Finite Element Solutions for Geotechnical Engineering

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Curtis Hudson
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1 Release Notes Release Date: June, 2017 Product Ver.: GTSNX 2017(v1.1) Integrated Solver Otimized for the next generation 64-bit latform Finite Element Solutions for Geotechnical Engineering

2 1. Analysis nc 1.1 Auto Calculation of K 0 and K UBC SAND: Liquefiable Area _ Modified UBC SAND Material 1.3 UBC SAND: Liquefiable Area _ Inut Parameter 2.1 UBC SAND Results : Liquefiable Area and Calibration 2.2 Seeage Cut Off (SCO) element 2.3 Imrovement in History Outut Control 2.4 Flow Quantity Arbitrary Cutting tye 2.5 Imrovement in Extract Results function 2.6 Non-hydrostatic Water Pressure 2.7 Imort/Exort Nodal Results 2.8 Link between LIRA-SPAR / SCAD and midas GTS NX Integrated Solver Otimized for the next generation 64-bit latform Finite Element Solutions for Geotechnical Engineering

3 1. Analysis 1.1 Auto Calculation of K 0 and K 0 nc Earth ressure coefficient K 0 can be calculated automatically based on the other inut arameters such as the friction angle, overconsolidation ratio (OCR) and Poisson's ratio (ν). (Manual inut is also available) In order to aly the K 0 for the calculation of initial stress of the ground, the user must check the K 0 condition otion in analysis control dialog) Material> Coordinate system / Function> Physical roerties> General> Initial stress Material Constitutive Model Automatic calculation of K 0 value Mohr-Coulomb Ducker-Prager Hyerbolic (Duncan-Chang) K 0 nc = 1 sin Automatic calculation of K 0 nc by using frictional angle φ Modified Mohr-Coulomb K 0 nc = 1 sin Soft Soil Soft Soil Cree Hardening Soil (small strain stiffness) Automatic calculation of K nc 0 by using frictional angle φ K 0,x = σ xx 0 0 σ = K 0 nc OCR ν ur OCR 1 yy 1 ν ur Calculates K 0 using K 0 nc and inut OCR K 0 nc = 1 sin K 0 nc = 1 sin = 1 sin30 = 0.5 Generalized SCLAY 1S (MODS) K 0,x = σ xx 0 0 σ = K 0 nc OCR ν ur OCR 1 yy 1 ν ur Manual estimation of K 0 nc Calculates K 0 using K 0 nc, OCR and v [K 0 - automatic calculation] [Auto calculation of K 0 ] 3 / 15

1. Analysis 1.2 UBC SAND: Liquefiable Area _ Modified UBC SAND Material An effective stress model for redicting liquefaction behavior of sand under seismic loading.

Nonlinear Elastic: - Exonential function er effective ressure ne e e ' t G KG ref ref Plasticity / Shear - Yield function : Mohr Coulomb - Flow rule : Menetrey-Willam (non-associated) - Hardening

4 1. Analysis 1.2 UBC SAND: Liquefiable Area _ Modified UBC SAND Material An effective stress model for redicting liquefaction behavior of sand under seismic loading. GTSNX Liquefaction Model is extended to a full 3D imlementation of the modified UBCSAND model using imlicit method. Nonlinear Elastic: - Exonential function er effective ressure ne e e ' t G KG ref ref Plasticity / Shear - Yield function : Mohr Coulomb - Flow rule : Menetrey-Willam (non-associated) - Hardening behavior : Hyerbolic hardening 1 3 n1 G ' sin m sinm s KG 1 Rf s ' ref sin s Plasticity / Comression (ca) - Yield function : Modified Mohr-Coulomb Ca 2 2 q 2 f2 c 0 R2 - Flow rule : Same with yield function (Associated flow) - Hardening behavior : Hardening of allowable comression er volumetric strain m ' c KB ref v ref Plasticity / Pressure cut-off - Yield function & Flow rule 2 ` Cyclic loading behavior - Consider Shear, Plasticity function for rimary and secondary yield surface resectively Check difference of hardening behavior - Primary yield surface: In case that the current stress ratio (or mobilized friction angle) reach to the critical (MAX) state of the material - Secondary yield surface: In case that the current stress ratio is smaller than the critical (MAX) state of the material according to the unloading/reloading conditions - Secondary hardening (Soil Densification) n1 ' sin n1 sin K 1 R, K K 4 F m m G,2 f s G,2 G dens ref sin 2 2 [Primary hardening] [Elastic unloading] [Secondary hardening] f ' r cut - No Hardening behavior 4 / 15

