STEP 1: Extracted Data

{'project_info': {'boring_number': '1', 'location': 'Marshalltown, Iowa', 'date': '9-1-10', 'ground_surface_elevation': 936.5}, 'groundwater_depth': 10.0, 'soil_layers': [{'depth_from': 0.0, 'depth_to': 5.0, 'elevation_from': 936.5, 'elevation_to': 931.5, 'soil_type': 'Lean Clay', 'description': 'FILL: LEAN CLAY, Trace Sand and Gravel, Brown and Dark Brown', 'unit_weight': 120.0, 'spt_n_field': 14, 'sigma_v': 600.0, 'sigma_v_prime': 600.0, 'n60': 14.0, 'cn': None, 'n1_60': None, 'phi_prime': None, 'cohesion': 3500.0, 'moisture_content': None}, {'depth_from': 5.0, 'depth_to': 10.0, 'elevation_from': 931.5, 'elevation_to': 926.5, 'soil_type': 'Lean Clay', 'description': 'LEAN CLAY, Trace Sand, Brown, Medium Stiff', 'unit_weight': 120.0, 'spt_n_field': 15, 'sigma_v': 1200.0, 'sigma_v_prime': 876.0, 'n60': 15.0, 'cn': None, 'n1_60': None, 'phi_prime': None, 'cohesion': 3750.0, 'moisture_content': None}, {'depth_from': 10.0, 'depth_to': 15.0, 'elevation_from': 926.5, 'elevation_to': 921.5, 'soil_type': 'Fine to Medium Sand', 'description': 'FINE TO MEDIUM SAND, Trace Clay, Brown, Medium Dense', 'unit_weight': 125.0, 'spt_n_field': 18, 'sigma_v': 1872.0, 'sigma_v_prime': 1248.0, 'n60': 18.0, 'cn': 1.3, 'n1_60': 23.4, 'phi_prime': 38.5, 'cohesion': None, 'moisture_content': None}, {'depth_from': 15.0, 'depth_to': 22.0, 'elevation_from': 921.5, 'elevation_to': 914.5, 'soil_type': 'Sandy Lean Clay', 'description': 'SANDY LEAN CLAY, Trace Gravel, Brown, Stiff, Occasional Sand Seams and Cobbles', 'unit_weight': 120.0, 'spt_n_field': 18, 'sigma_v': 2640.0, 'sigma_v_prime': 2016.0, 'n60': 18.0, 'cn': None, 'n1_60': None, 'phi_prime': None, 'cohesion': 4500.0, 'moisture_content': None}, {'depth_from': 22.0, 'depth_to': 34.0, 'elevation_from': 914.5, 'elevation_to': 902.5, 'soil_type': 'Sandy Lean Clay', 'description': 'SANDY LEAN CLAY, Trace Gravel, Dark Gray, Very Stiff to Hard, Occasional Sand Seams and Cobbles', 'unit_weight': 120.0, 'spt_n_field': 18, 'sigma_v': 4080.0, 'sigma_v_prime': 3456.0, 'n60': 18.0, 'cn': None, 'n1_60': None, 'phi_prime': None, 'cohesion': 4500.0, 'moisture_content': None}], 'design_summary': [{'layer_description': 'FINE TO MEDIUM SAND (10-15 ft)', 'parameter_type': 'phi_prime', 'recommended_value': 38.5, 'unit': 'degrees', 'range': '36-40 degrees'}, {'layer_description': 'SANDY LEAN CLAY (15-34 ft)', 'parameter_type': 'cohesion', 'recommended_value': 4500.0, 'unit': 'psf', 'range': '4000-5000 psf'}], 'plot_data': {'depths': [0, 5, 10, 15, 22, 34], 'phi_prime_values': [None, None, 38.5, None, None, None], 'cohesion_values': [3500, 3750, None, 4500, 4500, None]}, 'notes': 'The boring log indicates varying stiffness in clay layers and medium dense sand. Groundwater table assumed at 10 ft depth.', 'designs': [{'timestamp': '2025-12-26T07:53:32.466579+00:00', 'design_load': 20.0, 'safety_factor': 2.0, 'shaft_system': None, 'use_ai': True, 'result': {'design_load': 20.0, 'safety_factor': 2.0, 'required_ultimate_capacity': 40.0, 'ai_recommendations': {'recommended_min_depth': 22.0, 'recommended_max_depth': 34.0, 'recommended_shaft_systems': ['SS150', 'SS175'], 'depth_rationale': 'The recommended depth range ensures engagement with the dense sand layer and stiff clay for optimal bearing capacity.', 'shaft_rationale': 'SS150 and SS175 systems meet the ultimate capacity requirements and provide flexibility in torque and load handling.', 'bearing_layer_analysis': 'Key bearing layers are the dense sand (Layer 3) and stiff clay (Layer 5) with high cohesion and friction angle.', 'design_alternatives': [{'name': 'Option 1: SS175 Triple Helix 12"-14"-14"', 'shaft_system': 'SS175', 'helix_configuration': [{'diameter': 12, 'depth': 22.0, 'soil_layer': 'Fine to Medium Sand'}, {'diameter': 14, 'depth': 25.5, 'soil_layer': 'Sandy Lean Clay'}, {'diameter': 14, 'depth': 29.0, 'soil_layer': 'Sandy Lean Clay'}], 'estimated_depth': 29.0, 'minimum_torque': 10000, 'torque_correlation_factor': 10, 'priority': 1, 'rationale': 'Meets 100-kip ultimate capacity requirement. Helices engage dense sand and stiff clay layers. Design controlled by SS175 mechanical limit.', 'advantages': ['Meets exact load requirement', 