Volumetric Strain in Non-Plastic Silty Sand Subject to Multidirectional Cyclic Loading

2017 ◽  
Author(s):  
Lopamudra Bhaumik ◽  
Cassandra J. Rutherford ◽  
Alfonso Cerna-Diaz ◽  
Scott M. Olson ◽  
Ozgun A. Numanoglu ◽  
...  
Keyword(s):  
Cyclic Loading ◽  
Volumetric Strain ◽  
Silty Sand

Residual Deformation Behavior of Reinforced Rock-Fill Materials

2010 ◽  
Vol 150-151 ◽  
pp. 1495-1499
Author(s):  
Yong Liang Lin ◽  
Meng Xi Zhang ◽  
Xin Xing Li
Keyword(s):  
Cyclic Loading ◽  
Deformation Behavior ◽  
Residual Deformation ◽  
Volumetric Strain ◽  
Test Results ◽  
Rock Fill ◽  
Triaxial Apparatus ◽  
Deformation Behaviors ◽  
Confining Pressures ◽  
Fill Materials

Reinforcement technology is widely used in rock-fill dams in high seismic hazard zones. The evaluation of reinforcement on deformation and safety is concerned and it is one of the major study objectives in rock-fill engineering. The residual deformation behaviors of reinforced rock-fill materials were experimentally studies by use of a triaxial apparatus. The effects were analyzed of intervals of reinforcement layers, confining pressures and the conditions of cyclic loading on residual deformation. Results show that reinforcement improves the residual deformation behaviors of rock-fill materials. Both the residual shear strain and the residual volumetric strain are deduced. Based on the test results, the mechanism of the influence of reinforcement on residual deformation is proposed tentatively.

scholarly journals Effects of relative density and accumulated shear strain on post-liquefaction residual deformation

2013 ◽  
Vol 13 (10) ◽  
pp. 2567-2577
Author(s):  
J. Kim ◽  
M. Kazama ◽  
Y. Kwon
Keyword(s):  
Cyclic Loading ◽  
Relative Density ◽  
Shear Strain ◽  
Axial Strain ◽  
Residual Deformation ◽  
Volumetric Strain ◽  
Monotonic Loading ◽  
Test Method ◽  
Lateral Strain ◽  
Undrained Conditions

Abstract. The damage caused by liquefaction, which occurs following an earthquake, is usually because of settlement and lateral spreading. Generally, the evaluation of liquefaction has been centered on settlement, that is, residual volumetric strain. However, in actual soil, residual shear and residual volumetric deformations occur simultaneously after an earthquake. Therefore, the simultaneous evaluation of the two phenomena and the clarification of their relationship are likely to evaluate post-liquefaction soil behaviors more accurately. Hence, a quantitative evaluation of post-liquefaction damage will also be possible. In this study, the effects of relative density and accumulated shear strain on post-liquefaction residual deformations were reviewed through a series of lateral constrained-control hollow cylindrical torsion tests under undrained conditions. In order to identify the relationship between residual shear and residual volumetric strains, this study proposed a new test method that integrates monotonic loading after cyclic loading, and K0-drain after cyclic loading – in other words, the combination of cyclic loading, monotonic loading, and the K0 drain. In addition, a control that maintained the lateral constrained condition across all the processes of consolidation, cyclic loading, monotonic loading, and drainage was used to reproduce the anisotropy of in situ ground. This lateral constrain control was performed by controlling the axial strain, based on the assumption that under undrained conditions, axial and lateral strains occur simultaneously, and unless axial strain occurs, lateral strain does not occur. The test results confirmed that the recovery of effective stresses, which occur during monotonic loading and drainage after cyclic loading, respectively, result from mutually different structural restoration characteristics. In addition, in the ranges of 40–60% relative density and 50–100% accumulated shear strain, relative density was found to have greater effects than the number of cycles (accumulated shear strain).

Cyclic strength of a natural liquefiable sand stabilized with colloidal silica grout

2008 ◽  
Vol 45 (10) ◽  
pp. 1345-1355 ◽  
Author(s):  
J. A. Díaz-Rodríguez ◽  
V. M. Antonio-Izarraras ◽  
P. Bandini ◽  
J. A. López-Molina
Keyword(s):  
Cyclic Loading ◽  
Pore Pressure ◽  
Simple Shear ◽  
Colloidal Silica ◽  
Low Cost ◽  
Silty Sand ◽  
Experimental Program ◽  
Shear Tests ◽  
Liquefaction Resistance ◽  
Wide Range

