Taperred Steel Pole

Yes you may define these as tapered tubes ( supports cross sections like round, square, hexagonal, octagonal etc. ) and STAAD.Pro would be able to design these as per codes like AISC 360-05/10.

Can you please check below code, I am trying to use the AISC 360-16 to check the tapered tubular (12 sided Columns, and Beams), however I am still getting the waning messages that "WARNING: DESIGN OF SECTION FOR MEMBER #      1 IS NOT SUPPORTED."

STAAD SPACE TUBULAR MODEL DE
START JOB INFORMATION
ENGINEER DATE 06-Apr-21
JOB CLIENT OKLAHOMA UNIVERSITY
JOB NO CEES 5970
ENGINEER NAME MUSTAFA ALI NEHAID
END JOB INFORMATION
***********************************************
* STAAD.Pro Generated Comment *
***********************************************
* 3 0 20 0 6 30 20 0
***********************************************
OUTPUT WIDTH 72
UNIT FEET KIP
JOINT COORDINATES
1 0 0 0; 2 36 0 0; 3 0 36 0; 4 8 36 0; 5 18 36 0; 6 36 36 0; 7 0 43 0;
8 36 43 0; 9 8 43 0; 10 28 43 0; 11 18 43 0; 17 0 53 0; 18 36 53 0;
19 0 63 0; 20 36 63 0; 21 72 53 0; 22 72 0 0; 23 72 63 0; 24 72 36 0;
25 72 43 0; 26 28 36 0; 27 64 36 0; 28 54 36 0; 29 64 43 0; 30 44 43 0;
31 54 43 0; 32 44 36 0;
MEMBER INCIDENCES
1 1 3; 2 3 7; 3 2 6; 5 3 4; 6 4 5; 7 5 26; 20 7 9; 21 9 11; 22 10 11;
23 8 10; 24 7 17; 25 17 19; 27 18 20; 28 6 8; 29 8 18; 30 8 30; 31 6 32;
32 22 24; 33 24 25; 34 25 21; 35 21 23; 36 26 6; 37 27 24; 38 28 27;
39 29 25; 40 30 31; 41 31 29; 42 32 28;
MEMBER PROPERTY
5 TO 7 20 TO 23 30 31 36 TO 42 PRIS DOD STA 1 END 1 THI 0.02
1 3 32 PRIS DOD STA 2.75 END 1.815 THI 0.02
2 28 33 PRIS DOD STA 1.815 END 1.702 THI 0.02
24 29 34 PRIS DOD STA 1.702 END 1.34 THI 0.02
MEMBER PROPERTY AMERICAN
25 27 35 TABLE ST PIPS20
*MEMB TRUSS
*14 TO 23
UNIT INCHES KIP
DEFINE MATERIAL START
ISOTROPIC STEEL
E 29000
POISSON 0.3
DENSITY 0.000283
ALPHA 6e-06
DAMP 0.03
TYPE STEEL
STRENGTH FY 36 FU 58 RY 1.5 RT 1.2
ISOTROPIC STEEL_65KSI
E 29000
POISSON 0.3
DENSITY 0.000283
ALPHA 6.5e-06
DAMP 0.03
G 11153.8
TYPE STEEL
STRENGTH FY 65 FU 80 RY 1 RT 1
END DEFINE MATERIAL
UNIT FEET KIP
CONSTANTS
MATERIAL STEEL MEMB 25 27 35
MATERIAL STEEL_65KSI MEMB 1 TO 3 5 TO 7 20 TO 24 28 TO 34 36 TO 42
SUPPORTS
1 2 22 FIXED
LOAD 1 DEAD AND LIVE LOAD
SELFWEIGHT Y -1.15
LOAD 2 WIND FROM LEFT
LOAD 3 LOADTYPE None TITLE LOAD CASE 4 WIRE TENSION
JOINT LOAD
9 TO 11 29 TO 31 FX 0.287 FY -1.434 FZ 4
17 18 21 FX 0.2 FY -1 FZ 3
4 5 9 TO 11 26 TO 32 FX 0.2 FY -1
LOAD COMB 4 COMBINATION LOAD CASE 4
1 1.0 2 1.0 3 1.0
PERFORM ANALYSIS
*CODE ASCE 1997
*CODE LRFD
PARAMETER 1
CODE AISC UNIFIED 2016
CHECK CODE ALL
*CODE ASCE 1997
PARAMETER 2
CODE LRFD
STEEL MEMBER TAKE OFF ALL
*CODE ASCE 1997
PARAMETER 3
CODE LRFD
STEEL TAKE OFF ALL
FINISH