Hi everyone,

I’m trying to connect a shell element (SHELL181) with multiple beam elements (BEAM188) in ANSYS MAPDL.

My current approach:

• I generate the initial and final coordinates for the beam elements.
• I create a shell mesh with a density of 0.1, which results in multiple nodes within the shell and unnecessary elements.
• I ensure the connection by aligning the beam nodes with the shell mesh nodes and then merging them.

This method works, but I’m wondering if there is a more efficient way to achieve this.

My questions:

Any insights or best practices would be greatly appreciated!

Thanks in advance!

Note: You may see several warnings about non-ascending coordinates, but this is expected, and the code will run correctly.

CODE:

FINISH

/CLEAR,NOSTART

/PREP7

/TITLE, Pile and Shell Analysis

! Units in N and m

/UNITS, SI

! Define the element type (BEAM188) and its properties

ET, 1, BEAM188

! Material properties

MP, EX, 1, 0.85*5600*SQRT(40)*1e+6 ! Elastic modulus in Pa (N/m²) - 30104.88332 MPa

MP, PRXY, 1, 0.2 ! Poisson's ratio

MP, DENS, 1, 2500 ! Density in kg/m³ (adjust as needed)

! Beam section properties in centimeters

SECTYPE, 1, BEAM, CSOLID

SECOFFSET, CENT

SECDATA, 0.5

! Define initial points

*SET, x_initials, 0.8, 0.8, 0.8, 3.3, 4.2, 4.2, 7.4, 7.4

*SET, y_initials, -1.8, 0.0, 1.8, 0.0, 1.8, -1.8, -2.5, 2.5

*SET, z_initials, -0.01, -0.01, -0.01, -0.01, -0.01, -0.01, -0.01, -0.01

! Define final points with 35 m long vectors (rounded to 2 decimal places)

*SET, x_finals, -7.12, 9.33, -7.12, 11.83, 10.66, 10.66, 2.47, 2.47

*SET, y_finals, -4.67, 0.00, 4.63, 0.00, 7.21, -7.21, -9.45, 9.45

*SET, z_finals, -33.94, -33.94, -33.94, -33.94, -33.94, -33.94, -33.94, -33.94

! Number of intermediate nodes to be created

num_intermediate_nodes = 9

! Initialize node_id

node_id = 1

*DO, i, 1, 8, 1

x_initial = x_initials(i)

y_initial = y_initials(i)

z_initial = z_initials(i)

x_final = x_finals(i)

y_final = y_finals(i)

z_final = z_finals(i)

! Add the initial node

N, node_id, x_initial, y_initial, z_initial

! Add the final node

node_id_final = node_id + num_intermediate_nodes + 1

N, node_id_final, x_final, y_final, z_final

! Constrain the final nodes

D, node_id_final, ALL, 0

! Fill intermediate nodes

FILL, node_id, node_id_final, num_intermediate_nodes

! Update node_id for the next iteration

node_id = node_id_final + 1

*ENDDO

! Generate elements

n_element = 1

*DO, i, 1, 8, 1

*DO, j, 1, num_intermediate_nodes+1, 1

N_1 = j + (num_intermediate_nodes+2)*(i-1)

N_2 = N_1 + 1

EN, n_element, N_1, N_2

n_element = n_element + 1

*ENDDO

*ENDDO

! Select BEAM188 elements

ESEL, S, TYPE, , 1

! Get the number of selected elements and store in a variable

*GET, num_elem, ELEM, 0, COUNT

k = num_elem

! Create load application element (Bollard)

N, 1000, 6.5, 0, 0

N, 1001, 6.5, 0, 1.5

EN, k+1, 1000, 1001

l=9

! Create load application element (Fender)

N, 1002, l, 0, 0

N, 1003, l, 0, -1

EN, k+2, 1002, 1003

! Define element type (SHELL181) and material properties for the shell

ET, 2, SHELL181

KEYOPT, 2, 8, 2

KEYOPT, 2, 3, 2

! Material properties for SHELL181

MP, EX, 2, 0.85*5600*SQRT(20)*1e+6

MP, PRXY, 2, 0.2

MP, DENS, 2, 2500

! Define shell section

SECTYPE, 2, SHELL

SECDATA, 1.5

! Create rectangle and shell mesh

RECTNG, 0, l, -3.5, 3.5

ESIZE, 0.1

AMESH, ALL

! Select elements whose centers are within the Z range

ESEL, S, TYPE,,2

! Modify section of selected elements

EMODIF, ALL, SECNUM, 2

! Merge nodes

NSEL, S, LOC, Z, -0.01, 0.01

NUMMRG, NODE, 0.01

NSEL, ALL

! Output nodes and elements

ALLSEL,ALL

/STAT,GLOBAL

NLIST,ALL, , ,XYZ,NODE,NODE,NODE

ELIST,ALL,,,0,0

ACEL, 0, 0, -9.81

FINISH

! Solution

/SOLU

ANTYPE,0

j = 1

! Calculate angle in radians for j=1

Rad = (j-1)*10*3.14159265359/180

! Define force (1 million N, negative sign)

f = -1000000

! Calculate horizontal force components

FX = SIN(Rad)*f

FY = COS(Rad)*f

! Select all elements

ALLSEL, ALL

! Apply horizontal forces at node 1001

F, 1001, FX, FX

F, 1001, FY, FY

! Solve the model

SOLVE

! Save solution results for load step 1

SAVE, 'load_step_1'

FINISH

!POST

/POST1

set,1

ESEL, S, TYPE, , 1 ! Select only BEAM188 elements

ETABLE, Fx_MAX, SMISC, 1, ABSMAX ! Maximum axial force

ETABLE, My_MAX, SMISC, 2, MAX ! Maximum bending moment in Y

ETABLE, Mz_MAX, SMISC, 3, MAX ! Maximum bending moment in Z

ETABLE, Fx_MIN, SMISC, 1, ABSMIN ! Minimum axial force

ETABLE, My_MIN, SMISC, 2, MIN ! Minimum bending moment in Y

ETABLE, Mz_MIN, SMISC, 3, MIN ! Minimum bending moment in Z

ETABLE, U_X, U, X

ETABLE, U_Y, U, Y

ETABLE, U_Z, U, Z

! Display ETABLE results for bending moments, axial force, and displacements

PRETAB, Fx_MAX, Fx_MIN, My_MAX, My_MIN, Mz_MAX, Mz_MIN, U_X, U_Y, U_Z

! Display displacement vector field

PRNSOL, U

! Display displacement, rotation, and stress vectors

PRVECT, U ! Displacement vectors

PRVECT, ROT ! Rotation vectors

! Print nodal results for displacements, rotations, and stresses

PRNSOL, U, COMP ! Displacements by component

PRNSOL, ROT, COMP ! Rotations by component

PRNSOL, S, COMP ! Stresses by component

! Constrained nodes

PRRSOL,F