Do not apply the provisions for design tandem as described in Article 3.6.1.3.1.

Do not apply the variable axle spacing described in Article 3.6.1.2.2. Set the spacing between the two 32.0-kip axles equal to 14.0 ft.

Unless site-specific information is available, assume cohesionless soil with unit weight equal to 120 pcf and friction angle equal to 30°. Use Rankine's active earth pressure coefficient to compute lateral earth pressure. Precast box culverts may be designed for the earth loads defined in ASTM C1577.

Do not apply the water loads indicated in Table 3.4.1-1 for structural analyses of concrete culverts, unless warranted by site conditions.

Limit the equivalent height of soil, $h_{eq}$
, from Table 3.11.6.4.1 to a maximum value of 4.0 ft.