of these technological parameters that enable the application of the soil-cement mixtures obtained in real life conditions for the purposes of the Deep Soil Mixing (DSM) method were determined. Based on the test results obtained, it was found that mechanical properties of the materials analysed were very sensitive to changes in their compositions. Variations in the volume fraction of cement paste within the range analysed caused mechanical properties to change even by an order of magnitude.

The paper deals with mechanical properties of soil-cement composites made with non-cohesive soil and reinforced with dispersed fibers. The research was carried out on the basis of three soil-cement matrices whose compositions varied in terms of the volumetric fraction of cement paste and the water-cement ratio. Two types of polypropylene fibers were used as dispersed reinforcement: single fibrillated-tapes polypropylene fibers (SFPF) and bundles of coiled fibrillated-tapes polypropylene fibers (BCFPF). The fibers varied in terms of their length and mass fraction. The objective of the study was to assess the effect of the addition of fibers to soil-cement composites on their flexural tensile strength and on their behavior in the post-critical state. The studies were carried out after 28 days of curing. Bending tests were carried out to determine post-critical stress values σ_CMODi, stress values at which the matrix is destroyed (limit of proportionality) σ_LOP, maximum stress values transferred by the fibers σ_MOR (modulus of rupture), and total fracture energy G_f,tot as well as compressive strength. The test results obtained, and their analysis, indicate the significant impact of the dispersed reinforcement used on the performance of such composites during bending.

The paper discusses results of mechanical and technological tests of soil-cement composites made with cohesive or non-cohesive soil. The compositions of the soil-cement mixtures analysed differed in terms of their cement paste volume fractions and water-cement ratios. Limiting values of these technological parameters that enable the application of the soil-cement mixtures obtained in real life conditions for the purposes of the Deep Soil Mixing (DSM) method were determined. Based on the test results obtained, it was found that mechanical properties of the materials analysed were very sensitive to changes in their compositions. Variations in the volume fraction of cement paste within the range analysed caused mechanical properties to change even by an order of magnitude.

Artykuł prezentuje krótki rys historyczny LaboratoriumBadawczego Materiałów i Konstrukcji Budowlanych, funkcjonującegow strukturze Wydziału Inżynierii Lądowej. Przedstawionezostały jego główne obszary i możliwości badawcze orazwymienione niektóre ze zrealizowanych w laboratorium projektówbadawczych. Ponadto zaprezentowano przykładowe badaniaelementów nawierzchni kolejowych oraz próbek betonu, zgrupowanew linie badawcze, które mieszczą się w zakresie akredytacjilaboratorium badawczego