def calc_vert_strip_via_gazetas_1991(sl,
fd,
ip_axis='width',
a0=0.0,
f_contact=1.0,
h_rigid=None,
**kwargs):
"""
Vertical stiffness per metre of a footing with infinite out-of-plane length
Parameters
----------
sl: Soil Object
fd: Foundation object
a0: float
Dynamic factor
f_contact: float
Effective sidewall contact scaling factor
f_contact
h_rigid
kwargs
Returns
-------
"""
l_ip = getattr(fd, ip_axis)
b = l_ip / 2
v = sl.poissons_ratio
k_strip = 0.73 * sl.g_mod / (1 - v)
if a0:
lob = 1000
if sl.poissons_ratio <= 0.4:
f_dyn_surf = tdc.get_kz_gazetas_v_lte_0p4(a0, lob)
else:
f_dyn_surf = tdc.get_kz_gazetas_v_gt_0p4(a0, lob)
else:
f_dyn_surf = 1.
if fd.depth is not None and fd.depth != 0.0:
if fd.depth < 0.0:
raise ValueError(
f'foundation depth must be zero or greater, not {fd.depth}')
if f_contact == 0.0:
dw = 0.0
else:
dw = min([fd.height, fd.depth]) * f_contact
a_w = 2 * dw * fd.width
n_emb = (1 + fd.depth / (21 * b)) * (1 + 0.2 * (a_w /
(2 * b))**(2. / 3))
if v <= 0.4:
f_dyn_full_emb = 1 - 0.09 * (fd.depth / b)**(3. / 4) * a0**2
f_dyn_trench = 1 + 0.09 * (fd.depth / b)**(3. / 4) * a0**2
else:
f_dyn_full_emb = 1 - 0.35 * (fd.depth / b)**0.5 * a0**3.5
f_dyn_trench = f_dyn_surf # Assume the same as the surface - this is currently not provided
f_dyn_surf = 1.
# interpolate between
f_dyn_emb = f_dyn_trench + (f_dyn_full_emb - f_dyn_trench) * (dw /
fd.depth)
else:
n_emb = 1
f_dyn_emb = 1.0
if h_rigid:
n_rigid = 1 + 3.5 * b / h_rigid
else:
n_rigid = 1
return k_strip * n_emb * f_dyn_surf * f_dyn_emb * n_rigid
def calc_vert_via_gazetas_1991(sl, fd, a0=None, f_contact=1.0):
"""
Vertical stiffness of foundation
Parameters
----------
sl: Soil Object
fd: Foundation object
a0: float
Dynamic factor
f_contact: float
Effective sidewall contact scaling factor
Returns
-------
"""
v = sl.poissons_ratio
l = fd.length * 0.5
b = fd.width * 0.5
k_v_0 = 2 * sl.g_mod * l / (1 - v) * (0.73 + 1.54 * (b / l)**0.75)
if a0:
if sl.poissons_ratio <= 0.4:
f_dyn_surf = tdc.get_kz_gazetas_v_lte_0p4(a0, l / b)
else:
f_dyn_surf = tdc.get_kz_gazetas_v_gt_0p4(a0, l / b)
else:
f_dyn_surf = 1.
if fd.depth is not None and fd.depth != 0.0:
if fd.depth < 0.0:
raise ValueError(
f'foundation depth must be zero or greater, not {fd.depth}')
if f_contact == 0.0:
dw = 0.0
else:
dw = min([fd.height, fd.depth]) * f_contact
a_w = 2 * dw * (fd.width + fd.length)
chi = b / l
n_emb = (1 + fd.depth / (21 * b) *
(1 + 1.3 * chi)) * (1 + 0.2 * (a_w / (4 * b * l))**(2. / 3))
if a0:
h = min([fd.height, fd.depth])
if v <= 0.4:
f_dyn_full_emb = 1 - 0.09 * (fd.depth / b)**(3. / 4) * a0**2
f_dyn_trench = 1 + 0.09 * (fd.depth / b)**(3. / 4) * a0**2
else:
if l / b < 2.5:
f_dyn_full_emb = 1 - 0.09 * (fd.depth / b)**(3. /
4) * a0**2
else:
f_dyn_full_emb = 1 - 0.35 * (fd.depth / b)**0.5 * a0**3.5
f_dyn_trench = f_dyn_surf # Assume the same as the surface - this is currently not provided
f_dyn_surf = 1.
# interpolate between
f_dyn_emb = f_dyn_trench + (f_dyn_full_emb - f_dyn_trench) * (
(h * f_contact) / fd.depth)
else:
f_dyn_emb = 1
else:
n_emb = 1.0
f_dyn_emb = 1.0
return k_v_0 * n_emb * f_dyn_surf * f_dyn_emb
