Effect of repeated loading on the strength of clay

Toğrol, Ergün; Güler, Erol

doi:10.1016/0261-7277(84)90034-2

Cited by 8 publications

(4 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Induced overconsolidation was considered to be the primary mechanism for strength loss in such cases. Togrol and Güler (1984) and Li et al (2011) similarly explained their observed reduction in strength following cyclic loading as a function of induced overconsolidation. Ward (1983) found normalised pore water pressure behaviour at failure (quantified by Skempton's pore water pressure parameter, A) was similar between overconsolidated and post-cyclic samples.…”

Section: 1: Pore Water Pressure Stress Path and Resilient Strain Rmentioning

confidence: 65%

“…Static strength of normally consolidated soil has been observed to reduce following large cyclically-induced strains and pore water pressures, (e.g. Brown et al 1977;Togrol and Güler 1984;Andersen et al, 1988;Li et al 2011). Ward (1983) found samples accumulating sufficient pore water pressure failed on the Hvorslev surface under subsequent static load, at lower deviator stress than the critical state.…”

Section: 1: Pore Water Pressure Stress Path and Resilient Strain Rmentioning

confidence: 99%

See 1 more Smart Citation

Degradation of soft subgrade soil from slow, large, cyclic heavy-haul road loads: a review

et al. 2016

View full text Add to dashboard Cite

Extraction of resources in remote locations can require temporary haul roads to transport extremely large, slow-moving, indivisible loads (e.g., plant, oil–gas production modules, and reactors, weighing in excess of 1000 t) without interruptions. Poor subgrade soils may experience larger cyclic strains and greater cyclic degradation under these conditions than under conventional roads, yet the short engineering life precludes many foundation-strengthening options due to cost. As there is little research into this unique situation, this paper synthesizes research from a broad range of applications to discuss implications on expected soil response. Reference is made to critical state theory and discrete element method (DEM) modelling to develop fundamental concepts considering particle-scale interactions. Cyclic failure is proposed to be a kinematically unstable process, triggered by shear banding on the Hvorslev surface, tensile liquefaction or fabric-governed meta-stable liquefaction; the latter is particularly influenced by stress history and anisotropy. This paper finds pore-water pressure accumulation under load and dissipation between loads are key to cyclic degradation and furthermore to be dependent upon load duration, principal stress rotation, and repetition frequency. For meta-stable, liquefiable soils in particular, inclination of principal stresses is at least as important in assessing failure risk as magnitude of stresses.

show abstract

Section: 1: Pore Water Pressure Stress Path and Resilient Strain Rmentioning

confidence: 65%

Section: 1: Pore Water Pressure Stress Path and Resilient Strain Rmentioning

confidence: 99%

Degradation of soft subgrade soil from slow, large, cyclic heavy-haul road loads: a review

et al. 2016

View full text Add to dashboard Cite

show abstract

“…If cyclic loading is sufficient to trigger liquefaction, the response to subsequent monotonic loading is much more dilatant and brittle than the monotonic response of intact (i.e. no cyclic stage) samples (Figure 16), implying induced overconsolidation similar to that observed by Ward (1983), Togrol and Güler (1984) and Li et al (2011). It is apparent that the sum of cyclic plastic and monotonic strains governs shear band initiation; dilating soil requires large localised grain movements (i.e.…”

Section: Behaviour Changes From Cyclic Pre-loadingmentioning

confidence: 69%

“…Post-cyclic monotonic tests (Ward, 1983;Togrol and Güler, 1984;Wang et al, 2015) indicate that raising pore water pressures through cyclic pre-loading results in similar monotonic shear response to samples overconsolidated by removal of the same external stress. Cyclic loading can reduce the post-cyclic monotonic strength if strains are high (Brown et al, 1977;Díaz-Rodríguez and Santamarina, 2001;Santagata and Germaine, 2005) but can also improve strength if plastic cyclic strains are sufficiently low (e.g.…”

Section: Initiating and Averting Metastable Liquefactionmentioning

confidence: 99%

Controlled heavy-haul traffic loading as a method to remediate liquefiable soft silts

2019

View full text Add to dashboard Cite

Transporting of extremely large indivisible loads (10 000–30 000 t) is becoming increasingly popular to allow offsite modular construction of infrastructure for oil and gas, mining, and renewable energy projects in remote areas. Such exceptionally large transient loads could encounter unusual geohazards: there is a risk of metastable liquefaction when crossing soft alluvium, causing sudden failure, potential casualties, and severe production delays. Furthermore, temporary roads for these payloads are a large cost to such projects; conventionally designed earthworks and (or) ground improvement are often unaffordable or logistically impossible. This laboratory study indicates the fabric can be strengthened, and the hazard reduced, if the soil is subjected to careful repeated loading that rearranges the initially precarious fabric through gradual accumulation of plastic strains. A novel remediation technique for these temporary haul roads is proposed: managed deployment of increasingly heavy haul vehicles could result in staged fabric rearrangement that strengthens the soil to the point where it would be safe for the heavy vehicles to use it. In so doing, a more economic temporary haul road is open to operations (coupled with observation methods to ensure adequate performance throughout) and production activities are not overly disrupted.

show abstract