'Engages strongest soil layers', 'Adequate torque capacity'], 'considerations': ['Requires 10,000 ft-lb installation torque', 'Deeper installation (29 ft)'], 'failure_analysis': 'Would fail if installation torque cannot reach 10,000 ft-lb or if dense sand layer is not encountered at expected depth', 'installation_specs': {'min_torque_ftlb': 10000, 'embedment_depth_ft': 29.0, 'termination_criteria': 'Achieve both 29 ft depth AND 10,000 ft-lb torque', 'buckling_check': 'N > 10 in bearing strata - adequate'}}, {'name': 'Option 2: SS150 Double Helix 10"-12"', 'shaft_system': 'SS150', 'helix_configuration': [{'diameter': 10, 'depth': 18.0, 'soil_layer': 'Sandy Lean Clay'}, {'diameter': 12, 'depth': 22.0, 'soil_layer': 'Fine to Medium Sand'}], 'estimated_depth': 22.0, 'minimum_torque': 7000, 'torque_correlation_factor': 10, 'priority': 2, 'rationale': 'Economical option for moderate loads. Engages dense sand layer.', 'advantages': ['Lower cost', 'Shallower installation', 'Lower torque requirement'], 'considerations': ['May be capacity-limited', 'Less redundancy than triple helix'], 'failure_analysis': 'Would fail if soil conditions are weaker than anticipated or if only one helix engages bearing layer', 'installation_specs': {'min_torque_ftlb': 7000, 'embedment_depth_ft': 22.0, 'termination_criteria': 'Achieve both 22 ft depth AND 7,000 ft-lb torque', 'buckling_check': 'N > 15 in bearing strata - adequate'}}, {'name': 'Option 3: SS175 Double Helix 12"-14"', 'shaft_system': 'SS175', 'helix_configuration': [{'diameter': 12, 'depth': 20.0, 'soil_layer': 'Sandy Lean Clay'}, {'diameter': 14, 'depth': 24.0, 'soil_layer': 'Fine to Medium Sand'}], 'estimated_depth': 24.0, 'minimum_torque': 10000, 'torque_correlation_factor': 10, 'priority': 3, 'rationale': 'Provides higher capacity with fewer helices, engaging strong sand layer.', 'advantages': ['Higher capacity with fewer helices', 'Engages strong sand layer'], 'considerations': ['Higher torque requirement', 'Potentially deeper installation'], 'failure_analysis': 'Would fail if installation torque cannot reach required value due to hard layer', 'installation_specs': {'min_torque_ftlb': 10000, 'embedment_depth_ft': 24.0, 'termination_criteria': 'Achieve both 24 ft depth AND 10,000 ft-lb torque', 'buckling_check': 'N > 10 in bearing strata - adequate'}}], 'soil_analysis': 'The soil stratigraphy consists of alternating layers of clay and sand, with the dense sand layer at 10-15 ft providing high bearing capacity due to its friction angle.', 'recommendations_summary': 'The SS175 system with a triple helix configuration is recommended for maximum capacity, while the SS150 double helix offers a more economical solution. Both designs engage the strongest soil layers and meet the required capacity.'}, 'design_parameters': {'min_depth': 22.0, 'max_depth': 34.0, 'shaft_system': 'SS150'}, 'calculated_designs': [{'name': 'Option 1: SS175 Triple Helix 12"-14"-14"', 'shaft_system': 'SS175', 'helix_configuration': [{'diameter': 12, 'depth': 22.0, 'soil_layer': 'Fine to Medium Sand'}, {'diameter': 14, 'depth': 25.5, 'soil_layer': 'Sandy Lean Clay'}, {'diameter': 14, 'depth': 29.0, 'soil_layer': 'Sandy Lean Clay'}], 'ultimate_capacity': 129.6459375, 'allowable_capacity': 64.82296875, 'design_load': 20.0, 'safety_factor': 2.0, 'passes': True, 'capacity_ratio': 3.2411484375, 'priority': 1, 'rationale': 'Meets 100-kip ultimate capacity requirement. Helices engage dense sand and stiff clay layers. Design controlled by SS175 mechanical limit.', 'advantages': ['Meets exact load requirement', 'Engages strongest soil layers', 'Adequate torque capacity'], 'considerations': ['Requires 10,000 ft-lb installation torque', 'Deeper installation (29 ft)'], 'capacity_details': {'shaft_system': 'SS175', 'num_helices': 3, 'helix_details': [{'helix_diameter': 12, 'depth': 22.0, 'helix_area': 0.771, 'soil_type': 'Sandy Lean Clay', 'spt_n_value': 10, 'cohesion': 4.5, 'friction_angle': 0, 'overburden_pressure': 2.665, 'bearing_factor_nq': 1.5, 'bearing_capacity_per_unit_area': 44.4975, 'cohesion_component': 40.5, 'friction_component': 3.9975, 'capacity_soil': 34.3075725, 'capacity_mechanical': 100, 'capacity_ultimate': 34.3075725, 