A two‐surface thermomechanical model for saturated clays

Hong, Peng; Pereira, Jean‐Michel; Cui, Yu-Jun

doi:10.1002/nag.2474

Cited by 22 publications

(15 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the two surface models, the loading surface and the yield surface are geometrically similar in (p', q) plane with a corresponding radial mapping rule. In previous TEAM model [21], two yield limit mechanisms, namely thermal yield limits (ITY, TY) and loading yield limits (ILY, LY) are adopted to model the thermal behavior. These yield limit mechanisms in TEAM model (see Fig.3(a)) enable the thermal elastic response in reloading path to occur before entering the elasto-plastic zone.…”

Section: Yield Limits and Dependency Lawmentioning

confidence: 99%

“…In that case, a similarity between ILY and LY would be recovered. This is just the case of ILY and LY used in TEAM model [21]. 4.…”

Section: Yield Limits and Dependency Lawmentioning

confidence: 99%

“…Observations of different fine-grained soils in the laboratory and in the field [6][7][8][9][10][11] showed that heating generally induced non-negligible volume change and excess pore water pressure buildup. Several thermo-mechanical models were proposed to describe this thermo-mechanical behavior of fine-grained soils [13][14][15][16][17][18][19][20][21]. Some of them extended the Cam-clay or modified Cam-clay model to the temperature effect by introducing a shrinking yield surface [13][14][15][16][17].…”

Section: Introductionmentioning

confidence: 99%

“…In order to well describe the small thermo-mechanical elastic zone and the shear softening behavior, some advanced models consider two yield surfaces based on the bounding surface theory [18][19][20][21]. Hong et al [22] made a comparison among some of these advanced models, and showed that the multiple plastic hardening mechanism were of paramount importance in modeling complex thermal loading behavior.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

A two-surface thermomechanical plasticity model considering thermal cyclic behavior

et al. 2020

View full text Add to dashboard Cite

In thermal-related engineering such as thermal energy structures and nuclear waste disposal, it is essential to well understand volume change and excess pore water pressure buildup of soils under thermal cycles. However, most existing thermomechanical models can merely simulate one heating-cooling cycle and fail in capturing accumulation phenomenon due to multiple thermal cycles. In this study, a two surface elasto-plastic model considering thermal cyclic behavior is proposed. This model is based on the bounding surface plasticity and progressive plasticity by introducing two yield surfaces and two loading yield limits. A dependency law is proposed by linking two loading yield limits with a thermal accumulation parameter nc, allowing the thermal cyclic behavior to be taken into account. Parameter nc controls the evolution rate of the inner loading yield limit approaching the loading yield limit following a thermal loading path. By extending the thermo-hydro-mechanical equations into the elastic-plastic state, the excess pore water pressure buildup of soil due to thermal cycles is also accounted. Then, thermal cycle tests on four fine-grained soils (natural Boom clay, Geneva clay, Bonny silt and reconstituted Pontida clay) under different OCRs and stresses are simulated and compared. The results show that the proposed model can well describe both strain accumulation phenomenon and excess pore water pressure buildup of finegrained soils under the effect of thermal cycles.

show abstract

Section: Yield Limits and Dependency Lawmentioning

confidence: 99%

“…In that case, a similarity between ILY and LY would be recovered. This is just the case of ILY and LY used in TEAM model [21]. 4.…”

Section: Yield Limits and Dependency Lawmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

A two-surface thermomechanical plasticity model considering thermal cyclic behavior

et al. 2020

View full text Add to dashboard Cite

show abstract

“…To accurately predict soil volume changes under thermal cycles is important for analysing the performance of these structures. So far, some thermo‐mechanical soil models have been developed within the elastoplastic framework . Most of these existing models, however, focus on soil behaviour under monotonic thermal loading only.…”

Section: Introductionmentioning

confidence: 99%

A new bounding surface model for thermal cyclic behaviour

Zhou

Fong

2017

Int. J. Numer. Anal. Meth. Geomech.

View full text Add to dashboard Cite

To accurately predict soil volume changes under thermal cycles is of great importance for analysing the performance of many earth structures such as the energy pile and energy storage system. Most of the existing thermo-mechanical models focus on soil behaviour under monotonic thermal loading only, and they are not able to capture soil volume changes under thermal cycles. In this study, a constitutive model is proposed to simulate volume changes of saturated soil subjected to cyclic heating and cooling. Two surfaces are defined and used: a bounding surface and a memory surface. The bounding surface and memory surface are mainly controlled by the preconsolidation pressure (a function of plastic volumetric strain) and the maximum stress experienced by the soil, respectively. Under thermal cycles, the distance of the two surfaces and plastic modulus increase with an accumulation of plastic strain. By adopting the double surface concept, a new elastoplastic model is derived from an existing single bounding surface thermo-mechanical model. Comparisons between model predictions and experimental results reveal that the proposed model is able to capture soil volume changes under thermal cycles well. The plastic strain accumulates under thermal cycles, but at a decreasing rate, until stabilization.

show abstract

Magnitude of latent heat in thermally loaded clays

Samat

Brochard

Stefanou

2020

Num Anal Meth Geomechanics

View full text Add to dashboard Cite

Summary Temperature changes are known to induce specific couplings in clay, in particular, an anomalously high thermal pressurization in undrained conditions or a thermal compaction in drained conditions, both of which are potential threats for the mechanical stability and sealing capacity of the geomaterials. Thermodynamical analysis of those peculiar thermomechanical couplings points to a potentially important latent energy, which in turn could limit the temperature change upon heating or cooling. The direct measurement of latent energy developed during a laboratory geomechanical test is challenging. Instead, proper identification of thermal hardening in conventional experiments with temperature changes provides an alternative route to estimate latent energy. In this work, existing laboratory thermomechanical tests of clays are analyzed with a rigorous thermodynamic framework to quantify the magnitude of latent energy in thermomechanically loaded clays. A thermodynamically consistent constitutive model for fully saturated clays that combines two key features, (a) the temperature dependence of the blocked energy and (b) the framework of bounding plasticity, is proposed. The performance of the model is validated by reproducing results obtained in laboratory tests for Boom and Opalinus clays. The thermomechanical loads considered to validate the model performance were then used to estimate the percentage of work that remains latent in the clayey material during plastic yielding. We find that the magnitude of latent energy is quite significant, typically a few tens of percent of the total dissipated energy, and increases significantly with temperature. Accordingly, it is expected to play an important role in the thermomechanical response of clays.

show abstract

A two‐surface thermomechanical model for saturated clays

Cited by 22 publications

References 30 publications

A two-surface thermomechanical plasticity model considering thermal cyclic behavior

A two-surface thermomechanical plasticity model considering thermal cyclic behavior

A new bounding surface model for thermal cyclic behaviour

Magnitude of latent heat in thermally loaded clays

Contact Info

Product

Resources

About