PSI - Issue 6

L.N. Kondratieva et al. / Procedia Structural Integrity 6 (2017) 101–108 L.N. Kondratieva, V.M. Popov,P.Ye. Medvedsky/ StructuralIntegrity Procedia00 (2017) 000 – 000

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4

c)

d)

Vertical stress, kPa

Vertical stress, kPa

0

ξ = 0,43 ξ = 0,54 ξ = 0,67 ξ = 0,72 σ zp 0,2σ zg . . . . .

.

k = 1,0 k = 0,67 k = 0,33 k = 0 σ zp 0,2σ zg . . .

Depth, m

Depth, m

Fig. 2. Dependencies of additional vertical stresses σ vp ( z ) &σ zp ( z ) occurrence in single-layer plastic clay body upon various parameters: а – specific cohesion of soil c at φ = 7°, ξ = 0.67 and k = 0.33; b – internal friction angle φ at с = 29 kPa, ξ = 0.67 and k = 0.33; c – lateral soil pressure coefficient, ξat с = 29 kPa, φ = 7° and k = 0.33; d – soil-to-wall friction coefficient k at с = 29 kPa, φ = 7° and ξ = 0.67 Solid lines indicate stressesσ vp in closed soil body depending on specific cohesion of soil c , internal friction angle φ, lateral soil pressure coefficientξ andservice factor k . Dashed lines indicate stresses in footing without corset σ zp .Dot-and-dash lines indicate epures of five times less vertical stresses occurring caused by own weight of soil. Sheet pile corset is localizing vertical stresses and prevents them from being spread to larger areas, therefore, σ vp stresses occurring in soi l body inside the corset are being attenuated in depth slower than σ zp stresses. When analyzing the plots (Fig. 2) it's possible to point out that σ vp stress attenuation intensity is increasing with increase of specific cohesion c , internal friction angle φ, lateral soil pressure coefficient ξ and service factor k . Considerable impact on stress distribution behaviour σ vp is inflicted by service factor k . Where there is no soil-to-wall friction ( k = 0) it is assumed that σ vp stresses are not attenuating in depth within the closed system. While plotting formula (2) the assumption was made that walls enclosing the soil are rigid and non-deformable.In order to evaluate effect of finite rigidity corset the calculation with the use of Plaxis 3D software was madeBrinkgreve, R. B. J., Engin, E., Swolfs,W. M. (2013). Assumption was made that sheet piling is a geometrically orthotropic structure which can therefore be simulated by slabby elements (Fig. 3).