** WARNING - SOIL SOL1 CONTAINS STRATA FOR WHICH API RP2A-WSD 21 Supp. 3 RECOMMENDS THE USE OF CPT-BASED METHODS
also this error
JOINT 101 AT DOF DX*** ERROR-STIFFNESS MATRIX IS SINGULAR
Any suggestion how to resolve this
The first message is just a warning indicating that the methods used to generate the P-Y or T_Z curves falls outside of the validity range and the CPT method is recommended instead. This will not cause the analysis to fail.
The second error indicates that there is instability at the pile tip. I see a ‘Y’ option on the SOIL LATERAL HEAD line which I believe will modify the stiffness at the pile tip. I can’t say for sure because I can’t see exactly what column it’s in. Try changing that option to ‘N’ and see if you get the solution to converge.
Regards,
Geoff
Thanks Geoff
Done that & still get the same warning and error re singularity. My main issue was why the example/sample problem two in SACS manual does not even run with the SPI SACS program. I had a different problem that I was solving using PSI. I kept getting errors which did not make sense and just to test PSI I run the sample problem hoping I can run that & then modify the file to run my problem. I both cases the program keep giving me errors.
PLOPT ENUC PLTRQ SD PLGRUP PLGRUP PL1 28.0 1.00 50.0 50.0 PLGRUP PL1 28.0 0.75 36.0 175.0 PILE PILE 2 201 PL1 1.0 1.0 8.0 SOL1 SOIL ICP SOIL AXIAL HEAD 8 SOL1 ICP SOIL API AXL SLOC 0.001 20.0 SILT 1.0 50.0 SOIL API AXL SLOC 20.00 60.00 SNSL 1.0 100.0 SOIL API AXL SLOC 160.0 SLSN 1.0 40.0 SOIL API AXL SLOC 200.0 SAND 0.9 80.0 SOIL API AXL SLOC 228.0 CLOC 20.0 50.0 SOIL API AXL SLOC 260.0 CLUC 40.0 70.0 SOIL API AXL SLOC 300.0 CLAY 70.0 90.0 SOIL API AXL SLOC 400.0 ROCK 100.0 200.0 100.0 SOIL TORSION HEAD 1000.0SOL1 SOIL LATERAL HEAD 6 28. SOL1 SOIL API LAT SLOC SILTSA 20. 0.5 50.0 20.0 SOIL API LAT SLOC SNSLCA 20.0 1.0 60.0 60.0 SOIL API LAT SLOC SLSNSA 60.0 1.5 70.0 125.0 SOIL API LAT SLOC SANDSA 120.0 140.0 1.75 80.0 125.0 SOIL API LAT SLOC SANDSA 140.0 2.00 80.0 125.0 SOIL API LAT SLOC CLAYS 200.0 3.00 100.0 0.250 0.001 PLSTUB D1002 2.2802 0.01306 625.4 END
My original problem was a simple pile but I keep getting error in line 4 re format but do not know what is wrong
PSIOPT METC Y EX S3 PLTRQ SD PLGRUP PLGRUP PL1 40.64 1.0 27.5 36. SOIL SOIL AXIAL HEAD 2 2.039 SOL1 ICP SOIL API AXL SLOC 8.0 20.0 SAND 1.O SOIL API AXL SLOC 20.00 36. CLAY 70.0 2.36 PLSTUB FD1002 10.0 100.0 END