Study of the micro-mechanical behaviour of the Opalinus Clay: an example of co-operation across the ground engineering disciplines

Bock, Helmut; Blümling, P.; Konietzky, Heinz

doi:10.1007/s10064-005-0019-9

Cited by 16 publications

(9 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…One of the most important results of this study for fluid flow and self-sealing models (e.g. Bock et al, 2005) is that in-situ the Main Fault contains a network of shear zones, veins and gouge with a much lower porosity than the protolith. This outcome is consistent with the measurement of no permeability increase in the Main Fault (Nussbaum and Bossart, 2008), but predicts that the present-day permeability of the Main Fault is much lower than that of the protolith.…”

Section: Scaly Claymentioning

confidence: 99%

Microstructural evolution of an incipient fault zone in Opalinus Clay: Insights from an optical and electron microscopic study of ion-beam polished samples from the Main Fault in the Mt-Terri Underground Research Laboratory

Laurich

Urai

Desbois

et al. 2014

Journal of Structural Geology

View full text Add to dashboard Cite

Section: Scaly Claymentioning

confidence: 99%

Microstructural evolution of an incipient fault zone in Opalinus Clay: Insights from an optical and electron microscopic study of ion-beam polished samples from the Main Fault in the Mt-Terri Underground Research Laboratory

Laurich

Urai

Desbois

et al. 2014

Journal of Structural Geology

View full text Add to dashboard Cite

“…Detailed knowledge of rock mechanical behavior and elastic properties is necessary for modeling constructionrelated damage of a future repository site (e.g., Salager et al 2013;Parisio et al 2015). The development of constitutive models predicting long-term integrity and evolution of the host rock rests on micro-mechanical analysis to unravel the physical processes governing deformation (Bock et al 2006). So far, little is known about deformation processes and micromechanics causing anisotropic rheological behavior of experimentally deformed OPA.…”

Section: Introductionmentioning

confidence: 99%

Experimental Deformation of Opalinus Clay at Elevated Temperature and Pressure Conditions: Mechanical Properties and the Influence of Rock Fabric

et al. 2021

View full text Add to dashboard Cite

The mechanical behavior of the sandy facies of Opalinus Clay (OPA) was investigated in 42 triaxial tests performed on dry samples at unconsolidated, undrained conditions at confining pressures (pc) of 50–100 MPa, temperatures (T) between 25 and 200 °C and strain rates ($$\dot{\varepsilon }$$ ε ˙ ) of 1 × 10–3–5 × 10–6 s−1. Using a Paterson-type deformation apparatus, samples oriented at 0°, 45° and 90° to bedding were deformed up to about 15% axial strain. Additionally, the influence of water content, drainage condition and pre-consolidation was investigated at fixed pc–T conditions, using dry and re-saturated samples. Deformed samples display brittle to semi-brittle deformation behavior, characterized by cataclastic flow in quartz-rich sandy layers and granular flow in phyllosilicate-rich layers. Samples loaded parallel to bedding are less compliant compared to the other loading directions. With the exception of samples deformed 45° and 90° to bedding at pc = 100 MPa, strain is localized in discrete shear zones. Compressive strength (σmax) increases with increasing pc, resulting in an internal friction coefficient of ≈ 0.31 for samples deformed at 45° and 90° to bedding, and ≈ 0.44 for samples deformed parallel to bedding. In contrast, pre-consolidation, drainage condition, T and $$\dot{\varepsilon }$$ ε ˙ do not significantly affect deformation behavior of dried samples. However, σmax and Young’s modulus (E) decrease substantially with increasing water saturation. Compared to the clay-rich shaly facies of OPA, sandy facies specimens display higher strength σmax and Young’s modulus E at similar deformation conditions. Strength and Young’s modulus of samples deformed 90° and 45° to bedding are close to the iso-stress Reuss bound, suggesting a strong influence of weak clay-rich layers on the deformation behavior.

show abstract

“…Zhang Minjiang (2005) revealed relations between orientation parameter and macromechanics of micro unit body of soft soil in Yingkou City during the rheological process [3]. H. Bock (2006), by using PFC software, stimulated the shape of clay particles, bound water and free water in soil, as well as the structure of soil particles after deformation [4]. Fang Houguo (2007) studied quantitative index system of microstructure of marine soft soil under different consolidation pressure [5].…”

Section: Fig 1 Sand Grain Mucky Soilmentioning

confidence: 99%

The characteristics of microstructure change of sand grain mucky soil under different consolidation pressures

Li¹,

Zhang²,

Hu³

et al. 2017

MMC_C

View full text Add to dashboard Cite

Sand grain mucky soil is a type of lacustrine sedimentary soft soil of Dongting Lake with a modest layer of silty fine sand in between. It has an unique structure of thin sand layer. In order to study the microstructure particularity of sand grain mucky soil, the paper selects the other three types of Dongting Lake soil as comparison, and collects parameters of equivalent diameter, average roundness, average shape factor and directionality of structure unit body by examining the undisturbed samples and samples under different consolidation pressure of the four types of soil with the use of scanning electron microscope, as well as picture processing technology and mathematical model. At the same time, the paper analyzes relations between surface void ratio, consolidation pressure, and probability entropy and permeability coefficient. The result of the study shows: 1) the main microstructure of sand grain mucky soil is laminated structure; 2) compared with other three types of soil, as consolidation pressure increased, the growth of equivalent diameter of sand grain mucky soil is the fastest in the early stage while slowing down significantly in the later stage, the decreasing range of average roundness is the most, and changes of average shape factor and directionality are the smallest; 3) the effect of different consolidation pressure on surface void ration of sand grain mucky soil is relatively small; 4) the kH and kV of sand grain mucky soil decline as probability entropy decreased, and k-Hm curves of horizontal section and vertical section have big differences due to the modest layer of silty fine sand.

show abstract

Study of the micro-mechanical behaviour of the Opalinus Clay: an example of co-operation across the ground engineering disciplines

Cited by 16 publications

References 3 publications

Microstructural evolution of an incipient fault zone in Opalinus Clay: Insights from an optical and electron microscopic study of ion-beam polished samples from the Main Fault in the Mt-Terri Underground Research Laboratory

Microstructural evolution of an incipient fault zone in Opalinus Clay: Insights from an optical and electron microscopic study of ion-beam polished samples from the Main Fault in the Mt-Terri Underground Research Laboratory

Experimental Deformation of Opalinus Clay at Elevated Temperature and Pressure Conditions: Mechanical Properties and the Influence of Rock Fabric

The characteristics of microstructure change of sand grain mucky soil under different consolidation pressures

Contact Info

Product

Resources

About