替换多维json中的选项卡

I have a multidimensional json with serialized with json_encode and I want to replace the tab \t char with str replace in php, I tried a multiple things but they don't work.

The structure is:

{
    "direccion": "Av. Pr\u00edncipe de Gales 7203, La Reina, Regi\u00f3n Metropolitana",
    "comuna": "La Reina",
    "region": " Regi\u00f3n Metropolitana",
    "x": "-70.55722960000",
    "y": "-33.438904"
},
{
    "direccion": "Av. Irarr\u00e1zaval 3798, \u00d1u\u00f1oa, Regi\u00f3n Metropolitana",
    "comuna": "\u00d1u\u00f1oa",
    "region": " Regi\u00f3n Metropolitana",
    "x": "-70.58979",
    "y": "-33.4554247"
},
{
    "direccion": "Av. Los Presidentes 7640, Pe\u00f1alol\u00e9n, Regi\u00f3n Metropolitana \t",
    "comuna": "Pe\u00f1alol\u00e9n",
    "region": " Regi\u00f3n Metropolitana",
    "x": "-70.55725259999",
    "y": "-33.486479"
},
{
    "direccion": "Av. Jos\u00e9 Pedro Alessandri 4470, Macul, Regi\u00f3n Metropolitana",
    "comuna": "Macul",
    "region": " Regi\u00f3n Metropolitana",
    "x": "-70.59820509999",
    "y": "-33.4786217"
},
{
    "direccion": "Av. La Florida 7488, La Florida, Regi\u00f3n Metropolitana",
    "comuna": "La Florida",
    "region": " Regi\u00f3n Metropolitana",
    "x": "-70.57856800000",
    "y": "-33.5224544"
},
{
    "direccion": "Victor Manuel 1560, Santiago, Regi\u00f3n Metropolitana",
    "comuna": "Santiago",
    "region": " Regi\u00f3n Metropolitana",
    "x": "-70.64127100000",
    "y": "-33.4659235"
},
{
    "direccion": "Av. Ricardo Cumming 291, Santiago, Regi\u00f3n Metropolitana",
    "comuna": "Santiago",
    "region": " Regi\u00f3n Metropolitana",
    "x": "-70.66805399999",
    "y": "-33.4416077"
},
{
    "direccion": "Av. Independencia 1699, Independencia, Regi\u00f3n Metropolitana",
    "comuna": "Independencia",
    "region": " Regi\u00f3n Metropolitana",
    "x": "-70.65902470000",
    "y": "-33.4116498"
},
{
    "direccion": "Av. Pedro Fontova 7281, Huechuraba, Regi\u00f3n Metropolitana",
    "comuna": "Huechuraba",
    "region": " Regi\u00f3n Metropolitana",
    "x": "-70.67051839999",
    "y": "-33.3550624"
},
{
    "direccion": "Bernardo O`Higgins 438, Quilicura, Regi\u00f3n Metropolitana \t",
    "comuna": "Quilicura",
    "region": " Regi\u00f3n Metropolitana",
    "x": "-70.73194939999",
    "y": "-33.3691952"
}

I tried to use preg_replace on the json encoded string but it doesn't work as expected.

$json = json_encode(array("cc"=>$result, "beneficios"=>$new_results) );
    $json = preg_replace('\t', "Metropolitanaqq", $json);
    echo "categorias('".$json."')";

Any suggestions?

Thanks!