想问下为啥圆形井盖材质不可以改成steel呢，建模板时候材质只有Brick red rough cut可以选，选别的话，Attached Material 处只显示 None
您好，请参考下面这个帖子：
https://communities.bentley.com/communities/other_communities/chinafirst/f/openroads-powercivil-bridgemaster/187976/thread