Special characters in URL are encoded according to RFC 3986. You could get the encoded URL by rawurlencode().
<html>
<head>
<title>PHP - Encode and Decode URL</title>
</head>
<body>
<h2 style="text-decoration: underline;">rawurlencode()</h2>
<?php
$url = "https://ykyuen.wordpress.com/2009/10/11/密舒的BB/";
print "<p>".rawurlencode($url)."</p>";
?>
<br/>
<h2 style="text-decoration: underline;">rawurldecode()</h2>
<?php
$url = rawurlencode($url);
print "<p>".rawurldecode($url)."</p>";
?>
</body>
</html>
As you can see above, you could obtain the Chinese characters and other special characters by rawurldecode(). Here is the result

Done =)
Reference:
