# Load Rating Combination Table \[TB]

Each row defined in this section serves as an input to load rating templates and enables mapping of the analysis results to load rating objects.

To utilize this object, users must ensure that the related Result Extraction Cases and Live Load Cases have been properly defined. Per AASHTO MBE, strength is the primary limit state for load rating; service limit states are selectively applied. A common pattern is to define two separate Load Rating Combination Tables — one for strength factors and one for service factors — and assign them to the Concrete Girder Load Rating object as the Strength and Service inputs.

Each **γ**\* parameter is a dimensionless load factor applied to the analysis result of the case selected in the adjacent parameter on the same row. Indices (1, 2, 3 …) simply enumerate multiple live-load cases in a category; the mapping from index to vehicle or permit is set by the user.

### Permanent Loads

**γDC (max):** Maximum load factor for composite and non-composite dead-load cases. Typically 1.25 for strength limit states (AASHTO LRFD Table 3.4.1-2, or DOT amendments).

**γDC (min):** Minimum load factor for the same cases. Typically 0.9.

**DC1:** Result Extraction Case for non-composite dead load (self-weight of girder, cross frames, formwork, wet deck).

**DC2:** Result Extraction Case for composite dead load (barriers and other loads applied after composite action).

**γDW (max):** Maximum load factor for the wearing-surface / utilities case (DW). Typically 1.5.

**γDW (min):** Minimum load factor for DW. Typically 0.65.

**DW:** Result Extraction Case for wearing surface and utilities.

**γP (max):** Maximum load factor for permanent loads other than dead loads.

**γP (min):** Minimum load factor for permanent loads other than dead loads.

**Permanent Loads:** Result Extraction Case for the general permanent loads group, previously created in the Result Extraction (from Stages) object.

### PS Loads

Prestressing effects and their time-dependent losses can be factored independently of the dead-load cases. Assign Analysis Cases generated by the Girder Tendon objects.

**γPS:** Factor for the prestressing load case.

**PS:** Analysis Case holding the prestressing effects.

**γPS Loss (Relaxation):** Factor applied to the tendon relaxation loss case.

**PS (Relaxation):** Analysis Case holding the relaxation loss.

**γPS Loss (Elastic Shortening):** Factor applied to the elastic-shortening loss case.

**PS (Elastic Shortening):** Analysis Case holding the elastic-shortening loss.

**γCR:** Factor applied to the creep case.

**PS (Creep):** Analysis Case holding the creep effects.

**γSH:** Factor applied to the shrinkage case.

**PS (Shrinkage):** Analysis Case holding the shrinkage effects.

### Design Load

Design Load Rating uses HL-93 and must comply with AASHTO LRFD using the bridge's current dimensions and properties.

**γLL (Inventory):** Live-load factor used for the inventory rating level.

**γLL (Operating):** Live-load factor used for the operating rating level.

**LL:** Live-load Analysis Case for the design load rating.

### Legal Load

Legal Load Rating applies to legal trucks (the Notional Rating Load or state legal loads). Up to 20 (γLL, LL) pairs can be populated; leave unused rows at NULL.