This paper summarizes the experimental results of a series of cyclic simple shear tests on liquefiable silty sand with and without sample improvement with colloidal silica grout. The objective of the paper is to evaluate the effectiveness of colloidal silica grouting in reducing the liquefaction potential of natural silty sand. Colloidal silica was selected as a stabilizing material due to its low viscosity, wide range of gel times, nontoxicity, and low cost. The soil tested in this experimental program is a poorly graded sand with 11.5% of nonplastic silt from the Port of Lázaro Cárdenas, México. Colloidal silica treated and untreated sand specimens show different pore pressure response and deformation behavior under cyclic loading in simple shear tests. The results indicate that, for a given initial relative density and initial effective vertical stress, liquefiable silty sand specimens stabilized with colloidal silica grout generally exhibit significant gain in liquefaction resistance compared with untreated specimens. It was also found that the colloidal silica grout reduces considerably the rates of pore pressure generation and shear strain of the silty sand specimens subjected to cyclic loading.

scholarly journals Influence of Non-Plastic Fines on the Response of a Silty Sand to Cyclic Loading

2010 ◽  
Vol 50 (5) ◽  
pp. 695-704 ◽  
Author(s):  
H.K. Dash ◽  
T.G. Sitharam ◽  
B.A. Baudet
Keyword(s):  
Cyclic Loading ◽  
Silty Sand

scholarly journals Fatigue and damage properties of frozen silty sand samples subjected to cyclic triaxial loading

2016 ◽  
Vol 53 (12) ◽  
pp. 1939-1951 ◽  
Author(s):  
Enlong Liu ◽  
Yuanming Lai ◽  
Mengke Liao ◽  
Xingyan Liu ◽  
Feng Hou
Keyword(s):  
Stress Ratio ◽  
Axial Strain ◽  
Volumetric Strain ◽  
Silty Sand ◽  
Triaxial Tests ◽  
Axial Stiffness ◽  
Cyclic Triaxial ◽  
Cycle Number ◽  
Number Of Cycles ◽  
Strain Method

Cyclic triaxial tests were conducted to explore the influences of dynamic axial loading on the dynamic features and fatigue of frozen silty sand, using an MTS-810 apparatus from Material Testing Systems (MTS). The temperature was −15 °C, and the cyclic axial loads with different amplitudes at 1.0 Hz were applied under confining pressures of 0.6, 1.4, and 6.0 MPa. The cyclic triaxial test results demonstrate that the residual axial strain of the frozen silty sand samples increases gradually during the initial cycles and then increases with increasing number of cycles at a constant speed until failure. The residual volumetric strain contracts during the initial loading cycles and then dilates until failure. Both the residual strain method and the residual volumetric strain method proposed here can be used to describe the degradation process in frozen silty sand samples subjected to cyclic loading. The dynamic axial stiffness of a frozen sample decreases rapidly in the initial cycles and then approaches a stable value with increasing cycle number. The initial damage increases when the stress ratio increases; the larger the stress ratio, the smaller the number of cycles at failure.

scholarly journals Cumulative Plastic Deformation Characteristics of Saturated Silty Sand under Variable Frequency Cyclic Loading of Subway Entrance/Exit

2021 ◽  
Author(s):  
Zeyao Li ◽  
Jie Zhou ◽  
Wanjun Tian ◽  
Yiqun Tang ◽  
Wansheng Pei
Keyword(s):  
Cyclic Loading ◽  
Shear Deformation ◽  
Vibration Amplitude ◽  
Confining Pressure ◽  
Silty Sand ◽  
Experimental Program ◽  
Subway Station ◽  
Variable Frequency ◽  
Deformation Characteristics ◽  
Vertical Deformation

Abstract The acceleration and deceleration movement of the subway near the subway station have a certain impact on the foundation soil. After the samples have been reconstituted in an inclined slope using sand rain method, undrained dynamic cyclic triaxial experiments were designed under specific variable frequency loading condition according to on-site monitoring data and theoretical calculation results. Effects of subway entrance/exit distance, subway entrance/exit acceleration, vibration amplitude, effective confining pressure on the cumulative deformation characteristics of Nanjing saturated silty sand were explored under experimental program. The results show that the cumulative plastic strain development of the Nanjing silty sand under the variable frequency cyclic loading of subway entrance/ exit can be roughly divided into three stages: explosive growth, rapid growth and gradual stability. The increase of the distance from the subway station can reduce the vibration cycles of subway entrance/exit loading to enter the gradual stabilization phase; it can also lower the shear deformation and increase the vertical deformation. Greater the vibration amplitude or lower the effective confining pressure can also have the same effect on soil deformation characteristics. Instead, greater the subway entrance/ exit acceleration, smaller the vertical deformation and larger the shear deformation. For practical engineering, the initial stage of subway line in operation is the focus of engineering geological disaster prevention. The settlement deformation of the soil in subway entrance interval, the horizontal displacement of the soil in subway exit interval are more serious. The soil closer to subway station is more prone to deformation hazard

Sign in / Sign up

Export Citation Format

Share Document