รบกวนสอบถามเรื่องแการปลงตัวแปรจาก String เป็น Array ด้วยภาษา Php

<?php
$start_date = array('2016-01-11','2016-01-11','2016-01-11','2016-01-11','2016-01-11','2016-01-11','2016-01-11','2016-01-11','2016-01-11','2016-01-11');
print_r($start_date);

?>

<?php
$start_date = "2016-01-112016-01-122016-01-112016-01-122016-01-122016-01-122016-01-132016-01-132016-01-132016-01-142016-01-142016-01-152016-01-152016-01-162016-01-16"; 
$start=0;
$run=10;
$len=strlen($start_date);
$dataArray=array();
echo $len;
for($start=0;$start<$len;$start++){
    if ($start % 10 == 0) {
        $data=substr($start_date, $start, $run);
         array_push($dataArray,$data);
    }
}

print_r($dataArray);

?>

$start_date = "2016-01-112016-01-122016-01-112016-01-122016-01-122016-01-122016-01-132016-01-132016-01-132016-01-142016-01-142016-01-152016-01-152016-01-162016-01-16"; 
	$x = str_split($start_date, 10);
	print_r($x);