**γLL 1:** Factor applied to live-load case 1.

**LL 1:** Live-load Analysis Case 1.

**γLL 2:** Factor applied to live-load case 2.

**LL 2:** Live-load Analysis Case 2.

**γLL 3:** Factor applied to live-load case 3.

**LL 3:** Live-load Analysis Case 3.

**γLL 4:** Factor applied to live-load case 4.

**LL 4:** Live-load Analysis Case 4.

**γLL 5:** Factor applied to live-load case 5.

**LL 5:** Live-load Analysis Case 5.

**γLL 6:** Factor applied to live-load case 6.

**LL 6:** Live-load Analysis Case 6.

**γLL 7:** Factor applied to live-load case 7.

**LL 7:** Live-load Analysis Case 7.

**γLL 8:** Factor applied to live-load case 8.

**LL 8:** Live-load Analysis Case 8.

**γLL 9:** Factor applied to live-load case 9.

**LL 9:** Live-load Analysis Case 9.

**γLL 10:** Factor applied to live-load case 10.

**LL 10:** Live-load Analysis Case 10.

**γLL 11:** Factor applied to live-load case 11.

**LL 11:** Live-load Analysis Case 11.

**γLL 12:** Factor applied to live-load case 12.

**LL 12:** Live-load Analysis Case 12.

**γLL 13:** Factor applied to live-load case 13.

**LL 13:** Live-load Analysis Case 13.

**γLL 14:** Factor applied to live-load case 14.

**LL 14:** Live-load Analysis Case 14.

**γLL 15:** Factor applied to live-load case 15.

**LL 15:** Live-load Analysis Case 15.

**γLL 16:** Factor applied to live-load case 16.

**LL 16:** Live-load Analysis Case 16.

**γLL 17:** Factor applied to live-load case 17.

**LL 17:** Live-load Analysis Case 17.

**γLL 18:** Factor applied to live-load case 18.

**LL 18:** Live-load Analysis Case 18.

**γLL 19:** Factor applied to live-load case 19.

**LL 19:** Live-load Analysis Case 19.

**γLL 20:** Factor applied to live-load case 20.

**LL 20:** Live-load Analysis Case 20.

### Emergency Load

Up to 10 (γLL, LL) pairs define the Emergency Load rating — assessment of the bridge's capacity under emergency vehicles. Each row reuses the same meaning as the Legal Load rows above, but within the Emergency limit state.

**γLL 1:** Factor applied to emergency live-load case 1.

**LL 1:** Emergency live-load Analysis Case 1.

**γLL 2:** Factor applied to emergency live-load case 2.

**LL 2:** Emergency live-load Analysis Case 2.

**γLL 3:** Factor applied to emergency live-load case 3.

**LL 3:** Emergency live-load Analysis Case 3.

**γLL 4:** Factor applied to emergency live-load case 4.

**LL 4:** Emergency live-load Analysis Case 4.

**γLL 5:** Factor applied to emergency live-load case 5.

**LL 5:** Emergency live-load Analysis Case 5.

**γLL 6:** Factor applied to emergency live-load case 6.

**LL 6:** Emergency live-load Analysis Case 6.

**γLL 7:** Factor applied to emergency live-load case 7.

**LL 7:** Emergency live-load Analysis Case 7.

**γLL 8:** Factor applied to emergency live-load case 8.

**LL 8:** Emergency live-load Analysis Case 8.

**γLL 9:** Factor applied to emergency live-load case 9.

**LL 9:** Emergency live-load Analysis Case 9.

**γLL 10:** Factor applied to emergency live-load case 10.

**LL 10:** Emergency live-load Analysis Case 10.

### Permit Load

Permit Load Rating applies to vehicles that exceed legal weight limits and require a permit. Up to 10 (γLL, LL) pairs define the permit rating.

**γLL 1:** Factor applied to permit live-load case 1.

**LL 1:** Permit live-load Analysis Case 1.

**γLL 2:** Factor applied to permit live-load case 2.

**LL 2:** Permit live-load Analysis Case 2.

**γLL 3:** Factor applied to permit live-load case 3.

**LL 3:** Permit live-load Analysis Case 3.

**γLL 4:** Factor applied to permit live-load case 4.

**LL 4:** Permit live-load Analysis Case 4.

**γLL 5:** Factor applied to permit live-load case 5.

**LL 5:** Permit live-load Analysis Case 5.

**γLL 6:** Factor applied to permit live-load case 6.

**LL 6:** Permit live-load Analysis Case 6.

**γLL 7:** Factor applied to permit live-load case 7.

**LL 7:** Permit live-load Analysis Case 7.

**γLL 8:** Factor applied to permit live-load case 8.

**LL 8:** Permit live-load Analysis Case 8.

**γLL 9:** Factor applied to permit live-load case 9.

**LL 9:** Permit live-load Analysis Case 9.

**γLL 10:** Factor applied to permit live-load case 10.

**LL 10:** Permit live-load Analysis Case 10.


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