$A = array(
array("a1"=>1,"b1"=>2,"c1"=>"A"),
array("a1"=>1,"b1"=>16,"c1"=>"Z"),
array("a1"=>3,"b1"=>8,"c1"=>"A"));

$B = array(
array("a2"=>1,"b2"=>2,"b2"=>"A"),
array("a2"=>1,"b2"=>16,"b2"=>"G"),
array("a2"=>3,"b2"=>8,"b2"=>"A"));

$C=array(
array("a1"=>1,"b1"=>2,"c1"=>"A"),
array("a1"=>1,"b1"=>16,"c1"=>"Z"),
array("a1"=>3,"b1"=>8,"c1"=>"A"),
array("a2"=>1,"b2"=>2,"b2"=>"A"),
array("a2"=>1,"b2"=>16,"b2"=>"G"),
array("a2"=>3,"b2"=>8,"b2"=>"A"));

$C = array_merge($A, $B);
print_r($C);

Array (
    [0] => Array (
        [a1] => 1
        [b1] => 2
        [c1] => A
        )
        [1] => Array (
            [a1] => 1
            [b1] => 16
            [c1] => Z )
        [2] => Array (
            [a1] => 3
            [b1] => 8
            [c1] => A
        )
        [3] => Array (
            [a2] => 1
            [b2] => A
        )
        [4] => Array (
            [a2] => 1
            [b2] => G
        )
        [5] => Array (
            [a2] => 3
            [b2] => A
        )
    )

$C = array_merge($A, $B);

$array1 = array("farbe" => "rot", 2, 4);
$array2 = array("a", "b", "farbe" => "grün", "form" => "trapezoid", 4);
$result = array_merge($array1, $array2);
print_r($result);

foreach($B as $key => $value){
    $C[$key] = array_merge($A[$key], $B[$key]);
}

public function array_interlace() {
    $args = func_get_args();
    $total = count($args);

    if($total < 2) {
        return FALSE;
    }

    $i = 0;
    $j = 0;
    $arr = array();

    foreach($args as $arg) {
        foreach($arg as $v) {
            $arr[$j] = $v;
            $j += $total;
        }

        $i++;
        $j = $i;
    }

    ksort($arr);
    return array_values($arr);
}

$a = array('a', 'b', 'c', 'd');
$b = array('a','e', 'f', 'g');
$c = array('h', 'i', 'j');
$d = array('k', 'l', 'm', 'n', 'o');

print_r(array_interlace($a, $b, $c, $d));
Array
(
[0] => a
[1] => a
[2] => h
[3] => k
[4] => b
[5] => e
[6] => i
[7] => l
[8] => c
[9] => f
[10] => j
[11] => m
[12] => d
[13] => g
[14] => n
[15] => o