Laserfiche WebLink
Procedure for the evaluation of soil liquefaction resistance, NCEER (1998) <br />Calculation of soil resistance against liquefaction is performed according to the Robertson & Wride (1998) procedure. The <br />procedure used in the software, slightly differs from the one originally published in NCEER-97-0022 (Proceedings of the NCEER <br />Workshop on Evaluation of Liquefadion Resistance of Soils). The revised procedure is presented below in the form of a <br />flowchartl: <br />qc: tip resistance, f, : sleeve friction <br />6,.w er,.0' : in-situ vertical total and effective stress <br />units : all in kPa <br />initial stress exponcn¢' :n= 1.0 and calculate Q, F. and Ic <br />if 4 5 1.64. n = 0.5 <br />if 1.64 < Ic < 3.30. n = (4-1.64)0.3 + 0.5 <br />ific 2 3.30, n = 1.0 <br />iterate until the change in n. An < 0.01 <br />if am' > 300 kfa. let n= 1.0 for all soils <br />"updated from <br />Robenson and <br />Wride (1998) C <br />F1 C.0' J. <br />(n F=100ft <br />100 (qc - a,o ) <br />/c = VI[3.47 - log Q)2 + 0.22 + log F)2 J <br />V <br />if Ic S ] ·64. Kc = 1.0 <br />if 1.64 < ic < 2.60. Kc = -O,403 17 + 5.581 12 -21.63 42 + 33.75 10 - 17.88 <br />if Ic 2 2.60. evaluate using other criteria; likely nonliquefiable if F> 1% <br />BUT, if 1.64 < 4 < 2.36 8231 F < 0.5%, set Kc = 1.0 <br />Cqr]N)£, = KCQ <br />. <br />CRE-1,5 = 93· C9,·1•.')c, + 0.08. if 50 5 (qc,N)©5 < 1601000 <br />CRR7.5= 0.833 - <fic],%·)£-t -1 + 0.05, if (clciN)es < 50L 1000 j <br />ifle 2 2.60, evalu'ate using Other criteria; likely nonliquifiable if F > 1% <br />1 "Estimating liquefadion-induced ground settlerrents from (PT for level ground", G Zhang, P. IC Robertson, and R.W. I. Brachnen <br />CUq v. 1.5.1.16 - CFT- Uquefaction Assessment Software 49 <br />SL Rvcd 2019.01.21