scholarly journals APPLICATION OF SEISMIC DILATOMETER FOR CEMENTATION ANALYSIS IN RESIDUAL GNEISS SOIL

2021 ◽  
Keyword(s):  
Small Strain ◽  
Residual Soil ◽  
Solid Skeleton ◽  
Penetration Test ◽  
Residual Soils ◽  
Cone Penetration ◽  
Different Types ◽  
Additional Resistance ◽  
Matrix Rock ◽  
And Behavior

Residual soils have different properties and behavior from sedimentary soils. Aspects related to the processes of origin and formation directly impact these geotechnical particularities. One of the characteristic properties of this material is cementation. Cementation is an additional resistance that occurs in the solid skeleton due to weathering actions on these materials. In a residual soil profile, different cementation levels occur between the grains, these differences are due to different types of matrix rock, decomposition mechanisms involved in the process and anthropic actions. This article evaluated changes in the degree of cementation in residual soil horizons using the Marchetti Seismic Dilatometer (SDMT). The research was carried out in a residual gneiss soil in the State of Santa Catarina. The evaluation of the cementation degree was based on the relationships obtained with the Go (shear modulus with small strain) and other field geotechnical indices. The results show that the interpretation of the correlations from the results obtained by the SPT (Standardized Penetration Test), CPT (Cone Penetration Test) and SDMT tests allow the identification of layer boundaries with different degrees of cementation in residual gneiss soils. . In the present work, the limits between the saprolitic and the lateritic layers were identified and, finally, it was concluded that the studied residual soil presents a low level of cementation between the particles.

Small strain stiffness for granite residual soil: effect of stress ratio

2021 ◽  
Author(s):  
Xianwei Zhang ◽  
Xinyu Liu ◽  
Lingwei Kong ◽  
Gang Wang ◽  
Cheng Chen
Keyword(s):  
Stress Ratio ◽  
Small Strain ◽  
Residual Soil ◽  
Resonant Column ◽  
Residual Soils ◽  
Column Tests ◽  
Small Strain Stiffness ◽  
Deviator Stress ◽  
Granite Residual Soil ◽  
Stress Ratios

Most previous studies have focused on the small strain stiffness of sedimentary soil while little attention has been given to residual soils with different properties. Most studies also neglected the effects of the deviator stress, which is extensively involved in civil engineering. This note considers the effects of the deviator stress on the small-strain stiffness of natural granite residual soil (GRS) as established from resonant column tests performed under various stress ratios. Although increasing the stress ratio results in a greater maximum shear modulus for both natural and remolded residual soils, remolded soil is more sensitive to changes in the stress ratio, which highlights the effects of soil cementation. The data herein offers new insights to understand the stiffness of residual soil and other weathered geomaterials.

scholarly journals Characterization of Norwegian marine clays with combined shear wave velocity and piezocone cone penetration test (CPTU) data

2010 ◽  
Vol 47 (7) ◽  
pp. 709-718 ◽  
Author(s):  
Michael Long ◽  
Shane Donohue
Keyword(s):  
Shear Wave ◽  
Wave Velocity ◽  
Shear Wave Velocity ◽  
Small Strain ◽  
Cone Penetration Test ◽  
Research Quality ◽  
Penetration Test ◽  
Cone Penetration ◽  
Tip Resistance ◽  
Marine Clays

A database of research-quality piezocone cone penetration test (CPTU) and shear wave velocity, Vs, information for Norwegian marine clays has been assembled to study the small-strain stiffness relationships for these materials and to examine the potential use of CPTU and Vs data in combination for the purposes of characterizing these soils. Data for sites where high-quality block sampling was carried out have mostly been used. Improvements have been suggested to existing correlations between the small-strain shear modulus, Gmax, or Vs and index properties for these soils. Recent research has shown that CPTU corrected cone tip resistance, qt, and especially the pore pressure measured during CPTUs, u2, and Vs can be measured reliably and repeatably and are not operator or equipment dependant. Therefore, a new soil classification chart involving the normalized cone resistance, Qt, and normalized shear wave velocity, Vs1, or Vs1 and Δu/[Formula: see text] (where u is the pore-water pressure and [Formula: see text] is the in situ vertical effective stress) is presented. Using this chart it is possible to clearly distinguish between clays of different overconsolidation ratios (OCRs).

scholarly journals COMPRESSIBLE THICKNESS DEPTH DETERMINATION UNDER DIFFERENT CALCULATION METHODS OF THE SETTLEMENTS ACCORDING TO NATIONAL AND EUROPEAN STANDARDS

2017 ◽  
Vol 2 (49) ◽  
pp. 88-98
Author(s):  
N. G. Lobacheva
Keyword(s):  
National Standards ◽  
Penetration Test ◽  
Calculation Methods ◽  
Cone Penetration ◽  
Limiting State ◽  
Regulatory Documents ◽  
Depth Determination ◽  
Different Types ◽  
Geotechnical Design ◽  
European Standards

