# 5.3 Load Factors and Combinations

**shall be at least equal to the effects of factored loads in Table 5.3.1, with exceptions and additions in 5.3.3 through 5.3.12.**

*U***Table 5.3.1—Load combinations**

Load combination | Equation | Primary load |
---|---|---|

U = 1.4D | (5.3.1a) | D |

U = 1.2D + 1.6L + 0.5(L or _{r}S or R) | (5.3.1b) | L |

U = 1.2D + 1.6(L or _{r}S or R) + (1.0L or 0.5W) | (5.3.1c) | L or _{r}S or R |

U = 1.2D + 1.0W + 1.0L + 0.5(L or _{r}S or R) | (5.3.1d) | W |

U = 1.2D + 1.0E + 1.0L + 0.2S | (5.3.1e) | E |

U = 0.9D + 1.0W | (5.3.1f) | W |

U = 0.9D + 1.0E | (5.3.1g) | E |

**shall include (a) through (f):**

*L*(a) Concentrated live loads

(b) Vehicular loads

(c) Crane loads

(d) Loads on hand rails, guardrails, and vehicular barrier systems

(e) Impact effects

(f) Vibration effects

**shall be considered in combination with other loads if the effects of**

*T***can adversely affect structural safety or performance. The load factor for**

*T***shall be established considering the uncertainty associated with the likely magnitude of**

*T***, the probability that the maximum effect of**

*T***will occur simultaneously with other applied loads, and the potential adverse consequences if the effect of**

*T***is greater than assumed. The load factor on**

*T***shall not have a value less than 1.0.**

*T***is present, it shall be included in the load combination equations of 5.3.1 in accordance with (a), (b), (c) or (d):**

*F*(a) If ** F** acts alone or adds to the effects of

**, it shall be included with a load factor of 1.4 in Eq. (5.3.1a).**

*D*(b) If ** F** adds to the primary load, it shall be included with a load factor of 1.2 in Eq. (5.3.1b) through (5.3.1e).

(c) If the effect of ** F** is permanent and counteracts the primary load, it shall be included with a load factor of 0.9 in Eq. (5.3.1g).

(d) If the effect of ** F** is not permanent but, when present, counteracts the primary load,

**shall not be included in Eq. (5.3.1a) through (5.3.1g).**

*F***is present, it shall be included in the load combination equations of 5.3.1 in accordance with (a), (b), or (c):**

*H*(a) If ** H** acts alone or adds to the primary load effect, it shall be included with a load factor of 1.6.

(b) If the effect of ** H** is permanent and counteracts the primary load effect, it shall be included with a load factor of 0.9.

(c) If the effect of ** H** is not permanent but, when present, counteracts the primary load effect,

**shall not be included.**

*H***shall include internal load effects due to reactions induced by prestressing with a load factor of 1.0.**

*U*### Related Code Sections

*combination*with other

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*load*

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*load*

*factor*on live

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*loads*(c) Crane

*loads*(d)

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