It reaaaally depends on the scene and what sort of awful thing it is and if you're writing it or drawing it. Things like showing it in shadows or silhouettes and the typical anime bright pink blood negate some of the graphicness of violence Quite honestly I saw one where a young girl was ripped apart by dragons, the silhouetted versions were in many ways more impactful than seeing the blood and gore when I watched the uncensored version. Gushing blood can also look pretty dumb.
I think the best way to do graphic scenes is to sort of unstate them. If you want to avoid shock value, don't linger on them. Especially if you're killing a character violently or similar. It happens, but don't linger on it. Don't show lots of shots of it or from all angles. Just BAM it happened and then carry on into people's reactions ect. More emotional terrible things, focus on the victim's face, or little details, but again, don't linger.
I think a lot of it depends on tone of your work too though. A darker series can get away with a lot more without being called going for shock value than a series that was bright and then suddenly went dark with some big shocking event. And about how you handle it. Show it as a scary emotional, earth shaking thing rather than just something that happened. I've seen so many shows that think they're being edgy by doing something dramatic and big but it actually has no impact on the plot. It has to have the right impact for the size of the event.