'controlling_factor': 'Soil', 'calculation_steps': [{'step': 1, 'description': 'Helix Area Lookup', 'formula': 'Ah = Area of 12" helix', 'calculation': 'Ah = 0.771 sq.ft', 'result': 0.771, 'units': 'sq.ft'}, {'step': 2, 'description': 'Soil Properties at Helix Depth', 'formula': 'At depth = 22.0 ft', 'calculation': 'Soil Type: Sandy Lean Clay\nSPT N-value: 10\nCohesion (c): 4.50 ksf\nFriction Angle (φ): 0.0°', 'result': {'cohesion': 4.5, 'friction_angle': 0}, 'units': 'various'}, {'step': 3, 'description': 'Effective Overburden Pressure', 'formula': 'q = Σ(γ × thickness) for each layer', 'calculation': 'q = 2.665 ksf (at depth 22.0 ft)', 'result': 2.665, 'units': 'ksf'}, {'step': 4, 'description': 'Bearing Capacity Factor (Nq)', 'formula': 'Nq = f(φ = 0.0°)', 'calculation': 'Nq = 1.50 (interpolated from bearing capacity tables)', 'result': 1.5, 'units': 'dimensionless'}, {'step': 5, 'description': 'Bearing Capacity per Unit Area', 'formula': 'qult = Nc×c + q×Nq (where Nc = 9.0 for deep foundations)', 'calculation': 'qult = 9.0×4.50 + 2.665×1.50\nqult = 40.50 + 4.00\nqult = 44.50 ksf', 'result': 44.4975, 'units': 'ksf'}, {'step': 6, 'description': 'Total Soil Bearing Capacity', 'formula': 'Qh = Ah × qult', 'calculation': 'Qh = 0.771 × 44.50\nQh = 34.31 kips', 'result': 34.3075725, 'units': 'kips'}, {'step': 7, 'description': 'Mechanical Capacity Limit', 'formula': 'Qs = SS175 ultimate capacity', 'calculation': 'Qs = 100.00 kips', 'result': 100, 'units': 'kips'}, {'step': 8, 'description': 'Ultimate Capacity (Controlling)', 'formula': 'Qult = min(Qh, Qs)', 'calculation': 'Qult = min(34.31, 100.00)\nQult = 34.31 kips\nControlled by: Soil', 'result': 34.3075725, 'units': 'kips'}]}, {'helix_diameter': 14, 'depth': 25.5, 'helix_area': 1.049, 'soil_type': 'Sandy Lean Clay', 'spt_n_value': 10, 'cohesion': 4.5, 'friction_angle': 0, 'overburden_pressure': 3.085, 'bearing_factor_nq': 1.5, 'bearing_capacity_per_unit_area': 45.1275, 'cohesion_component': 40.5, 'friction_component': 4.6274999999999995, 'capacity_soil': 47.3387475, 'capacity_mechanical': 80.0, 'capacity_ultimate': 47.3387475, 'controlling_factor': 'Soil', 'calculation_steps': [{'step': 1, 'description': 'Helix Area Lookup', 'formula': 'Ah = Area of 14" helix', 'calculation': 'Ah = 1.049 sq.ft', 'result': 1.049, 'units': 'sq.ft'}, {'step': 2, 'description': 'Soil Properties at Helix Depth', 'formula': 'At depth = 25.5 ft', 'calculation': 'Soil Type: Sandy Lean Clay\nSPT N-value: 10\nCohesion (c): 4.50 ksf\nFriction Angle (φ): 0.0°', 'result': {'cohesion': 4.5, 'friction_angle': 0}, 'units': 'various'}, {'step': 3, 'description': 'Effective Overburden Pressure', 'formula': 'q = Σ(γ × thickness) for each layer', 'calculation': 'q = 3.085 ksf (at depth 25.5 ft)', 'result': 3.085, 'units': 'ksf'}, {'step': 4, 'description': 'Bearing Capacity Factor (Nq)', 'formula': 'Nq = f(φ = 0.0°)', 'calculation': 'Nq = 1.50 (interpolated from bearing capacity tables)', 'result': 1.5, 'units': 'dimensionless'}, {'step': 5, 'description': 'Bearing Capacity per Unit Area', 'formula': 'qult = Nc×c + q×Nq (where Nc = 9.0 for deep foundations)', 'calculation': 'qult = 9.0×4.50 + 3.085×1.50\nqult = 40.50 + 4.63\nqult = 45.13 ksf', 'result': 45.1275, 'units': 'ksf'}, {'step': 6, 'description': 'Total Soil Bearing Capacity', 'formula': 'Qh = Ah × qult', 'calculation': 'Qh = 1.049 × 45.13\nQh = 47.34 kips', 'result': 47.3387475, 'units': 'kips'}, {'step': 7, 'description': 'Mechanical Capacity Limit', 'formula': 'Qs = SS175 ultimate capacity × 0.8 (14" helix reduction)', 'calculation': 'Qs = 100.0 × 0.8\nQs = 80.00 kips', 'result': 80.0, 'units': 'kips'}, {'step': 8, 'description': 'Ultimate Capacity (Controlling)', 'formula': 'Qult = min(Qh, Qs)', 'calculation': 'Qult = min(47.34, 80.00)\nQult = 47.34 kips\nControlled by: Soil', 'result': 47.3387475, 'units': 'kips'}]}, {'helix_diameter': 14, 'depth': 29.0, 'helix_area': 1.049, 'soil_type': 'Sandy Lean Clay', 'spt_n_value': 10, 'cohesion': 4.5, 'friction_angle': 0, 'overburden_pressure': 3.505, 'bearing_factor_nq': 1.5, 'bearing_capacity_per_unit_area': 45.7575, 'cohesion_component': 40.5, 'friction_component': 5.2575, 'capacity_soil': 