The comparison of the compressible thickness values and the settlements values according to the cone penetration test data in accordance with the  current regulatory documents of the Belarus Republic and EUROCODE 7 «Geotechnical design» (part 1, 2) is presented. Two calculation methods of the foundation settlement  for the limiting state of SLS and two methods for calculating of the settlements according to National standards are considered according to European norms. The ratios of the compressible thickness and the upset distances are determined using different calculation methods according to European and National standards. The proportions of the compressible thickness and the settlements values for different types of foundations are determined according to European and National standards.

scholarly journals On the interpretation of seismic cone penetration test (SCPT) results

2013 ◽  
Vol 35 (4) ◽  
pp. 3-11 ◽  
Author(s):  
Irena Bagińska ◽  
Wojciech Janecki ◽  
Maciej Sobótka
Keyword(s):  
Test Performance ◽  
Ground Surface ◽  
Small Strain ◽  
Cone Penetration Test ◽  
Penetration Test ◽  
Cone Penetration ◽  
Soil Medium ◽  
Small Strain Shear Modulus ◽  
Different Depths ◽  
Seismic Cone Penetration Test

Abstract The paper deals with the methodology of performing and interpretation of seismic cone penetration test (SCPT). This type of test is used to determine velocity of the seismic wave in the soil medium. This study is focused on shear wave. The wave is triggered on the ground surface by hitting an anvil with a sledgehammer. Then, vibrations induced at different depths are measured. Based on recorded measurements wave velocity (Vs) and thus also small strain shear modulus Gmax may be calculated. An interpretation of exemplary seismic test results is presented. Crossover and cross-correlation methods are discussed and another, more adequate one is featured and then applied in the interpretation example. Conditions for correct test performance and interpretation are discussed.

scholarly journals Ground improvement using an expandable polyurethane resin

2018 ◽  
Vol 245 ◽  
pp. 01004
Author(s):  
Mohanad Sabri ◽  
Aleksandr Bugrov ◽  
Stanislav Panov ◽  
Viacheslav Davidenko
Keyword(s):  
Ground Improvement ◽  
Load Test ◽  
Penetration Test ◽  
Cone Penetration ◽  
Plate Load Test ◽  
Polyurethane Resin ◽  
Different Types ◽  
Before And After ◽  
Dynamic Cone Penetration Test ◽  
Dynamic Cone Penetration

The paper describes an experiment conducted to study the effect of injection an expandablepolyurethane resin on the stabilization, settlement reduction and increasing the bearing capacity of the foundation’s soil. The experiment was carried out in sandy soil, and different types of soil investigations were carried out to investigate the effect of the resin on the soil properties beneath a concrete foundation. Results of Plate load test PLT and dynamic cone penetration test DCPT before and after the injection of the expandable resin are demonstrated and discussed in this paper.

Changes in abdominal muscles architecture induced by different types of breathing

2021 ◽  
pp. 1-7
Author(s):  
Iria Da Cuña-Carrera ◽  
Alejandra Alonso-Calvete ◽  
Yoana González-González ◽  
Mercedes Soto-González
Keyword(s):  
Effect Size ◽  
Health Care Professionals ◽  
Rectus Abdominis ◽  
Transversus Abdominis ◽  
Abdominal Muscles ◽  
Healthy Population ◽  
Different Types ◽  
Architectural Characteristics ◽  
And Behavior ◽  
Internal Oblique

BACKGROUND: The underlying morphology and behavior of abdominal muscles during breathing are still lacking in knowledge in healthy population. OBJECTIVE: To analyze the effects of three different types of breathing on the architectural characteristics of abdominal muscles. METHODS: Ninety-eight healthy subjects were measured to assess the effects of breathing on the abdominal muscles, subjects performed three different types of breathing and the muscular thickness was measured with ultrasound imaging, analyzing also the differences between sexes. RESULTS: During the three different types of breathing and in comparison with the resting state, an increase of the thickness has been reported in the transversus abdominis (p< 0.001; effect size = 2.44, very large) and internal oblique (p< 0.001; effect size = 1.04, moderate) in both sexes, but with a higher increase in men. External oblique and rectus abdominis increased their thickness through breathing only while the lips were with pursed (p< 0.05) with trivial effect sizes and only differences between sexes were found in rectus abdominis. CONCLUSIONS: All breathings activated the deepest abdominal muscles, but the most superficial were only activated with lips pursed. Moreover, men appeared to activate more the deepest abdominal muscles but also the rectus abdominis. Findings in this study support the use of different types of breathing depending on the muscle to be activated or the sex, helping health care professionals to address their interventions on the abdominal muscles with a more focused approach.

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