5 2. Post Processing 1.3 UBC SAND: Liquefiable Area _ Inut Parameter Additional arameters to simulate liquefaction Estimation of each arameter using Standard Penetration Test (SPT) - ((N 1 ) 60 : Equivalent SPT blow count for clean sand. Parameter Descrition Reference Pref e K G ne Reference Pressure Elastic (Power Law) Elastic shear modulus number Elastic shear modulus exonent Plastic / Shear In-situ horizontal stress at midlevel of soil layer Dimensionless Dimensionless e KG cv N cv Peak Friction Angle Failure arameter as in MC model Constant Volume Friction Angle - C Cohesion Failure arameter as in MC model K G n R f F ost F dens Plastic shear modulus number Plastic shear modulus exonent Failure ratio (qf / qa) Post Liquefaction Calibration Factor Soil Densification Calibration Factor Advanced arameters ` Dimensionless Dimensionless 0.7~0.98 (< 1), decreases with increasing relative density Residual shear modulus Cyclic Behavior Pcut Plastic/Pressure Cutoff (Tensile Strength) - 2 e KG KG N ne 0.5 n 0.4 cv N N / N cv N1 / 10.0 max 0.0, N R 1.1 N f K B m Ca Bulk Modulus Number - Plastic Ca Modulus Exonent - [Parameters and Equations for Calibration] OCR Over Consolidation Ratio Normal stress / Pre-overburden ressure 5 / 15

2.1 UBC SAND Results : Liquefiable Area Secific results which can check the liquefiable area directly

Pore Pressure Ratio (PPR) - The ratio of excessive ore ressure change and the initial effective ressure

Pore Pressure Change Initial Effective Pressure Current Effective Pressure Normalized Max Stress Ratio

reached, the mobilized friction angle is close to the eak friction angle, liquefaction is triggered (1

6 2.1 UBC SAND Results : Liquefiable Area Secific results which can check the liquefiable area directly Two tyes of results are available to measure the ossibility of liquefaction. Pore Pressure Ratio (PPR) - The ratio of excessive ore ressure change and the initial effective ressure PPR ' ' w init current ' ' init init UBC SAND Layer Mohr Coulomb Layer w ' init ' current Excessive Pore Pressure Change Initial Effective Pressure Current Effective Pressure Normalized Max Stress Ratio - The ratio of mobilized friction angle and the eak friction angle - When the Max stress ratio is reached, the mobilized friction angle is close to the eak friction angle, liquefaction is triggered (1 = Liquefaction) sin m max sin m Mobilized Friction Angle Peak Friction Angle [Nonlinear Time History Analysis under the earth quake] 6 / 15

7 Shear stress [kpa] Shear stress [kpa] GTS NX UBC SAND Results : Liquefiable Area _ Model Calibration Monotonic and cyclic drained Direct Simle Shear (DSS) test (skeleton resonse). Constant volume DSS test (undrained test) 25 Test Analysis 25 Test Analysis ` Shear strain [%] Vertical Stress [kpa] [Undrained DSS (Monotonic)] 15 Soil densification Test Analysis Vertical Stress [kpa] -15 [Undrained DSS (Cyclic)] Vertical Stress [kpa] 7 / 15

2.1 UBC SAND Results : Liquefiable Area _ Case Study Normalized

liquefaction is triggered and is reduced as K G -, where fac os

01 sec] UBC SAND Layer [T = 0.06 sec] m [T = 0.15 sec] [T = 0.