47.9996175, 'capacity_mechanical': 80.0, 'capacity_ultimate': 47.9996175, 'controlling_factor': 'Soil', 'calculation_steps': [{'step': 1, 'description': 'Helix Area Lookup', 'formula': 'Ah = Area of 14" helix', 'calculation': 'Ah = 1.049 sq.ft', 'result': 1.049, 'units': 'sq.ft'}, {'step': 2, 'description': 'Soil Properties at Helix Depth', 'formula': 'At depth = 29.0 ft', 'calculation': 'Soil Type: Sandy Lean Clay\nSPT N-value: 10\nCohesion (c): 4.50 ksf\nFriction Angle (φ): 0.0°', 'result': {'cohesion': 4.5, 'friction_angle': 0}, 'units': 'various'}, {'step': 3, 'description': 'Effective Overburden Pressure', 'formula': 'q = Σ(γ × thickness) for each layer', 'calculation': 'q = 3.505 ksf (at depth 29.0 ft)', 'result': 3.505, 'units': 'ksf'}, {'step': 4, 'description': 'Bearing Capacity Factor (Nq)', 'formula': 'Nq = f(φ = 0.0°)', 'calculation': 'Nq = 1.50 (interpolated from bearing capacity tables)', 'result': 1.5, 'units': 'dimensionless'}, {'step': 5, 'description': 'Bearing Capacity per Unit Area', 'formula': 'qult = Nc×c + q×Nq (where Nc = 9.0 for deep foundations)', 'calculation': 'qult = 9.0×4.50 + 3.505×1.50\nqult = 40.50 + 5.26\nqult = 45.76 ksf', 'result': 45.7575, 'units': 'ksf'}, {'step': 6, 'description': 'Total Soil Bearing Capacity', 'formula': 'Qh = Ah × qult', 'calculation': 'Qh = 1.049 × 45.76\nQh = 48.00 kips', 'result': 47.9996175, 'units': 'kips'}, {'step': 7, 'description': 'Mechanical Capacity Limit', 'formula': 'Qs = SS175 ultimate capacity × 0.8 (14" helix reduction)', 'calculation': 'Qs = 100.0 × 0.8\nQs = 80.00 kips', 'result': 80.0, 'units': 'kips'}, {'step': 8, 'description': 'Ultimate Capacity (Controlling)', 'formula': 'Qult = min(Qh, Qs)', 'calculation': 'Qult = min(48.00, 80.00)\nQult = 48.00 kips\nControlled by: Soil', 'result': 47.9996175, 'units': 'kips'}]}], 'total_ultimate_capacity': 129.6459375, 'calculation_method': 'Chance Individual Bearing Method'}, 'installation_specifications': {'torque_correlation_factor': 10, 'min_installation_torque_ftlb': 12964, 'max_torque_rating_ftlb': 10000, 'torque_adequate': False, 'embedment_depth_ft': 29.0, 'termination_criteria': 'Achieve both 29.0 ft depth AND 12,964 ft-lb torque', 'buckling_check': {'min_n_value': 10, 'adequate': True, 'note': 'Adequate (N > 4)'}}}, {'name': 'Option 2: SS150 Double Helix 10"-12"', 'shaft_system': 'SS150', 'helix_configuration': [{'diameter': 10, 'depth': 18.0, 'soil_layer': 'Sandy Lean Clay'}, {'diameter': 12, 'depth': 22.0, 'soil_layer': 'Fine to Medium Sand'}], 'ultimate_capacity': 57.553425000000004, 'allowable_capacity': 28.776712500000002, 'design_load': 20.0, 'safety_factor': 2.0, 'passes': True, 'capacity_ratio': 1.438835625, 'priority': 2, 'rationale': 'Economical option for moderate loads. Engages dense sand layer.', 'advantages': ['Lower cost', 'Shallower installation', 'Lower torque requirement'], 'considerations': ['May be capacity-limited', 'Less redundancy than triple helix'], 'capacity_details': {'shaft_system': 'SS150', 'num_helices': 2, 'helix_details': [{'helix_diameter': 10, 'depth': 18.0, 'helix_area': 0.531, 'soil_type': 'Sandy Lean Clay', 'spt_n_value': 10, 'cohesion': 4.5, 'friction_angle': 0, 'overburden_pressure': 2.185, 'bearing_factor_nq': 1.5, 'bearing_capacity_per_unit_area': 43.7775, 'cohesion_component': 40.5, 'friction_component': 3.2775, 'capacity_soil': 23.2458525, 'capacity_mechanical': 70, 'capacity_ultimate': 23.2458525, 'controlling_factor': 'Soil', 'calculation_steps': [{'step': 1, 'description': 'Helix Area Lookup', 'formula': 'Ah = Area of 10" helix', 'calculation': 'Ah = 0.531 sq.ft', 'result': 0.531, 'units': 'sq.ft'}, {'step': 2, 'description': 'Soil Properties at Helix Depth', 'formula': 'At depth = 18.0 ft', 'calculation': 'Soil Type: Sandy Lean Clay\nSPT N-value: 10\nCohesion (c): 4.50 ksf\nFriction Angle (φ): 0.0°', 'result': {'cohesion': 4.5, 'friction_angle': 0}, 'units': 'various'}, {'step': 3, 'description': 'Effective Overburden Pressure', 'formula': 'q = Σ(γ × thickness) for each layer', 'calculation': 'q = 2.185 ksf (at depth 18.0 ft)', 'result': 2.185, 'units': 'ksf'}, {'step': 4, 'description': 'Bearing Capacity Factor (Nq)', 'formula': 'Nq = f(φ = 0.0°)', 