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Investigations of soil shear strength properties for Baltic Sea shore sand along Klaipėda city are presented. Investigated sand angle of internal friction (φ) and cohesion (c) is determined via two different direct shear tests procedures. First procedure is standard and ordinary in geotechnical practice, when direct shear test is provided using constant shearing area A0. Second test procedure is different because shearing area according to horizontal displacement each test second is recalculated. This recalculated shearing area author’s call corrected shearing area A. Obtained normal and tangential stresses’ difference via two different testing procedures was 10%. Šiame straipsnyje yra pristatyta idėja, kaip įvertinti grunto kerpamojo stiprumo parametrus, t. y. vidinės trinties kampą (φ) ir sankibą (c). Eksperimentiniams bandymams atlikti buvo naudotas Baltijos jūros pakrantės smėlinis gruntas ties Klaipėda. Grunto tiesioginio kirpimo bandymai atlikti dviem skirtingomis kirpimo metodikomis. Pirmoji metodika yra standartizuota ir įprasta atliekant geotechninius tyrimus, kai kerpamasis plotas yra vertinamas kaip pastovus plotas A. Antroji kirpimo metodika skiriasi nuo pirmosios grunto kirpimo ploto įvertinimu. Antrojoje metodikoje grunto kerpamasis plotas yra perskaičiuojamas tiesiogiai pagal horizontalųjį poslinkį. Horizontaliojo poslinkio indikatoriaus rodmenys yra registruojami kiekvieną sekundę, todėl kas sekundę yra perskaičiuojamas vis naujas grunto kerpamasis plotas. Atliekant bandymus skirtingomis metodikomis, nustatytas vertikalaus normalinio ir tangentinio įtempių skirtumas, kuris apytiksliai lygus 10 %.

Rock shear strength parameters are the basis for rock mechanics research and rock engineering applications, generally obtained by triaxial test and compression shear test method. In the current compression-shear test method, the initial shear area of the specimen is used for calculation, and the change of the shear area during the shearing process is not considered. In the actual shearing process, as the shear displacement increases, the shearing area decreases, and the compression-shearing mold has support for the shearing part of the specimen, causing the calculation error of shear stress and normal stress, so that the cohesive force error obtained by the compression shear test and the triaxial test is large. The area correction coefficient β and the support force σ mj of the shearing mold for the sheared specimen were introduced, and the shear stress and normal stress on the shear surface were corrected under the conditions of rock compression shear test. According to the Mohr–Coulomb criterion, the cohesion force is obtained, and the correction formula of rock cohesion is proposed. Verification and error analysis of the proposed formula through experiments, the correction value is closer to the true value of rock cohesion and improves the reliability of the compression-shear test method. Based on the formula of the cohesion correction formula, the influence of the test factors such as the size of the specimen was discussed. It was found that the increase of the size of the specimen helps to weaken the influence of the change of the shear area on the stress.

The goodness-of-fit analysis performed over the results provided by a model presented in a previous paper proved that the theoretical data were very well correlated with the experimental data with regard to the traction force (with Pearson coefficient r2 over 0.9); however, the model was less accurate in predicting traction efficiency, with r2 = 0.203. In order improve the model and obtain a better fit between the theoretical and experimental data (especially for the traction efficiency), the model was updated and modified by taking into account the geometry of the tire cross section, which was considered to be a deformable ellipse. Due to the deformable cross section, the minor axis of the tire–ground contact super ellipse decreased compared with the previous model (from 0.367 m to 0.222 m), while the major axis increased (from 0.530 m to 0.534 m). As a result, different data for the traction force and traction efficiency were obtained. The effect of the wheel travel reduction (wheel slip) over the tire–soil shear area was also investigated, and the hypothesis of a constant shear area (independent of wheel slip) provided the most accurate results. The goodness-of-fit analysis performed using the data predicted by the modified model showed that the Pearson coefficient increased significantly with regard to the traction efficiency (from 0.203 to 0.838), while it decreased by only 2.7% with regard to the data for the traction force, still preserving a high value (r2 = 0.896).

Seven full-scale L- and T-columns were tested using lateral cyclic loading in this research to investigate their shear and flexural behavior Based on the test observations, a new way of calculating the effective shear area that includes the contribution of the overhanging flange was proposed for L- and T-columns. The proposed effective shear area combined with the shear strength equations for columns of the ACI Code not only produced shear strengths that were more reasonably conservative but also showed less scatter than the current ACI Code method. The L- and T-columns that were designed with a sufficient amount of shear reinforcement determined by the proposed shear strength equations showed flexural, ductile behavior with ductility capacities ranging from 6.1 to 7.6. Based on the test results of these flexural columns, it was found that the ACI 318 code was conservative for the nominal flexural strength but unconservative for the maximum probable moment strength.

This paper aims to study the relationship between the microstructure and the mechanical properties of X70 submarine pipeline steel with 40.5 mm thickness. The microstructure was examined by using optical microscopy, scanning electron microscopy and an electron backscattered diffractometer, while the mechanical properties were examined by using a hardness test, a tensile test, a Charpy impact test and a drop weight tear test (DWTT), respectively. The results show that the base metal (BM) of the pipe has a low yield ratio of 0.83 and an excellent elongation of more than 45%. The DWTT shear area of the steel plate reaches 87%, showing excellent low-temperature toughness. The Charpy impact energy increases when the distance from the fusion line increases, and it reaches a maximum at the BM near the heat-affected zone (HAZ) due to the small martensite-austenite (MA) constituents and fine grains. The concentrated distribution of blocky/slender MA constituents along the prior austenite grain boundaries of the intercritically reheated coarse-grained HAZ and the large MA constituents are the main reasons for the deteriorating impact toughness. Delamination cracks in the DWTT fracture surface only occurred in the midthickness of a sample with a small opening width that spread about 2.1 mm perpendicular to the DWTT fracture surface and were finally arrested at the acicular ferrite clusters containing a high density of high-angle boundaries.

