scholarly journals THE STRENGTH AND DEFORMATION PROPERTIES OF COARSE-GRAINED MATERIALS FROM CYCLIC AND MONOTONIC LOADING TRIAXIAL COMPRESSION TESTS UNDER VARIOUS CONDITIONS

2008 ◽  
Vol 64 (2) ◽  
pp. 209-225
Author(s):  
Tomoko SASAKI ◽  
Tetsuo SHIMAMINE ◽  
Shinichirou NOZAWA ◽  
Masaru KIMURA ◽  
Hiroo HASEGAWA ◽  
...  
2021 ◽  
Vol 264 ◽  
pp. 02015
Author(s):  
Chorikul Raupov ◽  
Ulugbek Shermuxamedov ◽  
Anora Karimova

The paper presents the results of experimental studies on the strength and deformations of lightweight concrete, mortar matrix and hardened cement paste under triaxial compression. Tests on samples were carried out using short-term triaxial proportional σ1 > σ2 = σ3 loading (i.e. axial compression + lateral hydrostatic pressure). During the loading, the ratio of the main stresses (both axial and lateral) was kept constant up to the end of tests. The experimental studies were carried out for different low ratios of σ2/σ1. A theoretical estimation has been discussed to approximate experimental results and prediction of triaxial strength values for different types of lightweight concrete. An estimation of the confining pressure parameter K has been done for the used mode of loading.


2012 ◽  
Vol 594-597 ◽  
pp. 1159-1162
Author(s):  
Sheng Zhong ◽  
Yong Jie Yang ◽  
Min Wang

Conventional triaxial compression tests of coal specimens are carried out by MTS815 servo-controlled rock mechanical test system, and the strength and deformation characteristics of coal under different confining pressure are analyzed. On that basis, bolt supporting mechanism of surrounding rocks of roadways driving along next goaf is studied.


2021 ◽  
Author(s):  
Meisam Goudarzy ◽  
Debdeep Sarkar ◽  
Wolfgang Lieske ◽  
Torsten Wichtmann

AbstractThe paper presents an experimental study on the effect of plastic fines content on the undrained behavior and liquefaction susceptibility of sand–fines mixtures under monotonic loading. The results of undrained monotonic triaxial compression tests conducted on mixtures of Hostun sand with varying amount (0–20%) and type (kaolin and calcigel bentonite) of plastic fines are presented. The specimens were prepared with different initial densities using the moist tamping method and consolidated at two different isotropic effective stresses. The results demonstrate that for both types of plastic fines, an increase in the fines content leads to a more contractive response and lower values of mobilized deviatoric stress. Despite similar relative density and fines content, the sand–kaolin mixtures showed a more contractive behavior than the sand–calcigel specimens. The steady-state lines (SSLs) in e–p´ space generally move downwards with increasing clay content. While the slopes of the SSLs for the clean Hostun sand and the mixtures with 10 and 20% kaolin are quite similar, the SSL lines for the specimens containing 10% or 20% calcigel run steeper or flatter, respectively. The inclination of the SSL in the q–p′ plane was found independent of clay type and content. The sand–kaolin mixtures were observed to be more susceptible to instability and flow liquefaction than the sand–calcigel mixtures.


2017 ◽  
Vol 2017 ◽  
pp. 1-14
Author(s):  
Xinwei Li ◽  
Sui Zhang ◽  
E-chuan Yan ◽  
Duoyou Shu ◽  
Yangbing Cao ◽  
...  

This study focuses on mercury slag in the Tongren area of Guizhou Province, China. Computed tomography (CT) is used with uniaxial and triaxial compression tests to examine the mechanical changes in cemented mercury slag and its formation. The CT results for the uniaxial compression test reveal the overall failure process of the mercury slag structure. Based on the coarse-grained soil triaxial test, a modified Duncan-Chang model is compared with the actual monitoring results and is found to be suitable for the analysis of the slag constitutive model.


2021 ◽  
Vol 23 (4) ◽  
Author(s):  
Sheikh Sharif Ahmed ◽  
Alejandro Martinez

AbstractDifferent particle properties, such as shape, size, surface roughness, and constituent material stiffness, affect the mechanical behavior of coarse-grained soils. Systematic investigation of the individual effects of these properties requires careful control over other properties, which is a pervasive challenge in investigations with natural soils. The rapid advance of 3D printing technology provides the ability to produce analog particles with independent control over particle size and shape. This study examines the triaxial compression behavior of specimens of 3D printed sand particles and compares it to that of natural sand specimens. Drained and undrained isotropically-consolidated triaxial compression tests were performed on specimens composed of angular and rounded 3D printed and natural sands. The test results indicate that the 3D printed sands exhibit stress-dilatancy behavior that follows well-established flow rules, the angular 3D printed sand mobilizes greater critical state friction angle than that of rounded 3D printed sand, and analogous drained and undrained stress paths can be followed by 3D printed and natural sands with similar initial void ratios if the cell pressure is scaled. The results suggest that some of the fundamental behaviors of soils can be captured with 3D printed soils, and that the interpretation of their mechanical response can be captured with the critical state soil mechanics framework. However, important differences in response arise from the 3D printing process and the smaller stiffness of the printed polymeric material. Graphic abstract Artificial sand analogs were 3D printed from X-ray CT scans of sub-rounded and sub-angular natural sands. Triaxial compression tests were performed to characterize the strength and dilatancy behavior as well as critical staste parameters of the 3D printed sands and to compare it to that exhibited by the natural sands.


2015 ◽  
Vol 771 ◽  
pp. 104-107
Author(s):  
Riska Ekawita ◽  
Hasbullah Nawir ◽  
Suprijadi ◽  
Khairurrijal

An unconsolidated undrained (UU) test is one type of triaxial compression tests based on the nature of loading and drainage conditions. In order to imitate the UU triaxial compression tests, a UU triaxial emulator with a graphical user interface (GUI) was developed. It has 5 deformation sensors (4 radial deformations and one vertical deformation) and one axial pressure sensor. In addition, other inputs of the emulator are the cell pressure, the height of sample, and the diameter of sample, which are provided by the user. The emulator also facilitates the analysis and storage of measurement data. Deformation data fed to the emulator were obtained from real measurements [H. Nawir, Viscous effects on yielding characteristics of sand in triaxial compression, Dissertation, Civil Eng. Dept., The University of Tokyo, 2002]. Using the measurement data, the stress vs radial strain, stress vs vertical strain, and Mohr-Coulomb circle curves were obtained and displayed by the emulator.


2020 ◽  
Vol 57 (3) ◽  
pp. 448-452 ◽  
Author(s):  
A.S. Lees ◽  
J. Clausen

Conventional methods of characterizing the mechanical properties of soil and geogrid separately are not suited to multi-axial stabilizing geogrid that depends critically on the interaction between soil particles and geogrid. This has been overcome by testing the soil and geogrid product together as one composite material in large specimen triaxial compression tests and fitting a nonlinear failure envelope to the peak failure states. As such, the performance of stabilizing, multi-axial geogrid can be characterized in a measurable way. The failure envelope was adopted in a linear elastic – perfectly plastic constitutive model and implemented into finite element analysis, incorporating a linear variation of enhanced strength with distance from the geogrid plane. This was shown to produce reasonably accurate simulations of triaxial compression tests of both stabilized and nonstabilized specimens at all the confining stresses tested with one set of input parameters for the failure envelope and its variation with distance from the geogrid plane.


Sign in / Sign up

Export Citation Format

Share Document