""" Provide the ``Olson 90`` class.
"""
# -- Imports -----------------------------------------------------------------
from .capacity_base import CapacityMethod
# -- Olson 90 Class ----------------------------------------------------------
[docs]class Olson90(CapacityMethod):
""" Class to represent the Olson 90 method for capacity calculations of
driven or drilled piles. For the engineering background refer to the section
on the :ref:`olson90-method`.
"""
# -- Constructor ---------------------------------------------------------
[docs] def __init__(self, project):
"""
Args:
project (class): Provide the ``Project`` object as defined in the
:class:`~edafos.project.Project` class.
"""
super().__init__(project=project)
self.method_name = 'Olson 90'
# Run pre check
self._pre_check(['soil_desc', 'tuw', 'corr_n', 'su'])
# Run analysis
self.run()
# -- Method for shaft resistance -----------------------------------------
[docs] def shaft_res_per_z(self, z1, z2):
""" Method that follows the Olson 90 method for pile shaft resistance
and calculates :math:`R_s` for a section defined by ``z1`` and ``z2``.
Args:
z1 (float): Vertical depth to the highest point of interest,
measured from the top of the soil profile.
- For **SI**: Enter depth, *z1*, in **meters**.
- For **English**: Enter depth, *z1*, in **feet**.
z2 (float): Vertical depth to the lowest point of interest,
measured from the top of the soil profile.
- For **SI**: Enter depth, *z1*, in **meters**.
- For **English**: Enter depth, *z1*, in **feet**.
Returns:
Quantity: Two values with units depending on pile type. The first
for **plugged** conditions, the second for **unplugged** conditions.
"""
# Input check
if z2 <= z1:
raise ValueError("'z2' must be larger than 'z1', please correct.")
# Get soil type (cohesive/cohesionless)
soil_type = self.project.sp.get_soil_prop(z2, 'soil_type')
# Get Average Effective Stress
mid_z = z1 + ((z2 - z1) / 2)
eff_stress = self.project.sp.calculate_stress(mid_z)
# -- Cohesive Soils --------------------------------------------------
if soil_type == 'cohesive':
# Get the shear strength
su = self.project.sp.get_soil_prop(z2, 'su')
# Get the alpha factor
a_factor = self.a_factor_rev_api(eff_stress, su)
# Calculate unit shaft resistance
f_s = self.unit_shaft_res_clay(a_factor, su)
pass
# -- Method that follows the recipe --------------------------------------
[docs] def run(self):
""" Method where the method "recipe" is compiled and all calculations
are performed.
Returns:
"""
# z_list = self._z_for_analysis()
z_list = self.project.z_layer_pile()
plugged = True
total_r_s_out = 0
total_r_s_in = 0
for top_z, bot_z in zip(z_list[:-1], z_list[1:]):
# Effective stress
mid_z = top_z + ((bot_z - top_z)/2)
eff_sigma = self.project.sp.calculate_stress(mid_z)
bot_sigma = self.project.sp.calculate_stress(bot_z)
# Get soil type (cohesive/cohesionless)
soil_type = self.project.sp.get_soil_prop(bot_z, 'soil_type')
# Plugged conditions
side_area_out = self.project.pile.side_area(top_z, bot_z,
box_area=True)
toe_area_pl = self.project.pile.xsection_area(bot_z, box_area=True,
soil_plug=True)
# Unplugged conditions
if self.project.pile.pile_type in ['pipe-open', 'h-pile']:
side_area_in = self.project.pile.side_area(top_z, bot_z,
inside=True)
toe_area_upl = self.project.pile.xsection_area(bot_z)
else:
side_area_in = 0 * self.project.set_units('pile_side_area')
toe_area_upl = 0 * self.project.set_units('pile_xarea_alt')
if soil_type == 'cohesive':
# Side Friction
su = self.project.sp.get_soil_prop(bot_z, 'su')
a_factor = self.a_factor_rev_api(eff_sigma, su)
f_s = self.unit_shaft_res_clay(a_factor, su)
# End bearing
toe_su = self.average_toe_su()
q_p = self.unit_toe_res_clay(toe_su)
else:
# Side Friction
corr_n = self.project.sp.get_soil_prop(bot_z, 'corr_n')
soil_desc = self.project.sp.get_soil_prop(bot_z, 'soil_desc')
if self.project.pile.pile_type in ['pipe-open', 'h-pile']:
k = self.lateral_k_olson90(corr_n, False)
else:
k = self.lateral_k_olson90(corr_n, True)
delta = self.olson90_table(soil_desc, corr_n, 'delta')
f_lim = self.olson90_table(soil_desc, corr_n, 'f_lim')
f_s = min(self.unit_shaft_res_sand(k, eff_sigma, delta), f_lim)
# End bearing
n_q = self.olson90_table(soil_desc, corr_n, 'N_q')
q_lim = self.olson90_table(soil_desc, corr_n, 'q_lim')
q_p = min((bot_sigma * n_q), q_lim)
r_s_out = self.shaft_resistance(f_s, side_area_out)
r_s_in = self.shaft_resistance(f_s, side_area_in)
total_r_s_out = total_r_s_out + r_s_out
total_r_s_in = total_r_s_in + r_s_in
r_p_pl = self.toe_resistance(q_p, toe_area_pl)
r_p_upl = self.toe_resistance(q_p, toe_area_upl)
# Plugged total resistance
r_n_pl = total_r_s_out + r_p_pl
# Unplugged total resistance
if self.project.pile.pile_type in ['pipe-open', 'h-pile']:
r_n_upl = total_r_s_out + total_r_s_in + r_p_upl
else:
r_n_upl = 0 + total_r_s_in + r_p_upl
# Store values in data frame
self.tab_results.loc[len(self.tab_results) + 1] = [
bot_z, total_r_s_out.magnitude, total_r_s_in.magnitude,
r_p_pl.magnitude, r_p_upl.magnitude, r_n_pl.magnitude,
r_n_upl.magnitude]
max_unplugged = self.tab_results.iloc[:, -1].max()
max_pluged = self.tab_results.iloc[:, -2].max()
if self.project.pile.pile_type in ['pipe-open', 'h-pile']:
if max_unplugged < max_pluged:
plugged = False
result = min(max_unplugged, max_pluged)
else:
result = max_pluged
self.capacity = result
self.plugged = plugged
return self
