def _analyze_common_structural_geometry(step, geometry, mesh_sizes, N, Vx, Vy,
Mxx, Myy, Mzz):
mesh = geometry.create_mesh(mesh_sizes=[mesh_sizes])
section = CrossSection(geometry, mesh)
finite_elements_number = len(section.mesh_elements)
if finite_elements_number > MAX_FINITE_ELEMENTS_NUMBER:
return False, None, None, None, None, None, None, None, None, None, None
elif finite_elements_number < MAX_FINITE_ELEMENTS_NUMBER and step == 'checking':
return True, None, None, None, None, None, None, None, None, None, None
else:
section.calculate_geometric_properties()
section.calculate_warping_properties()
loadcase = section.calculate_stress(N=N,
Vx=Vx,
Vy=Vy,
Mxx=Mxx,
Myy=Myy,
Mzz=Mzz)
nodes = section.mesh_nodes
stresses = loadcase.get_stress()[0]
area = section.get_area()
ixx_c, iyy_c, ixy_c = section.get_ic()
torsion_constant = section.get_j()
warping_constant = section.get_gamma()
elastic_centroid = section.get_c()
centroidal_shear_center = section.get_sc()
return True, nodes, stresses, area, ixx_c, iyy_c, ixy_c, torsion_constant, warping_constant, \
elastic_centroid, centroidal_shear_center
mesh = geometry.create_mesh(mesh_sizes=[5, 20])
# create a CrossSection object - take care to list the materials in the same order as entered into
# the MergedSection
section = CrossSection(geometry, mesh, materials=[steel, timber])
section.display_mesh_info() # display the mesh information
# plot the mesh with coloured materials and a line transparency of 0.5
section.plot_mesh(materials=True, alpha=0.5)
# perform a geometric, warping and plastic analysis
section.calculate_geometric_properties(time_info=True)
section.calculate_warping_properties(time_info=True)
section.calculate_plastic_properties(time_info=True, verbose=True)
# perform a stress analysis with N = 100 kN, Mxx = 120 kN.m and Vy = 75 kN
stress_post = section.calculate_stress(N=-100e3,
Mxx=-120e6,
Vy=-75e3,
time_info=True)
# print the results to the terminal
section.display_results()
# plot the centroids
section.plot_centroids()
stress_post.plot_stress_n_zz(pause=False) # plot the axial stress
stress_post.plot_stress_m_zz(pause=False) # plot the bending stress
stress_post.plot_stress_v_zxy() # plot the shear stress
def process_geometry(geometry, mesh_sizes, loadcases):
# update this to receive the geometry, mesh info, material and loads
# generate a finite element mesh
mesh = geometry.create_mesh(mesh_sizes=mesh_sizes)
# generate material - can be overwritten if needed --all in N and cm
# create a CrossSection object for analysis
section = CrossSection(geometry, mesh)
# calculate various cross-section properties
section.calculate_geometric_properties()
section.calculate_warping_properties()
section.calculate_plastic_properties()
# Area
area = section.get_area()
sheararea = section.get_As()
asx = sheararea[0]
asy = sheararea[1]
# Second Moment of Area about centroid
(ixx, iyy, ixy) = section.get_ic()
# Centroid
(xg, yg) = section.get_c()
# Radii of Gyration
(rxx, ryy) = section.get_rc()
# Principal bending axis angle
phi = section.get_phi()
# St. Venant torsion constant
ipp = section.get_j()
# Warping Constant
cw = section.get_gamma()