'calculation': 'Nq = 1.50 (interpolated from bearing capacity tables)', 'result': 1.5, 'units': 'dimensionless'}, {'step': 5, 'description': 'Bearing Capacity per Unit Area', 'formula': 'qult = Nc×c + q×Nq (where Nc = 9.0 for deep foundations)', 'calculation': 'qult = 9.0×4.50 + 2.185×1.50\nqult = 40.50 + 3.28\nqult = 43.78 ksf', 'result': 43.7775, 'units': 'ksf'}, {'step': 6, 'description': 'Total Soil Bearing Capacity', 'formula': 'Qh = Ah × qult', 'calculation': 'Qh = 0.531 × 43.78\nQh = 23.25 kips', 'result': 23.2458525, 'units': 'kips'}, {'step': 7, 'description': 'Mechanical Capacity Limit', 'formula': 'Qs = SS150 ultimate capacity', 'calculation': 'Qs = 70.00 kips', 'result': 70, 'units': 'kips'}, {'step': 8, 'description': 'Ultimate Capacity (Controlling)', 'formula': 'Qult = min(Qh, Qs)', 'calculation': 'Qult = min(23.25, 70.00)\nQult = 23.25 kips\nControlled by: Soil', 'result': 23.2458525, 'units': 'kips'}]}, {'helix_diameter': 12, 'depth': 22.0, 'helix_area': 0.771, 'soil_type': 'Sandy Lean Clay', 'spt_n_value': 10, 'cohesion': 4.5, 'friction_angle': 0, 'overburden_pressure': 2.665, 'bearing_factor_nq': 1.5, 'bearing_capacity_per_unit_area': 44.4975, 'cohesion_component': 40.5, 'friction_component': 3.9975, 'capacity_soil': 34.3075725, 'capacity_mechanical': 70, 'capacity_ultimate': 34.3075725, 'controlling_factor': 'Soil', 'calculation_steps': [{'step': 1, 'description': 'Helix Area Lookup', 'formula': 'Ah = Area of 12" helix', 'calculation': 'Ah = 0.771 sq.ft', 'result': 0.771, 'units': 'sq.ft'}, {'step': 2, 'description': 'Soil Properties at Helix Depth', 'formula': 'At depth = 22.0 ft', 'calculation': 'Soil Type: Sandy Lean Clay\nSPT N-value: 10\nCohesion (c): 4.50 ksf\nFriction Angle (φ): 0.0°', 'result': {'cohesion': 4.5, 'friction_angle': 0}, 'units': 'various'}, {'step': 3, 'description': 'Effective Overburden Pressure', 'formula': 'q = Σ(γ × thickness) for each layer', 'calculation': 'q = 2.665 ksf (at depth 22.0 ft)', 'result': 2.665, 'units': 'ksf'}, {'step': 4, 'description': 'Bearing Capacity Factor (Nq)', 'formula': 'Nq = f(φ = 0.0°)', 'calculation': 'Nq = 1.50 (interpolated from bearing capacity tables)', 'result': 1.5, 'units': 'dimensionless'}, {'step': 5, 'description': 'Bearing Capacity per Unit Area', 'formula': 'qult = Nc×c + q×Nq (where Nc = 9.0 for deep foundations)', 'calculation': 'qult = 9.0×4.50 + 2.665×1.50\nqult = 40.50 + 4.00\nqult = 44.50 ksf', 'result': 44.4975, 'units': 'ksf'}, {'step': 6, 'description': 'Total Soil Bearing Capacity', 'formula': 'Qh = Ah × qult', 'calculation': 'Qh = 0.771 × 44.50\nQh = 34.31 kips', 'result': 34.3075725, 'units': 'kips'}, {'step': 7, 'description': 'Mechanical Capacity Limit', 'formula': 'Qs = SS150 ultimate capacity', 'calculation': 'Qs = 70.00 kips', 'result': 70, 'units': 'kips'}, {'step': 8, 'description': 'Ultimate Capacity (Controlling)', 'formula': 'Qult = min(Qh, Qs)', 'calculation': 'Qult = min(34.31, 70.00)\nQult = 34.31 kips\nControlled by: Soil', 'result': 34.3075725, 'units': 'kips'}]}], 'total_ultimate_capacity': 57.553425000000004, 'calculation_method': 'Chance Individual Bearing Method'}, 'installation_specifications': {'torque_correlation_factor': 10, 'min_installation_torque_ftlb': 5755, 'max_torque_rating_ftlb': 7000, 'torque_adequate': True, 'embedment_depth_ft': 22.0, 'termination_criteria': 'Achieve both 22.0 ft depth AND 5,755 ft-lb torque', 'buckling_check': {'min_n_value': 10, 'adequate': True, 'note': 'Adequate (N > 4)'}}}, {'name': 'Option 3: SS175 Double Helix 12"-14"', 'shaft_system': 'SS175', 'helix_configuration': [{'diameter': 12, 'depth': 20.0, 'soil_layer': 'Sandy Lean Clay'}, {'diameter': 14, 'depth': 24.0, 'soil_layer': 'Fine to Medium Sand'}], 'ultimate_capacity': 81.08553, 'allowable_capacity': 40.542765, 'design_load': 20.0, 'safety_factor': 2.0, 'passes': True, 'capacity_ratio': 2.02713825, 'priority': 3, 'rationale': 'Provides higher capacity with fewer helices, engaging strong sand layer.', 'advantages': ['Higher capacity with fewer helices', 'Engages strong sand layer'], 'considerations': ['Higher torque requirement', 'Potentially deeper installation'], 'capacity_details': {'shaft_system': 'SS175', 'num_helices': 