Function $ (document) .ready () only executes once

I have an Asp.Net application that has a menu on a main screen that has 2 links, each one for a page.

When I click on the first link and load the first page, the $(document).ready() function runs right and loads all the components I need.

When I click on the second link, reviewing Firebug step by step, I notice that the $(document).ready() function is not executed. What is the reason for this?

This application uses a layout page that is rendered before.

Function $(document).ready()

$(document).ready(function () {
    $('#spn').spinit({ min: 1, max: 100, stepInc: 1, pageInc: 10, height: 13, initValue: 95/*,callback: filtraModeloGrafico4*/});

    //Carrega o datepicker
    jQuery('#_InitialDateValue').datetimepicker( { format: 'd/m/Y H:i' } );
    jQuery('#_FinalDateValue').datetimepicker({ format: 'd/m/Y H:i' });

    jQuery('#_InitialDateValue2').datetimepicker({ format: 'd/m/Y H:i' });

    //Carrega a combo com os dias da semana
    $('#idComboTurno').multiselect({
        includeSelectAllOption: true,
        nonSelectedText: 'Select a week day',
        nSelectedText: 'days',
        numberDisplayed: 0
    });

});

The name of the file that has the function $(document).ready() is site.js

This page loads everything right:

@{
    ViewBag.Title = "Sequence Inspection - Graphics Report";
}

@Scripts.Render("~/Scripts/site.js")

<div class="row-fluid">
    <form class="form-inline">
        <div class="control-group span12">
         // Código...
         </div>
    </form>
</div>

Page that does not load the function $(document).ready()

@{
    ViewBag.Title = "Sequence Inspection - Failure Report";
}

@Scripts.Render("~/Scripts/site.js")

<div class="row-fluid">
@using (Html.BeginForm("ExportaExcel", "FailureReport", FormMethod.Post, new { @class = "form-inline" }))
{
  //Código HTML
}
</div>