The paper deals with consideration of specimens shear area changes during direct shear test of soil and its effects on a size of spread foundation. To illustrate mentioned effects, direct shear test of soil CE will be introduced. The soil CE is a nature soil from Niepolomice, Poland and had following properties: w = 61.0%; W sub( L) = 127.9% and W sub( P) = 45%. The size of specimens was 60mm x 60mm x 15mm, time of consolidation was 4 hours and shear speeds were 0.01mm/min (slow test) and 1mm/min (quick test). The specimens had been loaded by normal stresses 50kPa, 100kPa, 200kPa, 300kPa and 400kPa. The different values of shear strength parameters, obtained by taking into account specimens shear area changes during the test and different shear speed, had been used to design spread foundation by design approaches mentioned in Eurocode 7, Part 1 (DA1-C1; DA1-C2; DA2 and DA3) and also by the old and new Slovak Technical Standard STN 73 1001. The model example for the comparison of spread foundation design by various design approaches is the model introduced by Orr (2005). It will be shown that taking into account specimens shear area changes during the test reduced foundation area from 8.0% up to 9.7% (slow test) and from 8.2% up to 8.7% (quick test) which is not negligible.

The authors of this article describe the suitability of using light dynamic penetration in the target area. The area of this survey was selected on the already reclaimed area, which, however, proved to be unstable. The main objective was to locate individual water-saturated horizons in the locality and, eventually, to determine the shear areas on which instability occurs. For this reason, several geodetically measured points were selected for dynamic penetration measurement. By this method, the water-saturated horizons are characterized by a significant reduction in dynamic resistance. Conversely, when locating the potential shear surfaces, the dynamic resistance between the saturated and unsaturated layers of the penetrated area increases sharply. After each dynamic penetration, this measurement was completed was completed with the height of the groundwater level for each point immediately after the set of rods was taken out. The resulting values were compiled by the authors in the chart for each point, and they are stated in this article as well as the evaluation of the usability of light dynamic penetration for such unstable territory.

Endothelial dysfunction is a key feature of preeclampsia and may contribute to increased cardiovascular disease risk years after pregnancy. Flow-mediated dilation (FMD) is a non-invasive endothelial function test that predicts cardiovascular event risk. New protocols allow researchers to measure three components of the FMD response: FMD, low flow-mediated constriction, and shear stimulus. This review encourages researchers to think beyond “low FMD” by examining how these three components may provide additional insights into the mechanisms and location of vascular dysfunction. The review then examines what FMD studies reveal about vascular dysfunction in preeclampsia while highlighting opportunities to gain greater mechanistic insight from new protocols. Studies using traditional protocols show that FMD is low in mid-pregnancy prior to preeclampsia, at diagnosis, and for 3 years post-partum. However, FMD returns to normal by 10 years post-partum. Studies using new protocols are needed to gain more mechanistic insight.

The quasi-in situ electron backscatter diffraction method was used to investigate the microstructure and orientation evolution of Cu-45 at.% Ni alloy during the recovery process. For the first time, the “triple junction” movement theory was verified in a Cu-Ni alloy instead of in the pure metal. The “Y-junction” movement was found to be the dominant recovery mechanism in the common lamellar grains. However, this theory did not apply to grains in the area deformed by shear. Unlike the microstructure evolution, the orientation evolution was the same in the areas not deformed and deformed by shear. All the Goss orientations were swallowed by other orientations, whereas all the cube orientations swallowed other orientations. This study helped better understand the recovery process in Cu-Ni and other face-centered cubic alloys after rolling and annealing processes.

In seismically active regions of the Earth, to which the Kamchatka peninsula refers, pre-seismic anomalies are recorded in different geophysical fields. One of such fields is the acoustic emission of rocks, the anomalies of which are recorded 1–3 days before earthquakes at the distance of the first hundreds of kilometers from their epicenters. Results of joint acoustic-deformation measurements showed that growth of geoacoustic radiation intensity occurs during the increase in the level of deformations in rock masses by more than one order compared to the background values. Simulation studies of the areas with increased deformation are realized to understand the causes of anomalous acoustic-deformation disturbance occurrences before strong earthquakes. The model is based on the assumption that the Earth’s crust in the first approximation can be considered as a homogeneous isotropic elastic half-space, and an earthquake source can be considered as a displacements along a rectangular fault plane. Based on these assumptions, deformation regions of Earth’s crust were modeled during the preparations of two earthquakes with local magnitudes ML≈5 occurred on the Kamchatka Peninsula in 2007 and 2009. The simulation results were compared for the first time with the data of a laser strainmeter-interferometer installed at the Karymshina observation site (52.83∘ N, 158.13∘ E). It was shown that, during the preparation of the both earthquakes, the Karymshina observation site was within the region of shear deformations ≈10−7, which exceeded the tidal ones by an order. On the whole, simulation results corresponded to the results of the natural observations. Construction of an adequate model for the generation of acoustic-deformation disturbances before strong earthquakes is topical for the development of an early notification system on the threat of catastrophic natural events.