2, 'helix_details': [{'helix_diameter': 12, 'depth': 20.0, 'helix_area': 0.771, 'soil_type': 'Sandy Lean Clay', 'spt_n_value': 10, 'cohesion': 4.5, 'friction_angle': 0, 'overburden_pressure': 2.425, 'bearing_factor_nq': 1.5, 'bearing_capacity_per_unit_area': 44.1375, 'cohesion_component': 40.5, 'friction_component': 3.6374999999999997, 'capacity_soil': 34.030012500000005, 'capacity_mechanical': 100, 'capacity_ultimate': 34.030012500000005, 'controlling_factor': 'Soil', 'calculation_steps': [{'step': 1, 'description': 'Helix Area Lookup', 'formula': 'Ah = Area of 12" helix', 'calculation': 'Ah = 0.771 sq.ft', 'result': 0.771, 'units': 'sq.ft'}, {'step': 2, 'description': 'Soil Properties at Helix Depth', 'formula': 'At depth = 20.0 ft', 'calculation': 'Soil Type: Sandy Lean Clay\nSPT N-value: 10\nCohesion (c): 4.50 ksf\nFriction Angle (φ): 0.0°', 'result': {'cohesion': 4.5, 'friction_angle': 0}, 'units': 'various'}, {'step': 3, 'description': 'Effective Overburden Pressure', 'formula': 'q = Σ(γ × thickness) for each layer', 'calculation': 'q = 2.425 ksf (at depth 20.0 ft)', 'result': 2.425, 'units': 'ksf'}, {'step': 4, 'description': 'Bearing Capacity Factor (Nq)', 'formula': 'Nq = f(φ = 0.0°)', 'calculation': 'Nq = 1.50 (interpolated from bearing capacity tables)', 'result': 1.5, 'units': 'dimensionless'}, {'step': 5, 'description': 'Bearing Capacity per Unit Area', 'formula': 'qult = Nc×c + q×Nq (where Nc = 9.0 for deep foundations)', 'calculation': 'qult = 9.0×4.50 + 2.425×1.50\nqult = 40.50 + 3.64\nqult = 44.14 ksf', 'result': 44.1375, 'units': 'ksf'}, {'step': 6, 'description': 'Total Soil Bearing Capacity', 'formula': 'Qh = Ah × qult', 'calculation': 'Qh = 0.771 × 44.14\nQh = 34.03 kips', 'result': 34.030012500000005, 'units': 'kips'}, {'step': 7, 'description': 'Mechanical Capacity Limit', 'formula': 'Qs = SS175 ultimate capacity', 'calculation': 'Qs = 100.00 kips', 'result': 100, 'units': 'kips'}, {'step': 8, 'description': 'Ultimate Capacity (Controlling)', 'formula': 'Qult = min(Qh, Qs)', 'calculation': 'Qult = min(34.03, 100.00)\nQult = 34.03 kips\nControlled by: Soil', 'result': 34.030012500000005, 'units': 'kips'}]}, {'helix_diameter': 14, 'depth': 24.0, 'helix_area': 1.049, 'soil_type': 'Sandy Lean Clay', 'spt_n_value': 10, 'cohesion': 4.5, 'friction_angle': 0, 'overburden_pressure': 2.905, 'bearing_factor_nq': 1.5, 'bearing_capacity_per_unit_area': 44.8575, 'cohesion_component': 40.5, 'friction_component': 4.3575, 'capacity_soil': 47.0555175, 'capacity_mechanical': 80.0, 'capacity_ultimate': 47.0555175, 'controlling_factor': 'Soil', 'calculation_steps': [{'step': 1, 'description': 'Helix Area Lookup', 'formula': 'Ah = Area of 14" helix', 'calculation': 'Ah = 1.049 sq.ft', 'result': 1.049, 'units': 'sq.ft'}, {'step': 2, 'description': 'Soil Properties at Helix Depth', 'formula': 'At depth = 24.0 ft', 'calculation': 'Soil Type: Sandy Lean Clay\nSPT N-value: 10\nCohesion (c): 4.50 ksf\nFriction Angle (φ): 0.0°', 'result': {'cohesion': 4.5, 'friction_angle': 0}, 'units': 'various'}, {'step': 3, 'description': 'Effective Overburden Pressure', 'formula': 'q = Σ(γ × thickness) for each layer', 'calculation': 'q = 2.905 ksf (at depth 24.0 ft)', 'result': 2.905, 'units': 'ksf'}, {'step': 4, 'description': 'Bearing Capacity Factor (Nq)', 'formula': 'Nq = f(φ = 0.0°)', 'calculation': 'Nq = 1.50 (interpolated from bearing capacity tables)', 'result': 1.5, 'units': 'dimensionless'}, {'step': 5, 'description': 'Bearing Capacity per Unit Area', 'formula': 'qult = Nc×c + q×Nq (where Nc = 9.0 for deep foundations)', 'calculation': 'qult = 9.0×4.50 + 2.905×1.50\nqult = 40.50 + 4.36\nqult = 44.86 ksf', 'result': 44.8575, 'units': 'ksf'}, {'step': 6, 'description': 'Total Soil Bearing Capacity', 'formula': 'Qh = Ah × qult', 'calculation': 'Qh = 1.049 × 44.86\nQh = 47.06 kips', 'result': 47.0555175, 'units': 'kips'}, {'step': 7, 'description': 'Mechanical Capacity Limit', 'formula': 'Qs = SS175 ultimate capacity × 0.8 (14" helix reduction)', 'calculation': 'Qs = 100.0 × 0.8\nQs = 80.00 kips', 'result': 80.0, 'units': 'kips'}, {'step': 8, 'description': 'Ultimate Capacity (Controlling)', 'formula': 'Qult = min(Qh, Qs)', 