SO http://is.gd/RUGcQb

HTML

<link rel="stylesheet" href="//netdna.bootstrapcdn.com/bootstrap/3.0.0/css/bootstrap.min.css">
<div class="container">

<div class="row">

<div class="col-md-6" >
  <div class="row">
  <div class="col-md-11" style="border: solid 1px #000; background-color: blue">nested row col-md-11</div>
  </div>
</div>
  
  <div class="col-md-6">
  <div class="row">
  <div class="col-md-11 col-md-offset-1" style="border: solid 1px #000; background-color: blue">nested row col-md-11</div>
  </div>
</div>
  
  
  
</div>

</div>

CSS

.col-md-11{
    background-color:#fff;
    height:100px;
  }  
.container{
    background-color:#ffc;
    height:120px;
}