ASSESSMENT OF SHEAR STRENGTH PARAMETERS OF SOIL FROM LOAD MICROPILE TESTS

Design and evaluation of the bearing capacity of micropiles are based on shear strength parameters of the soil within which a micropile is installed. These parameters are mostly received from laboratory tests or as an expert evaluation relying on soil description, classification and collected experience. This paper presents an approach that determines cohesion and angle of internal friction from diagrams of displacement on load, these being obtained by compression and traction load tests of real micropiles installed in the known soil. Furthermore, the diagrams are interpreted by the Mohr-Coulomb strength criterion and the desired values of shear strength are thus derived by using it

Results of experimental measurement of leakege of a construction joint sealed with the bentonite waterproof mattress

Příspěvek přináší výsledky experimentálních laboratorních měření propustnosti konstrukční spáry utěsněné překrytím bentonitovou hydroizolační matrací. Měření probíhalo na fyzikálním modelu krátkého úseku konstrukční spáry. Měření byla provedena pro několik variant utěsnění a situaci bez izolace. Naměřené hodnoty objemů průsaků vody jsou zpracovány do grafických závislostí, které dokumentují časový vývoj průsaku konstrukční spárou. Druhým výsledkem provedených experimentů je ověření laboratorního postupu měření průsaku konstrukční spárouThe paper reports the results of experimental laboratory leakage measurements of a construction joint sealed with the bentonite waterproof overlaying mattress. Measurements were carried out on the physical model for the short length of a construction joint. The measurements were performed for several variants of construction joint overlaying and a situation without it. The measured values of leak water volumes are processed into graphical relationships that document the time dependency of the construction joint leakage. The second result of the experiments is verification of the laboratory procedure to measure the leakage of a construction join

Experimentally measurement and analysis of stress under foundation slab

Understanding of a load redistribution into subsoil below building foundation is an important knowledge for reliable design and its economy too. The article presents the results of a physical model of a foundation slab and its interaction with the subsoil. The interactions were investigated comprehensively by monitoring the developments of stress in the subsoil and foundation slab settlement during its loading. The load acting on the foundation was applied by strutting the hydraulic press against heavy steel frame which was established by the Department of Building Structures, Faculty of Civil Engineering of VSB -TU Ostrava for this purpose. The preparatory phase of the present experiment involved the homogenization of soil during which trio pressure cells in three horizons were gradually fitted. The quality of homogenization was checked on an ongoing basis through field tests: dynamic penetration load test, dynamic plate load test and seismic measurement of foundation slab response. Finally, the homogenized soil was subjected to mechanical analysis to determine the strength and deformation parameters for basic Mohr-Coulomb constitutive model.Web of Science133513512

Základy geotechnických staveb a konstrukcí

E-vyuk