8 2.1 UBC SAND Results : Liquefiable Area _ Case Study Normalized Max Stress Ratio - When the Max ossible stress ratio is reached, liquefaction is triggered and is reduced as K G -, where fac os is a user defined ost liquefaction calibration factor [T = 0.01 sec] UBC SAND Layer [T = 0.06 sec] m [T = 0.15 sec] [T = 0.5 sec] [Nonlinear Time History Analysis under the cyclic loading] 8 / 15

2.2 Seeage Cut Off (SCO) element Seeage Cut Off element is to

The users can define it with 1D and 2D Elements for 2D and 3D

In 2D models, the users can define SCO element from Element

In case of 3D model, the element boundary and Shell element are

Seeage Flow DOF is to decide whether the users allow seeage

(* Effective thickness: When considering seeage flow of SCO

9 2.2 Seeage Cut Off (SCO) element Seeage Cut Off element is to rovide Structural Waterroofing Members. The users can define it with 1D and 2D Elements for 2D and 3D models resectively. In 2D models, the users can define SCO element from Element boundary and Truss/Beam elements. In case of 3D model, the element boundary and Shell element are available to define SCO element. Seeage Flow DOF is to decide whether the users allow seeage flow assing through SCO elements or not. (* Effective thickness: When considering seeage flow of SCO elements, the users should define the effective thickness as the thickness of the structural member.) Mesh > Element > Seeage Cut Off [Model with seeage Cut-Off element] [2D Total Head result] [2D Seeage flow lines] [Seeage Cut Off element and Seeage Flow] [3D model with Seeage Cut Off defined on faces] [3D Total Head result] [3DSeeage flow lines] 9 / 15

2.3 Imrovement in History Outut Control For

check history outut for the secific results

Analysis > Analysis Case > Outut Control >

10 2.3 Imrovement in History Outut Control For the time history analysis, the users can check history outut for the secific results at the secific locations. Once the users define the history outut robes, it will be activated in outut control data automatically. Analysis > History > History Outut Probes Analysis > Analysis Case > Outut Control > History tab [Outut Control] [3D Model] [History Outut Probes] [History Result grah] 10 / 15

Tools > Secial Post > Seeage > Flow Quantity Node / Cutting tye - Calculate the flow quantity by calculating the sum of the flow rate calculated at the selected node.

11 2.4 Flow Quantity Arbitrary cutting tye The users can check the flow quantity assing through any secific locations. In revious versions, the flow quantity was only measurable at the nodes where the users define the boundary conditions. Tools > Secial Post > Seeage > Flow Quantity Node / Cutting tye - Calculate the flow quantity by calculating the sum of the flow rate calculated at the selected node. B A Arbitrary division tye - calculates the flow rate of elements assing through arbitrary lines or faces ( In case of Arbitrary division tye, the users should select the location within the e lements, not the outermost line of the elements.) [Section A Node Mode] [Section B Node Mode] [Section A Cutting Mode] [Section B Cutting Mode] [Section B Arbitrary division] 11 / 15

2.5 Imrovement in Extract Results function When the users change the result tye, all the selected stes had been initialized, so had to select the secific stes again in

12 2.5 Imrovement in Extract Results function When the users change the result tye, all the selected stes had been initialized, so had to select the secific stes again in the revious version. GTSNX 2017 will kee the selected stes even if the users change the result tye. Result > Advanced > Extract GTSNX 2016 GTSNX 2017 Manual Auto 12 / 15

2.6 Non-hydrostatic Water Pressure (Add/Modify Analysis Case > Analysis Control > Define Water Level for Mesh Set > Inut Water Level ) Additional otion to

Head: To set a water level secific to an assigned mesh set with an otion to assign a condition function defined in General Function.

Hydrostatic: To define a ressure value to be alied to the to of an assigned mesh set with a condition function defined in Non-Hydrostatic Water Pressure.

