feat: add ACI 318-25 support (one-way slab flexure and shear)

docs/api/codes/aci318_25/flexure.md

@@ -0,0 +1,55 @@
+# Flexural strength
+
+Flexural strength functions according to ACI 318-25, Ch. 22.2-22.3.
+
+## Equilibrium helpers
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.stress_block_depth_sr
+```
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.stress_block_depth_dr
+```
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.neutral_axis_depth
+```
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.eps_t_from_c
+```
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.eps_s_prime
+```
+
+## Nominal moment strength
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.Mn_singly_reinforced
+```
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.Mn_doubly_reinforced
+```
+
+## Reinforcement limits
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.As_min_slab
+```
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.As_min_beam
+```
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.As_max_check
+```
+
+## Design helpers
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.As_required
+```

docs/api/codes/aci318_25/index.md

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+(api-aci318_25)=
+# ACI 318-25
+
+:::{toctree}
+
+Material properties for concrete <material_concrete>
+Material properties for reinforcement steel <material_reinforcement>
+Strength reduction factors <strength_reduction>
+Flexural strength <flexure>
+One-way shear strength <shear>
+One-way slab design rules <one_way_slab>
+:::

docs/api/codes/aci318_25/material_concrete.md

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+# Material properties for concrete
+
+Functions for concrete material properties according to ACI 318-25, Chapter 19.
+
+## Modulus of elasticity
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.Ec
+```
+
+## Modulus of rupture
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.fr
+```
+
+## Splitting tensile strength
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.fct
+```
+
+## Whitney stress block parameters
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.beta1
+```
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.alpha1
+```
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.eps_cu
+```
+
+## Lightweight concrete
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.lambda_factor
+```

docs/api/codes/aci318_25/material_reinforcement.md

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+# Material properties for reinforcement steel
+
+Functions for reinforcement material properties according to ACI 318-25, Chapter 20.
+
+## Modulus of elasticity
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.Es
+```
+
+## Design yield strength
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.fy_design
+```
+
+## Yield strain
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.epsyd
+```
+
+## ASTM grade lookup
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.reinforcement_grade_props
+```

docs/api/codes/aci318_25/one_way_slab.md

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+# One-way slab design rules
+
+One-way slab design rules according to ACI 318-25, Chapter 7.
+
+## Minimum thickness
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.min_thickness
+```
+
+## Shrinkage and temperature reinforcement
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.As_shrinkage_temperature
+```
+
+## Bar spacing limits
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.max_bar_spacing_flexure
+```
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.max_bar_spacing_shrinkage
+```
+
+## Critical section for shear
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.shear_critical_section_offset
+```

docs/api/codes/aci318_25/shear.md

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+# One-way shear strength
+
+One-way shear strength functions according to ACI 318-25, Ch. 22.5.
+
+## Size effect
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.lambda_s
+```
+
+## Concrete shear contribution
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.Vc_detailed
+```
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.Vc_simplified
+```
+
+## Steel shear contribution
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.Vs
+```
+
+## Nominal shear strength
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.Vn
+```
+
+## Cross-section check
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.check_cross_section
+```
+
+## Minimum shear reinforcement
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.Av_min_per_s
+```
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.shear_reinforcement_required
+```
+
+## Maximum stirrup spacing
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.max_stirrup_spacing
+```

docs/api/codes/aci318_25/strength_reduction.md

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+# Strength reduction factors
+
+Strength reduction factors according to ACI 318-25, Chapter 21.
+
+ACI 318 uses LRFD -- strength reduction factors (phi) are applied at the
+member capacity level, not at the material level. Design functions in
+this library return nominal strengths; phi is applied externally by the caller.
+
+## Moment, axial force, or combined
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.phi_flexure
+```
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.section_classification
+```
+
+## Shear
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.phi_shear
+```
+
+## Torsion
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.phi_torsion
+```
+
+## Bearing
+
+```{eval-rst}
+.. autofunction:: structuralcodes.codes.aci318_25.phi_bearing
+```

docs/api/codes/index.md

@@ -5,6 +5,7 @@
 :maxdepth: 2
 
 General functions <general>
+ACI 318-25 <aci318_25/index>
 Eurocode 2 (2004) <ec2_2004/index>
 Eurocode 2 (2023) <ec2_2023/index>
 fib Model Code 2010 <mc2010/index>