Field Tests on Laterally Loaded Piles in Sand and Clay

Laterally loaded piles in permafrost

Canadian Geotechnical Journal ◽

10.1139/t84-047 ◽

1984 ◽

Vol 21 (3) ◽

pp. 431-438 ◽

Cited By ~ 16

Author(s):

J. F. (Derick) Nixon

Keyword(s):

Numerical Procedure ◽

Ground Surface ◽

Surface Displacement ◽

Field Tests ◽

Creep Model ◽

Sustained Load ◽

Laboratory Model ◽

Secondary Creep ◽

Laterally Loaded Piles ◽

Laterally Loaded

A theory for the design of laterally loaded piles in permafrost is presented. The approach is valid for icy soils or ice, where secondary creep displacements will be responsible for the majority of the soil strain under sustained load. Initially, the paper studies in some detail the response of a short, rigid pile embedded in a nonlinear viscous medium. The concept of a flexible elastic pile in a viscous continuum is then introduced, and a relatively straightforward numerical procedure must be introduced to obtain a solution. Once the limiting or design ground surface displacement rate is established by the designer, the paper shows how a typical chart relating lateral pile load to average ground temperature can be prepared.The available (but limited) data base is reviewed for field pile load tests carried out in the early 1970's in Inuvik, N.W.T. and some laboratory model pile tests carried out in connection with this study. Using available long-term secondary creep data for ice and icy silts, predictions for the lateral creep response of piles can be carried out. Agreement between prediction and observation is certainly encouraging and points the way to further research and field testing in this area. Finally, the paper briefly discusses the resistance of rigid fixed-headed piles to lateral loads, and the resistance of a pile in permafrost to the application of a pure moment. Key words: lateral piles, permafrost, creep, model, field tests.

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A Simplified Calculation Method for the Near-Slope Laterally Loaded Pile Based on a Passive Wedge Model

Advances in Civil Engineering ◽

10.1155/2019/8363252 ◽

2019 ◽

Vol 2019 ◽

pp. 1-10 ◽

Cited By ~ 1

Author(s):

Minghui Yang ◽

Bo Deng ◽

Yuhui Wang

Keyword(s):

Slope Angle ◽

Field Tests ◽

Internal Force ◽

Laboratory Model ◽

Loading Capacity ◽

Soil Resistance ◽

Laterally Loaded Piles ◽

Solution Methods ◽

Simplified Calculation ◽

Laterally Loaded

When a pile is placed near the slope, the lateral loading capacity of the pile decreases significantly due to the weakening effect of soil resistance near the slope. As such, a modified soil passive wedge model for near-slope laterally loaded piles is presented to consider the weakening effect in this paper. According to development depth of different wedges, the shapes of soil passive wedge can be classified into three sorts, so as to fully analyze the influence of the slope shape and the distance from the pile center to the slope crest. On this basis, a concept of equivalent depth is proposed considering the differences of laterally loaded piles near the slope and in the horizontal ground. Besides, the unit ultimate soil resistance, which can be obtained along the different depths of pile, is introduced into the p-y curve of the soil, for achieving solution methods of internal force and displacement of laterally loaded piles under the slope weakening effect. The results of laboratory model and field tests on laterally loaded piles are compared with the proposed method, demonstrating its validity and accuracy. Furthermore, the influence of the near-slope distance on the loading capacity of the pile is fully analyzed in detail, indicating the critical near-slope distance is increasing with the increase of the undrained strength, while independent of the slope angle.

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