> ## Documentation Index
> Fetch the complete documentation index at: https://calcs.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Live Load Patterning

> Guide to implementing live load patterning in beam solver analysis for optimized load combinations

Live Load Patterning is a feature of the beam solver that automatically generates optimized load combinations based on structural configuration, helping identify critical loading scenarios for design.

## How It Works

Live load patterning is enabled by passing a vector of load types to be patterned to the beam solver. The solver then automatically generates combinations based on the structural layout.

### Basic Configuration

To enable load patterning, specify the load types in the `loadPattern` parameter:

```json theme={null}
{
  "type": "remote",
  "referenceId": "beam_analysis",
  "solver": "beam",
  "inputs": {
    "loadPattern": ["L"],
    // ... other beam solver inputs
  }
}
```

<ResponseField name="loadPattern" type="array" required>
  Vector containing the load types to be patterned (e.g., `["L"]` for live loads, `["L", "Lr"]` for live and roof live loads)
</ResponseField>

### Automatic Combination Generation

Behind the scenes, the solver automatically generates load combinations based on:

1. **Support locations** (default behavior)
2. **Internal pins** (treated as pattern break points, even though they're not technically supports)
3. **Brace locations** (when configured)

## Advanced Configuration

### Load Pattern Basis

You can control what structural elements are used to determine patterning locations with the `loadPatternBasis` parameter:

<ResponseField name="loadPatternBasis" type="string" default="supports">
  Defines what structural elements determine pattern boundaries:

  * `"supports"`: Based on support locations (default)
  * `"braces"`: Based on any brace locations
  * `"Brace X"`: Based on specific brace type X only
</ResponseField>

```json theme={null}
{
  "inputs": {
    "loadPattern": ["L"],
    "loadPatternBasis": "supports", // or "braces" or "Brace 1"
    // ... other inputs
  }
}
```

## Patterning Behavior

### Complete Spans

For loads that completely cover individual spans, the solver will pattern by including or excluding the load from each span to find maximum effects.

### Partially-Loaded Spans

If a load extends across more than one span but doesn't completely cover any span, it will still be included in the patterning analysis.

<Note>
  Loads that partially cover spans are still considered in the patterning process, ensuring comprehensive analysis of all loading scenarios.
</Note>

## Implementation Example

```json theme={null}
{
  "type": "remote",
  "referenceId": "continuous_beam_analysis",
  "solver": "beam",
  "inputs": {
    "spans": [
      {"length": 6000, "loads": [...]},
      {"length": 8000, "loads": [...]},
      {"length": 6000, "loads": [...]}
    ],
    "supports": [
      {"location": 0, "type": "pin"},
      {"location": 6000, "type": "roller"},
      {"location": 14000, "type": "roller"},
      {"location": 20000, "type": "pin"}
    ],
    "loadPattern": ["L"], // Pattern live loads
    "loadPatternBasis": "supports",
    "combinations": [
      {"name": "ULS", "factors": {"D": 1.2, "L": 1.6}},
      {"name": "SLS", "factors": {"D": 1.0, "L": 1.0}}
    ]
  }
}
```

## Benefits of Load Patterning

1. **Automatic Optimization**: Finds the most critical loading scenarios without manual specification
2. **Comprehensive Analysis**: Considers all possible load arrangements that could produce maximum effects
3. **Code Compliance**: Ensures analysis meets structural code requirements for live load patterning
4. **Efficiency**: Reduces manual effort in defining load combinations

## Best Practices

1. **Load Type Selection**: Include all relevant variable loads that should be patterned (typically live loads, roof live loads, snow loads)

2. **Basis Selection**:
   * Use `"supports"` for most continuous beam scenarios
   * Use `"braces"` when lateral bracing significantly affects behavior
   * Use specific brace types when different brace types have different structural significance

3. **Combination Design**: Ensure your load combinations work effectively with patterned loads

4. **Result Interpretation**: Remember that patterned results represent enveloped maximum/minimum values across all pattern scenarios

## Output Interpretation

When load patterning is enabled:

* Results represent enveloped maximum and minimum values
* Critical load patterns are automatically identified
* Design forces consider all possible loading arrangements
* Output includes information about which pattern produced critical results

<Info>
  Load patterning is particularly important for continuous beam analysis where different loading arrangements can produce significantly different internal forces and deflections.
</Info>

<Warning>
  When using load patterning with complex loading scenarios, ensure that your load definitions are compatible with patterning algorithms and that all relevant loads are properly categorized by type.
</Warning>