# Elastic Section Moduli
(welx_top, welx_bottom, wely_top, wely_bottom) = section.get_z()
# Plastic Section Moduli
(wplx, wply) = section.get_s()
# plot centroid to image
section.plot_centroids(pause=False)
buf = io.BytesIO()
plt.savefig(buf, format='png', bbox_inches='tight')
buf.seek(0)
plot_centroid = base64.b64encode(buf.getvalue()).decode()
plt.close()
# calculate torsion resistance from stress and torque
#from the below can also return torsional stress if wanted
stress_post = section.calculate_stress(Mzz=10)
unit_mzz_zxy = []
maxstress = []
for group in stress_post.material_groups:
maxstress.append(max(group.stress_result.sig_zxy_mzz))
unit_mzz_zxy.append(group.stress_result.sig_zxy_mzz.tolist())
#there should be only one maxstress value therefore:
wt = 10 / maxstress[0]
#plot this image
stress_post.plot_stress_mzz_zxy(pause=False)
buf = io.BytesIO()
plt.savefig(buf, format='png', bbox_inches='tight')
buf.seek(0)
plot_unittorsionstress = base64.b64encode(buf.getvalue()).decode()
plt.close()
#foreach load case submitted calculate vm stress state and create image
vmStressImages = {}
vmStressStates = {}
for loadcase in loadcases:
lc_name = loadcase[0]
s_n = loadcase[1]
s_vx = loadcase[2]
s_vy = loadcase[3]
s_mxx = loadcase[4]
s_myy = loadcase[5]
s_mzz = loadcase[6]
stress_post = section.calculate_stress(N=s_n,
Vx=s_vx,
Vy=s_vy,
Mxx=s_mxx,
Myy=s_myy,
Mzz=s_mzz)
stress_state = []
for group in stress_post.material_groups:
stress_state.append(group.stress_result.sig_vm.tolist())
vmStressStates['lc_' + str(lc_name) + '_vm_stress'] = stress_state
#plot this image
stress_post.plot_stress_vm(pause=False)
buf = io.BytesIO()
plt.savefig(buf, format='png', bbox_inches='tight')
buf.seek(0)
vmStressImages['lc_' + str(lc_name) + '_vm_stress'] = base64.b64encode(
buf.getvalue()).decode()
plt.close()
# create rhino mesh
rmesh = rhino_mesh_from_meshpy(mesh)
# return send_file(path, as_attachment=True)
# get some of the calculated section properties
return_data = {}
return_data['properties'] = {
'area': area,
'Avx': asx,
'Avy': asy,
'xg': xg,
'yg': yg,
'rxx': rxx,
'ryy': ryy,
'phi': phi,
'ixx': ixx,
'iyy': iyy,
'ipp': ipp,
'cw': cw,
'welx+': welx_top,
'welx-': welx_bottom,
'wely+': wely_top,
'wely-': wely_bottom,
'wplx': wplx,
'wply': wply,
'wt': wt,
}
return_data['geometry'] = {
'mesh': rhino.CommonObject.Encode(rmesh),
}
return_data['images'] = {
'centroids': plot_centroid,
'unittorsion_vxy_stress': plot_unittorsionstress,
}
return_data['images'].update(vmStressImages)
return_data['stress_results'] = {
'unittorsion_vxy_stress': unit_mzz_zxy,
}
return_data['stress_results'].update(vmStressStates)
return return_data
import sectionproperties.pre.sections as sections from sectionproperties.analysis.cross_section import CrossSection # create a 150x100x6 RHS on its side geometry = sections.Rhs(d=100, b=150, t=6, r_out=15, n_r=8) # create a mesh with a maximum area of 2 mesh = geometry.create_mesh(mesh_sizes=[2]) # create a CrossSection object section = CrossSection(geometry, mesh) # perform a geometry and warping analysis section.calculate_geometric_properties() section.calculate_warping_properties() # perform a stress