def concrete_circular_section(
d: float,
n: int,
dia: float,
n_bar: int,
n_circle: int,
cover: float,
area_conc: float = None,
area_bar: float = None,
conc_mat: pre.Material = pre.DEFAULT_MATERIAL,
steel_mat: pre.Material = pre.DEFAULT_MATERIAL,
) -> geometry.CompoundGeometry:
"""Constructs a concrete circular section of diameter *d* discretised with *n*
points, with *n_bar* steel bars of diameter *dia*, discretised with *n_circle*
points with equal side and bottom *cover* to the steel.
:param float d: Concrete diameter
:param float n: Number of points discretising the concrete section
:param float dia: Diameter of the steel reinforcing bars
:param int n_bar: Number of steel reinforcing bars
:param int n_circle: Number of points discretising the steel reinforcing bars
:param float cover: Side and bottom cover to the steel reinforcing bars
:param float area_conc: If provided, constructs the concrete based on its area
rather than diameter (prevents the underestimation of concrete area due to
circle discretisation)
:param float area_bar: If provided, constructs reinforcing bars based on their area
rather than diameter (prevents the underestimation of steel area due to
:param Optional[sectionproperties.pre.pre.Material] conc_mat: Material to associate
with the concrete
:param Optional[sectionproperties.pre.pre.Material] steel_mat: Material to
associate with the steel
:raises ValueErorr: If the number of bars is not greater than or equal to 2
The following example creates a 450DIA concrete column with with 6N20 steel
reinforcing bars and 45 mm cover::
from sectionproperties.pre.library.concrete_sections import concrete_circular_section
from sectionproperties.pre.pre import Material
concrete = Material(
name='Concrete', elastic_modulus=30.1e3, poissons_ratio=0.2, yield_strength=32,
density=2.4e-6, color='lightgrey'
)
steel = Material(
name='Steel', elastic_modulus=200e3, poissons_ratio=0.3, yield_strength=500,
density=7.85e-6, color='grey'
)
geometry = concrete_circular_section(
d=450, n=64, dia=20, n_bar=6, n_circle=24, cover=45, conc_mat=concrete, steel_mat=steel
)
geometry.create_mesh(mesh_sizes=[500])
.. figure:: ../images/sections/concrete_circular_section_geometry.png
:align: center
:scale: 50 %
Concrete circular section geometry.
.. figure:: ../images/sections/concrete_circular_section_mesh.png
:align: center
:scale: 50 %
Mesh generated from the above geometry.
"""
if n_bar < 2:
raise ValueError("Please provide 2 or more steel reinforcing bars.")
# create circular geometry
if area_conc:
geom = primitive_sections.circular_section_by_area(area=area_conc,
n=n,
material=conc_mat)
else:
geom = primitive_sections.circular_section(d=d, n=n, material=conc_mat)
# calculate bar geometry
r = d / 2 - cover - dia / 2
d_theta = 2 * np.pi / n_bar
for i in range(n_bar):
if area_bar:
bar = primitive_sections.circular_section_by_area(
area=area_bar, n=n_circle, material=steel_mat)
else:
bar = primitive_sections.circular_section(d=dia,
n=n_circle,
material=steel_mat)
bar = bar.shift_section(x_offset=r * np.cos(i * d_theta),
y_offset=r * np.sin(i * d_theta))
geom = (geom - bar) + bar
return geom
def concrete_tee_section(
b: float,
d: float,
b_f: float,
d_f: float,
dia: float,
n_bar: int,
n_circle: int,
cover: float,
conc_mat: pre.Material = pre.DEFAULT_MATERIAL,
steel_mat: pre.Material = pre.DEFAULT_MATERIAL,
) -> geometry.CompoundGeometry:
"""Constructs a concrete tee section of width *b*, depth *d*, flange width *b_f* and flange
depth *d_f* with *n_bar* steel bars of diameter *dia*, discretised with *n_circle* points with
equal side and bottom *cover* to the steel.
:param float b: Concrete section depth
:param float d: Concrete section width
:param float b_f: Concrete section flange depth
:param float d_f: Concrete section flange width
:param float dia: Diameter of the steel reinforcing bars
:param int n_bar: Number of steel reinforcing bars
:param int n_circle: Number of points discretising the steel reinforcing bars
:param float cover: Side and bottom cover to the steel reinforcing bars
:param Optional[sectionproperties.pre.pre.Material] conc_mat: Material to associate with
the concrete
:param Optional[sectionproperties.pre.pre.Material] steel_mat: Material to associate with
the steel
:raises ValueErorr: If the number of bars is not greater than or equal to 2
The following example creates a 900D x 450W concrete beam with a 1200W x 250D flange, with 5N24
steel reinforcing bars and 30 mm cover::
from sectionproperties.pre.library.concrete_sections import concrete_tee_section
from sectionproperties.pre.pre import Material
concrete = Material(
name='Concrete', elastic_modulus=30.1e3, poissons_ratio=0.2, yield_strength=32, color='lightgrey'
)
steel = Material(
name='Steel', elastic_modulus=200e3, poissons_ratio=0.3, yield_strength=500, color='grey'
)
geometry = concrete_tee_section(
b=450, d=900, b_f=1200, d_f=250, dia=24, n_bar=5, n_circle=24, cover=30,
conc_mat=concrete, steel_mat=steel
)
geometry.create_mesh(mesh_sizes=[500])
.. figure:: ../images/sections/concrete_tee_section_geometry.png
:align: center
:scale: 50 %
Concrete tee section geometry.
.. figure:: ../images/sections/concrete_tee_section_mesh.png
:align: center
:scale: 50 %
Mesh generated from the above geometry.
"""
if n_bar < 2:
raise ValueError("Please provide 2 or more steel reinforcing bars.")
geom = primitive_sections.rectangular_section(b=b,
d=d - d_f,
material=conc_mat)
flange = primitive_sections.rectangular_section(b=b_f,
d=d_f,
material=conc_mat)
geom += flange.align_center(align_to=geom).align_to(other=geom, on="top")
x_i = cover + dia / 2
spacing = (b - 2 * cover - dia) / (n_bar - 1)
for i in range(n_bar):
bar = primitive_sections.circular_section(d=dia,
n=n_circle,
material=steel_mat)
geom += bar.shift_section(x_offset=x_i + spacing * i,
y_offset=cover + dia / 2)
return geom