SlipSurface IQ Liquefaction — reference

Inputs

• Design earthquake: moment magnitude M_w; peak ground acceleration a_max, entered or taken as 0.4·S_DS (TBDY 2018).
• Groundwater: the water table during the earthquake and when the SPT was made; γ_w.
• Field test: SPT or CPT.
• SPT set-up: hammer energy ratio ER, borehole diameter, rod length above the ground, the short-rod correction, liners in the sampler, and the gravel correction.
• CPT set-up: net area ratio of the cone, the I_c limit of clay-like soils, C_FC (fines content from I_c), and N_kt for s_u.
• Ground geometry: level, a gentle slope S, or a free face of height H at distance L.
• Soil profile, from the surface down: thickness, γ, γ_sat, fines content FC, clay fraction, LL, PI, natural water content w_n and, if measured, V_s; D₅₀ (gravel); OCR and s_u of the clay-like layers.
• SPT tests: depth and field blow count N; FC, clay, LL, PI and w_n of the sample itself where they were measured.
• CPT sounding: depth, q_c (MPa), f_s (kPa) and u₂ (kPa); pasted from a spreadsheet or imported from CSV.
• Options: the triggering procedure, the fine-grained soil criterion, the depth of the settlement; for Cetin et al., the probability of liquefaction.
• Criteria: the required factor of safety and the allowable settlement.

What it computes

Quantity	Method
Stresses	σv, u, σ′v with the design water table; σ′v with the water table of the test for CN
N60	N·CE·CB·CR·CS (Youd et al. 2001; CS of Seed et al. 1984)
(N1)60, (N1)60cs	CN = (Pa/σ′v)m ≤ 1.7; fines correction of IB 2014 or Youd et al. (2001)
CSR	0.65·(amax/g)·(σv/σ′v)·rd; rd of Idriss (1999), Liao & Whitman, Cetin et al. (2004) or TBDY
CRR	IB 2014 with MSF and Kσ; NCEER; Cetin et al. (2004); TBDY 2018; Andrus & Stokoe (2000) from Vs
Susceptibility	Bray & Sancio (2006); Boulanger & Idriss (2006); Seed et al. (2003); Andrews & Martin (2000); Chinese criteria
Volumetric strain	Ishihara & Yoshimine (1992), as fitted by Yoshimine et al. (2006)
Settlement	Σ εv·Δz below the water table to the chosen depth
LPI, LSN	Iwasaki et al. (1978); van Ballegooy et al. (2014)
CPT	Ic of Robertson & Wride (1998) / Robertson (2009); FC = 80·(Ic + CFC) − 137; IB 2014 CPT or Robertson & Wride
Cyclic softening	Boulanger & Idriss (2007): CRR = 0.8·(su/σ′v)·MSFclay
Dry sand	Pradel (1998)
Lateral spreading	Zhang et al. (2004): LDI = ∫ γmax dz; LD = (S + 0.2)·LDI or 6·(L/H)−0.8·LDI
Gravel	N reduced by 1 − 0.36·log10(D50/2) for D50 ≥ 2 mm (JRA 1996)

Figures

Borehole log · factor of safety with depth, the liquefied zones shaded · CSR against CRR · N, N₆₀, (N₁)₆₀ and (N₁)_60cs · volumetric strain and settlement · LPI and LSN with depth · factor of safety by every procedure · the fine-grained samples on the plasticity chart and on Bray & Sancio's chart · γ_max and the lateral displacement index · for a CPT, q_c, f_s and I_c with depth and Robertson's soil behaviour type chart. Study figures: one-at-a-time sweep, histogram, scatter, tornado.

Reports

PDF, self-contained HTML or Word: the inputs, the susceptibility of every sample, the triggering calculation test by test (σ_v, σ′_v, N₆₀, (N₁)₆₀, (N₁)_60cs, r_d, CSR, CRR_7.5, MSF, K_σ, CRR, FS), strain and settlement, LPI and LSN, the comparison of the procedures, the checks, the figures, the warnings, the method notes and — if one was run — the study.