'calculation': 'Qult = min(47.06, 80.00)\nQult = 47.06 kips\nControlled by: Soil', 'result': 47.0555175, 'units': 'kips'}]}], 'total_ultimate_capacity': 81.08553, 'calculation_method': 'Chance Individual Bearing Method'}, 'installation_specifications': {'torque_correlation_factor': 10, 'min_installation_torque_ftlb': 8108, 'max_torque_rating_ftlb': 10000, 'torque_adequate': True, 'embedment_depth_ft': 24.0, 'termination_criteria': 'Achieve both 24.0 ft depth AND 8,108 ft-lb torque', 'buckling_check': {'min_n_value': 10, 'adequate': True, 'note': 'Adequate (N > 4)'}}}], 'best_design': {'name': 'Option 1: SS175 Triple Helix 12"-14"-14"', 'shaft_system': 'SS175', 'helix_configuration': [{'diameter': 12, 'depth': 22.0, 'soil_layer': 'Fine to Medium Sand'}, {'diameter': 14, 'depth': 25.5, 'soil_layer': 'Sandy Lean Clay'}, {'diameter': 14, 'depth': 29.0, 'soil_layer': 'Sandy Lean Clay'}], 'ultimate_capacity': 129.6459375, 'allowable_capacity': 64.82296875, 'design_load': 20.0, 'safety_factor': 2.0, 'passes': True, 'capacity_ratio': 3.2411484375, 'priority': 1, 'rationale': 'Meets 100-kip ultimate capacity requirement. Helices engage dense sand and stiff clay layers. Design controlled by SS175 mechanical limit.', 'advantages': ['Meets exact load requirement', 'Engages strongest soil layers', 'Adequate torque capacity'], 'considerations': ['Requires 10,000 ft-lb installation torque', 'Deeper installation (29 ft)'], 'capacity_details': {'shaft_system': 'SS175', 'num_helices': 3, 'helix_details': [{'helix_diameter': 12, 'depth': 22.0, 'helix_area': 0.771, 'soil_type': 'Sandy Lean Clay', 'spt_n_value': 10, 'cohesion': 4.5, 'friction_angle': 0, 'overburden_pressure': 2.665, 'bearing_factor_nq': 1.5, 'bearing_capacity_per_unit_area': 44.4975, 'cohesion_component': 40.5, 'friction_component': 3.9975, 'capacity_soil': 34.3075725, 'capacity_mechanical': 100, 'capacity_ultimate': 34.3075725, 'controlling_factor': 'Soil', 'calculation_steps': [{'step': 1, 'description': 'Helix Area Lookup', 'formula': 'Ah = Area of 12" helix', 'calculation': 'Ah = 0.771 sq.ft', 'result': 0.771, 'units': 'sq.ft'}, {'step': 2, 'description': 'Soil Properties at Helix Depth', 'formula': 'At depth = 22.0 ft', 'calculation': 'Soil Type: Sandy Lean Clay\nSPT N-value: 10\nCohesion (c): 4.50 ksf\nFriction Angle (φ): 0.0°', 'result': {'cohesion': 4.5, 'friction_angle': 0}, 'units': 'various'}, {'step': 3, 'description': 'Effective Overburden Pressure', 'formula': 'q = Σ(γ × thickness) for each layer', 'calculation': 'q = 2.665 ksf (at depth 22.0 ft)', 'result': 2.665, 'units': 'ksf'}, {'step': 4, 'description': 'Bearing Capacity Factor (Nq)', 'formula': 'Nq = f(φ = 0.0°)', 'calculation': 'Nq = 1.50 (interpolated from bearing capacity tables)', 'result': 1.5, 'units': 'dimensionless'}, {'step': 5, 'description': 'Bearing Capacity per Unit Area', 'formula': 'qult = Nc×c + q×Nq (where Nc = 9.0 for deep foundations)', 'calculation': 'qult = 9.0×4.50 + 2.665×1.50\nqult = 40.50 + 4.00\nqult = 44.50 ksf', 'result': 44.4975, 'units': 'ksf'}, {'step': 6, 'description': 'Total Soil Bearing Capacity', 'formula': 'Qh = Ah × qult', 'calculation': 'Qh = 0.771 × 44.50\nQh = 34.31 kips', 'result': 34.3075725, 'units': 'kips'}, {'step': 7, 'description': 'Mechanical Capacity Limit', 'formula': 'Qs = SS175 ultimate capacity', 'calculation': 'Qs = 100.00 kips', 'result': 100, 'units': 'kips'}, {'step': 8, 'description': 'Ultimate Capacity (Controlling)', 'formula': 'Qult = min(Qh, Qs)', 'calculation': 'Qult = min(34.31, 100.00)\nQult = 34.31 kips\nControlled by: Soil', 'result': 34.3075725, 'units': 'kips'}]}, {'helix_diameter': 14, 'depth': 25.5, 'helix_area': 1.049, 'soil_type': 'Sandy Lean Clay', 'spt_n_value': 10, 'cohesion': 4.5, 'friction_angle': 0, 'overburden_pressure': 3.085, 'bearing_factor_nq': 1.5, 'bearing_capacity_per_unit_area': 45.1275, 'cohesion_component': 40.5, 'friction_component': 4.6274999999999995, 'capacity_soil': 47.3387475, 'capacity_mechanical': 80.0, 'capacity_ultimate': 47.3387475, 'controlling_factor': 'Soil', 'calculation_steps': [{'step': 1, 'description': 'Helix Area Lookup', 'formula': 'Ah = Area of 14" helix', 'calculation': 'Ah = 1.049 sq.ft', 'result': 