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The paper analyses problems of correlation between the results of dynamic probing (DPSH -Super heavy dynamic probing) and cone penetration test. According to investigations of geological cross-sections of cohesive soils of the territory of Lithuania correlation dependencies are evaluated. Reliability of dynamic probing and modern methods of results correction are discussed. Effect of DPSH rods and lateral stress of soils to the results of probing is evaluated. Correlation dependencies between blow count N and depth of probing and cone resistance q c for various cohesive soils found in the territory of Lithuania.

The Cathedral of Vilnius is one of the main architectural monuments in Lithuania. This structure was built in unfavourable geological conditions. Due to this reason, the foundation of the building subsides; there occur wall deformations and cracks. Preservation of the building is today’s urgent problem. When evaluating the geologic environment from the perspective of engineering, construction works require deep analysis of the following key environment components and discuss them: relief, soils of geologic structure and their geotechnical properties, conditions of underground water occurrence and geological processes, and condition of the foundation. The article provides the brief history of construction and reconstruction of the Cathedral based on archival studies, the description of engineering geological conditions, and the archeologic and historic material of the evaluation of the foundation.

The Lithuanian state road network consists of more than 21,000 km of roads, and gravel roads dominate (43.3%). While the 1998–2000 Paving of Gravel Roads Program was being implemented, there were a few issues in estimating investments that could determine the implementation alternatives of the rehabilitation project. Total costs of renovated gravel roads depended on the climate and geological and hydrological conditions of a location as well as traffic and gravel road characteristics. Roads, like engineering buildings, have to be of sufficient strength and durability, and they should correspond to traffic volume. The results of tests showed diversity of pavements and the characteristics of renovated gravel roads. Gravel roads vary by road width, pavement structure, pavement materials, and traffic. In analyzing traffic on gravel roads, the roads were classified into four groups according to traffic volume. Frequently, the strength of subgrade soils determines the structure of renovated gravel roads. The authors carried out tests on road subgrades under different geomorphologic and geological conditions, estimating the structure, physical conditions, and mechanical properties of these subgrades. According to the test results the strength of existing gravel roads depends on the strength of the subgrade, the thickness of the gravel road, and the quality of the gravel. The equivalent deformation modulus of the gravel roads is described by a binomial. In selecting structures for reconstruction of gravel roads, mathematical models are suggested.

This article presents results of the test conducted on the undrained shear strength of till clayey soils of Eastern Lithuania, which are characterized by rigid and very stiff consistency and low plasticity. According to the classification of soils presented in LST EN ISO 14688–2:2018 Geotechnical Investigation and Testing – Identification and Classification of Soil − Part 2: Principles for a Classification, the tested soils are classified as sandy low plasticity clays. The undrained shear strength was tested using the triaxial compression (unconsolidated undrained) method. The test results showed that peculiarities of the particle size distribution had a crucial impact on the undrained strength of these soils, i.e. on the correlation of clay and fine silt fractions with the rest of soil components.