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You may decompose the records into two perpendicular directions by cos and sin.

Hi fmk,

The two motions I imposed are actually sinusoidal accelerations with 90 phase difference. The results, such as the settlement and the maximum pore water pressure, are lower than that with single input motion.

Hi fmk, Thanks for your reply. My model is a simplified square elastic column indeed. With same motion imposed in 2 horizontal directions, the join motion will still be unidirectional. The direction will be between those two directions, and the amplitude is their root-mean-square. However, with diff...

Hi everyone, I want to simulate 3D centrifuge experiments with different inputs specified for two directions. Examples on the OpenSees website are for the vertical and one of the horizontal directions(1 and 3). However, I want to impose two horizontal directions perpendicular to each other(1 and 2)....

Hi everyone, I want to simulate an undrained simple shear test of soil under multi-directional shear loading(2D shaking). But there is something wrong with the pattern code: ... timeSeries Sine 1 0 $FTime $period -factor 9.81 ;# FTime is the end time timeSeries Sine 2 [expr $period/4.0] $FTime $peri...

Hi gaziz, I think the PP DOF should be unfixed. I have found two methods to dissipate. One is to change the permeability parameter to a bigger value, like 10 m/s. The other is to use pattern command to impose zero PP to the nodes after undrained loading. However, neither of these are the real dissip...

Hi, The simplified code is as follows: # Create a 3D model with 4 Degrees of Freedom model BasicBuilder -ndm 3 -ndf 4 # Create nodes node 1 1.0 0.0 0.0 node 2 1.0 1.0 0.0 node 3 0.0 1.0 0.0 node 4 0.0 0.0 0.0 node 5 1.0 0.0 1.0 node 6 1.0 1.0 1.0 node 7 0.0 1.0 1.0 node 8 0.0 0.0 1.0 # Create Fixiti...

Hi, I have some ideas about your second question. The parameter-updating command have already been modified. It can only update the permeability parameters of some solid-fluid fully coupled elements, like the quadUP element in your first example. It's nothing to do with the reference bulk modulus of...

Hi, I have built a model to simulate the undrained simple shear test under earthquake loading. At the end of the loading process, the water pressure reached to the peak level. However, as I changed the boundary condation in the following reconsolidation state, the pressure ramained unchanged. I chan...

Hi everyone, Recently, I'm trying to simulate a undrained simple shear test under earthquake loading using the Manzari-Dafalias material. Input parametes are the same as the example gaven in the mannual. However, as the pressure almost reach to the initial vertical pressure, the convergence preblem ...