1.049, 'units': 'sq.ft'}, {'step': 2, 'description': 'Soil Properties at Helix Depth', 'formula': 'At depth = 25.5 ft', 'calculation': 'Soil Type: Sandy Lean Clay\nSPT N-value: 10\nCohesion (c): 4.50 ksf\nFriction Angle (φ): 0.0°', 'result': {'cohesion': 4.5, 'friction_angle': 0}, 'units': 'various'}, {'step': 3, 'description': 'Effective Overburden Pressure', 'formula': 'q = Σ(γ × thickness) for each layer', 'calculation': 'q = 3.085 ksf (at depth 25.5 ft)', 'result': 3.085, 'units': 'ksf'}, {'step': 4, 'description': 'Bearing Capacity Factor (Nq)', 'formula': 'Nq = f(φ = 0.0°)', 'calculation': 'Nq = 1.50 (interpolated from bearing capacity tables)', 'result': 1.5, 'units': 'dimensionless'}, {'step': 5, 'description': 'Bearing Capacity per Unit Area', 'formula': 'qult = Nc×c + q×Nq (where Nc = 9.0 for deep foundations)', 'calculation': 'qult = 9.0×4.50 + 3.085×1.50\nqult = 40.50 + 4.63\nqult = 45.13 ksf', 'result': 45.1275, 'units': 'ksf'}, {'step': 6, 'description': 'Total Soil Bearing Capacity', 'formula': 'Qh = Ah × qult', 'calculation': 'Qh = 1.049 × 45.13\nQh = 47.34 kips', 'result': 47.3387475, 'units': 'kips'}, {'step': 7, 'description': 'Mechanical Capacity Limit', 'formula': 'Qs = SS175 ultimate capacity × 0.8 (14" helix reduction)', 'calculation': 'Qs = 100.0 × 0.8\nQs = 80.00 kips', 'result': 80.0, 'units': 'kips'}, {'step': 8, 'description': 'Ultimate Capacity (Controlling)', 'formula': 'Qult = min(Qh, Qs)', 'calculation': 'Qult = min(47.34, 80.00)\nQult = 47.34 kips\nControlled by: Soil', 'result': 47.3387475, 'units': 'kips'}]}, {'helix_diameter': 14, 'depth': 29.0, 'helix_area': 1.049, 'soil_type': 'Sandy Lean Clay', 'spt_n_value': 10, 'cohesion': 4.5, 'friction_angle': 0, 'overburden_pressure': 3.505, 'bearing_factor_nq': 1.5, 'bearing_capacity_per_unit_area': 45.7575, 'cohesion_component': 40.5, 'friction_component': 5.2575, 'capacity_soil': 47.9996175, 'capacity_mechanical': 80.0, 'capacity_ultimate': 47.9996175, 'controlling_factor': 'Soil', 'calculation_steps': [{'step': 1, 'description': 'Helix Area Lookup', 'formula': 'Ah = Area of 14" helix', 'calculation': 'Ah = 1.049 sq.ft', 'result': 1.049, 'units': 'sq.ft'}, {'step': 2, 'description': 'Soil Properties at Helix Depth', 'formula': 'At depth = 29.0 ft', 'calculation': 'Soil Type: Sandy Lean Clay\nSPT N-value: 10\nCohesion (c): 4.50 ksf\nFriction Angle (φ): 0.0°', 'result': {'cohesion': 4.5, 'friction_angle': 0}, 'units': 'various'}, {'step': 3, 'description': 'Effective Overburden Pressure', 'formula': 'q = Σ(γ × thickness) for each layer', 'calculation': 'q = 3.505 ksf (at depth 29.0 ft)', 'result': 3.505, 'units': 'ksf'}, {'step': 4, 'description': 'Bearing Capacity Factor (Nq)', 'formula': 'Nq = f(φ = 0.0°)', 'calculation': 'Nq = 1.50 (interpolated from bearing capacity tables)', 'result': 1.5, 'units': 'dimensionless'}, {'step': 5, 'description': 'Bearing Capacity per Unit Area', 'formula': 'qult = Nc×c + q×Nq (where Nc = 9.0 for deep foundations)', 'calculation': 'qult = 9.0×4.50 + 3.505×1.50\nqult = 40.50 + 5.26\nqult = 45.76 ksf', 'result': 45.7575, 'units': 'ksf'}, {'step': 6, 'description': 'Total Soil Bearing Capacity', 'formula': 'Qh = Ah × qult', 'calculation': 'Qh = 1.049 × 45.76\nQh = 48.00 kips', 'result': 47.9996175, 'units': 'kips'}, {'step': 7, 'description': 'Mechanical Capacity Limit', 'formula': 'Qs = SS175 ultimate capacity × 0.8 (14" helix reduction)', 'calculation': 'Qs = 100.0 × 0.8\nQs = 80.00 kips', 'result': 80.0, 'units': 'kips'}, {'step': 8, 'description': 'Ultimate Capacity (Controlling)', 'formula': 'Qult = min(Qh, Qs)', 'calculation': 'Qult = min(48.00, 80.00)\nQult = 48.00 kips\nControlled by: Soil', 'result': 47.9996175, 'units': 'kips'}]}], 'total_ultimate_capacity': 129.6459375, 'calculation_method': 'Chance Individual Bearing Method'}, 'installation_specifications': {'torque_correlation_factor': 10, 'min_installation_torque_ftlb': 12964, 'max_torque_rating_ftlb': 10000, 'torque_adequate': False, 'embedment_depth_ft': 29.0, 'termination_criteria': 'Achieve both 29.0 ft depth AND 12,964 ft-lb torque', 'buckling_check': {'min_n_value': 10, 'adequate': True, 'note': 'Adequate (N > 4)'}}}, 'num_passing_designs': 3}}]}