Test Method for Determination of the Impact Value (IV) of a Soil

2002 ◽  
Author(s):  
Keyword(s):  
2019 ◽  
Vol 85 (7) ◽  
pp. 41-49
Author(s):  
Yaroslava V. Sulimina ◽  
Nikolay O. Yakovlev ◽  
Vladimir S. Erasov ◽  
Aleksey Yu. Ampilogov ◽  
Andrey N. Polyakov ◽  
...  

The special features of various bearing deformation measurements for pin-type bearing tests of metallic materials are considered along with their impact on the magnitude of the «bearing elastic modulus» and bearing stress. These bearing test methods are present in ASTM and various institutional standards, though no state standard (GOST, GOST R) is currently available for bearing test method of metallic materials. Analysis of additional deformations which arise in determining the degree of hole bearing deformation is carried out. A set of sources of additional deformations is shown to be characteristic for each test procedure and is attributed to the design features of the device, the site and a way of mounting the extensometer. Additional deformations can be both tensile and compressive. It is shown that the impact of additional deformations on the «bearing elastic modulus» is limited to 14% for different procedures. No difference between the methods is revealed with regard to determination of the strength characteristics. At the same time the dispersion decreases with increase in plastic deformation and for bearing deformation about 4% the variation coefficient for all methods is no more than 1%. Advantages and shortcomings of the bearing test methods which affect the reproducibility of the results are considered. The effect of the specimen geometry on the bearing characteristics is considered. It is shown that increase both in the distance from the edge of the bearing specimen to the center of the hole for 1163T, VT6ch, 30KhGSA alloys and residual bearing deformation up to 6%, increase bearing strength characteristics.


Tribologia ◽  
2018 ◽  
Vol 278 (2) ◽  
pp. 21-28
Author(s):  
Wacław GAWĘDZKI ◽  
Dariusz LEPIARCZYK ◽  
Jerzy TARNOWSKI

Buried pipelines are subjected to the action of static forces and moments caused by friction forces at the pipeline-ground contact. At the same time, pipelines are subjected to dynamic actions generated by paraseismic pulses, in particular, in areas of mining and heavy traffic. The paper presents and experimentally verifies a test method of tribological pipeline-soil interaction in conditions of artificially induced soil static and dynamic actions. The applied test methodology allows the determination of friction forces at the tested pipeline section. The friction forces changes over time on the pipeline and soil surface for the varying pipeline tensioning forces were continuously recorded during the tests. Based on the Short-Time Fourier Transform (STFT) of signals, the paper presents the impact of dynamic actions on momentary values of measured friction forces. Relationships are given that allow the determination of friction forces between the pipeline and the soil, including their limit values resulting in the loss of the mutual adhesion of the pipeline and the soil.


2017 ◽  
Vol 2017 (5) ◽  
pp. 20-28
Author(s):  
Andrzej Gruchot ◽  
Eugeniusz Zawisza ◽  
Tymoteusz Zydroń ◽  
Ewa Klimek

The research presented in this paper aimed at the determination of the impact of a test method on the liquid limit of the selected cohesive soils with different content of clay fraction: loosely cohesive – clayey medium sand, moderately cohesive on the border of loosely cohesive – coarse silt and firmly cohesive – silty clay. Liquid limit was determined by the following methods: Casagrande, Vasiliev and the cone penetrometer. It was stated, that the values of the liquid limit of the tested soils determined by various methods were different, which significantly affected the assessment of their plasticity and consistency. According to the standard PKN-CEN ISO/TS 17892-2:2009, the liquid limit should be determined with the cone penetrometer, whereas the alternative is Casagrande’s method. The conducted tests showed, that in the case of cohesive soils containing up to 10–11% of clay fraction, the differences between the values of the liquid limit determined with the cone penetrometer and the Casagrande’s method were relatively small and equaled 1–2%, therefore both methods are correct. In the case of cohesive soils containing more than 20% of clay fraction, differences between the values of the liquid limit determined with the cone penetrometer and the Casagrande’s method were slightly higher than in the previous case, and equaled approximately 4%. In those cases, determination of the liquid limit can be performed both using the first or the second method, though the above-cited standard recommends the cone penetrometer method.


Crystals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 545 ◽  
Author(s):  
Zuzana Marcalikova ◽  
Radim Cajka ◽  
Vlastimil Bilek ◽  
David Bujdos ◽  
Oldrich Sucharda

Fiber-reinforced concrete has a wide application in practice, and many fields of research are devoted to it. In most cases, this is a specific problem, i.e., the determination of the mechanical properties or the test method. However, wider knowledge of the effect of fiber in concrete is unavailable or insufficient for selected test series that cannot be compared. This article deals with the processing of a comprehensive test study and the impact of two types of fibers on the quantitative and qualitative parameters of concrete. Testing was performed for fiber dosages of 0, 40, 75, and 110 kg/m3. The fibers were hooked and straight. The influence of the fibers on the mechanical properties in fiber-reinforced concrete was analyzed by functional dependence. The selected mechanical properties were compressive strength, splitting tensile strength, bending tensile strength, and fracture energy. The results also include the resulting load–displacement diagrams and summary recommendations for the structural use and design of fiber-reinforced concrete structures. The shear resistance of reinforced concrete beams with hooked fibers was also verified by tests.


Energies ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 6226
Author(s):  
Eva Koren ◽  
Miran Veselič ◽  
Goran Vižintin

In the area of the the Krško alluvial field, the Brežice hydroelectric power plant (BHPP), with its surface water reservoir, was completed in 2017. The new BHPP reservoir dam is located approximately 7 km air distance downstream of the old Krško nuclear power plant (NEK) reservoir dam. The NEK dam was built in the 1970s. The primary purpose of the NEK reservoir is to provide fresh water for cooling the NEK nuclear reactor. To assess the impact of the newly built surface water reservoir on groundwater, we performed a series of data analyses prior to its construction. One part of the analysis relating to data from the monitoring facility of the NEK showed an interesting correspondence between the water level oscillation in the NEK reservoir and the groundwater oscillation in the nearby observation well. Based on measurements taken in 2000, we sought to estimate the clogging of the Sava riverbed sediments in the area of the old NEK surface water reservoir. To determine the permeability of the riverbed sediments, we applied geometry similar to that chosen by Hantush for his pumping test method. Using Fourier analysis, we determined the dominant frequencies from the hydrograph records of the NEK surface water reservoir and from the pressure probe in the nearby observation well. Based on the determination of the dominant frequency, we used the wave equation to compare the influence of different values of the hydraulic transmissivity of the clogged part of the NEK surface water reservoir on the transfer of its water oscillations to the groundwater in the observation well. For the hydraulic values of the non-clogged part of the aquifer (T, S), we assumed the values from the pumping experiments performed in the alluvial aquifer of Krško polje. We also assumed that the aquifer is homogeneous and isotropic, as Hantush had assumed in his method for the determination of semipervious river beds. The results obtained indicated the potential for estimation of the thickness of the clogging layer which, by analogy from applied geophysics, can be called the apparent thickness. This meant that the thickness could be determined on the basis of the default conceptual model rather than on real measurements. The presented method shows the potential for using the analysis of periodic oscillations in river reservoir level and nearby piezometers, as a method of monitoring riverbed clogging, in cases where periodical oscillations in reservoir level occur and observation wells are near enough to detect the oscillations.


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