13 2.6 Non-hydrostatic Water Pressure (Add/Modify Analysis Case > Analysis Control > Define Water Level for Mesh Set > Inut Water Level ) Additional otion to allow definition of non-hydrostatic water ressure for secified mesh sets in the analysis control. Head: To set a water level secific to an assigned mesh set with an otion to assign a condition function defined in General Function. Dry: To remove water ressure in the mesh set. Hydrostatic: To define a ressure value to be alied to the to of an assigned mesh set with a condition function defined in Non-Hydrostatic Water Pressure. User Defined: To allow a user defined ressure at to and bottom of an assigned mesh set with a condition function defined in Non-Hydrostatic Water Pressure. [Define multile ressure functions] [Discontinuity in ore water ressure during excavation] [Continuity in ore water ressure using User Defined ressure] [Assign different functions to each mesh set] 13 / 15

2.7 Imort/Exort Nodal Results (Menu > Exort > Exort Nodal Results(*.

txt)) Feature to allow imort and exort of nodal results for nodes with

For exort, users can ot to exort results at all constraint locations or at

Additionally, users can select the analysis set, ste (construction stage),

The develoment allows users to imort nodal results from midas Gen or Civil.

MZ). Dislacements will be imorted as Prescribed Dislacement (Tx, Ty, Tz)

14 2.7 Imort/Exort Nodal Results (Menu > Exort > Exort Nodal Results(*.txt) & Menu > Imort > Imort Nodal Results(*.txt)) Feature to allow imort and exort of nodal results for nodes with constraint defined. For exort, users can ot to exort results at all constraint locations or at selected constraint locations. Additionally, users can select the analysis set, ste (construction stage), result tye (reaction or dislacement), and result comonent for outut. The develoment allows users to imort nodal results from midas Gen or Civil. Reactions will be imorted as Nodal Forces (FX, FY, FZ) and Moments (MX, MY, MZ). Dislacements will be imorted as Prescribed Dislacement (Tx, Ty, Tz) excluding rotation. [Exort] Reactions & Dislacements [Exort Nodal Results otions] [Imort] Nodal Loads & Prescribed Dislacements [Exort results in.txt format] [Analysis Results from Gen/Civil] [Analysis Results from GTS NX] 14 / 15

2.8 Link Between LIRA-SAPR / SCAD and midas GTS NX (Menu > Exort > Execute midas Converter ) This feature

The transfer is carried out through the MIDAS Converter.

The transferred model can be used in midas GTS NX for structure-ground couled analysis, considering

After couled analysis the Converter allows to transfer the obtained results back into the LIRA-SAPR or

The transferred results have format of Subgrade Reaction Modulus for the late elements, Point Srings and

After erforming of analysis in LIRA-SAPR or SCAD with transferred results the analysis results will be the

15 2.8 Link Between LIRA-SAPR / SCAD and midas GTS NX (Menu > Exort > Execute midas Converter ) This feature allows to transfer the structural model from software LIRA-SAPR or SCAD into midas GTS NX. The transfer is carried out through the MIDAS Converter. This Converter transfers such structural model data as elements, materials, sections, boundaries and loads. The transferred model can be used in midas GTS NX for structure-ground couled analysis, considering construction stage consequence. After couled analysis the Converter allows to transfer the obtained results back into the LIRA-SAPR or SCAD software. The transferred results have format of Subgrade Reaction Modulus for the late elements, Point Srings and Satial Dislacements. After erforming of analysis in LIRA-SAPR or SCAD with transferred results the analysis results will be the same as obtained in midas GTS NX. This allows to make structural design in LIRA-SAPR or SCAD software with real behavior of a ground. Examle transferring of model from LIRA-SAPR to midas GTS NX Examle transferring of model from SCAD to midas GTS NX Structure-Ground couled analysis in midas GTS NX Executed Subgrade Reaction Modulus in late elements of building foundation Analysis of model in LIRA-SAPR with transferred results 15 / 15

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