analysis with Mx = 5 kN.m; Vx = 10 kN and Mzz = 3 kN.m case1 = section.calculate_stress(Mxx=5e6, Vx=10e3, Mzz=3e6) # perform a stress analysis with My = 15 kN.m; Vy = 30 kN and Mzz = 1.5 kN.m case2 = section.calculate_stress(Myy=15e6, Vy=30e3, Mzz=1.5e6) case1.plot_stress_m_zz(pause=False) # plot the bending stress for case1 case1.plot_vector_mzz_zxy(pause=False) # plot the torsion vectors for case1 case2.plot_stress_v_zxy(pause=False) # plot the shear stress for case1 case1.plot_stress_vm(pause=False) # plot the von mises stress for case1 case2.plot_stress_vm() # plot the von mises stress for case2
class OneSec:
"""表示一个截面"""
def __init__(self, pls):
"""
单独截面
:param pls: 多条 cad 多段线对象组成的列表，其中应有一根指示控制点的线
"""
# 原始线和控制点
self.pls_origin = []
self.points = []
for i in pls:
if i.area == 0:
self.points = i.id
else:
self.pls_origin.append(i)
# 对线段进行排序，得到分离节点和完整节点
self.areas = np.array([i.area for i in self.pls_origin])
self.pls = np.array(self.pls_origin)[np.argsort(self.areas)][::-1]
self.ids_sep = [i.id for i in self.pls]
self.ids = [j.tolist() for i in self.ids_sep for j in i]
# 获取节点连接方式
self.faces = []
id_num = 0
for i in self.ids_sep:
id_num_0 = id_num
for j in i:
connect = [
id_num, id_num_0
] if id_num + 1 == id_num_0 + len(i) else [id_num, id_num + 1]
self.faces.append(connect)
id_num += 1
# 定义其他所需值
self.geo = 0
self.mesh = 0
self.sec = 0
self.prop = {}
self.stress = 0
self.corner = []
self.ids_to_c = []
def sec_cal(self, mesh=0.01, d=0.03):
"""
对单个截面进行属性计算
:param mesh: 截面划分单元尺寸
:param d: 截取形心附近应力范围
:return: 无
"""
self.geo = sections.CustomSection(self.ids, self.faces,
self.points[1:], [self.points[0]])
self.mesh = self.geo.create_mesh(mesh_sizes=[mesh])
self.sec = CrossSection(self.geo, self.mesh)
self.sec.plot_mesh()
self.sec.calculate_geometric_properties()
self.sec.calculate_warping_properties()
# 获取截面属性
prop = self.sec.section_props
self.prop['center'] = self.sec.get_c()
self.ids_to_c = [i - self.prop['center'] for i in self.ids_sep]
self.prop['area'] = prop.area
self.prop['as'] = [prop.A_s22, prop.A_s11]
self.prop['i'] = [prop.j, prop.ixx_c, prop.iyy_c]
pts = np.array(self.ids)
left = prop.cx - pts[:, 0].min()
right = pts[:, 0].max() - prop.cx
top = pts[:, 1].max() - prop.cy
bot = prop.cy - pts[:, 1].min()
self.prop['c'] = [right, left, top, bot]
self.stress = self.sec.calculate_stress(Vx=1, Vy=1)
stresses = self.stress.get_stress()
dy = self.sec.get_c()[1] - self.sec.mesh_nodes[:, 1]
dx = self.sec.get_c()[0] - self.sec.mesh_nodes[:, 0]
qyb = stresses[0]['sig_zy_vy'][dx < d].max() * prop.ixx_c
qzb = stresses[0]['sig_zx_vx'][dy < d].max() * prop.iyy_c
self.prop['q'] = [qyb, qzb]
self.prop['p'] = [
self.pls[0].length,
sum([i.length for i in self.pls[1:]])
]
# 获取角点
pt_all = self.ids_to_c[0]
pt_1 = pt_all[(pt_all[:, 0] < 0) & (pt_all[:, 1] > 0)]
pt_2 = pt_all[(pt_all[:, 0] > 0) & (pt_all[:, 1] > 0)]
pt_3 = pt_all[(pt_all[:, 0] < 0) & (pt_all[:, 1] < 0)]
pt_4 = pt_all[(pt_all[:, 0] > 0) & (pt_all[:, 1] < 0)]
pt_1 = find_pt(pt_1, relation='max')
pt_2 = find_pt(pt_2, relation='max')
pt_3 = find_pt(pt_3, relation='max')
pt_4 = find_pt(pt_4, relation='max')
self.corner = [pt_1, pt_2, pt_4, pt_3]
