public function setKstruktur(ChildKstruktur $v = null)
    {
        $this->singleKstruktur = $v;

        // Make sure that that the passed-in ChildKstruktur isn't already associated with this object
        if ($v !== null && $v->getStructureNode(null, false) === null) {
            $v->setStructureNode($this);
        }

        return $this;
    }