Belting or screaming and shouting when singing is thought by some people as being powerful voices. These types of singing put a lot of pressure on the vocal folds and can cause tension in the surrounding muscles. Singing this way is extremely unhealthy to the singing voice.
Hundreds if not thousands of years ago, excellent voice projection techniques were developed by singers of that time who were capable of being heard across a crowded theatre or auditorium without the aid of electronic amplification. How else could speakers and singers be heard in the likes of early Roman stadiums such as the Coliseum.
Today the use of modern technology has provided singers with the means of being heard regardless of their vocal capabilities. Furthermore, a sound engineer with the proper sound equipment can mask or even correct vocal errors and make a weak voice sound much stronger and that could be the reasons why so many of the skills required for developing a powerful voice are conveniently neglected by many singers nowadays.
Yes, there are even professional singers who shout or using vocal cords damaging techniques when singing. They will they invariably suffer with vocal problems sooner or later.
Yes, rock singers scream and shout a lot. However, rough and raspy voices are accepted in that genre of music. In fact, many rock singers have damaged vocal cords and that is why even when they are speaking normally, their voices are coarse and raspy.
Although there are singers who are blessed with naturally strong voices, they are just the minority. For the majority of us, there are no short cuts to developing powerful voices and this can take months or even years with the right vocal exercises to develop.
Strong and powerful voices are developed through a combination of good breathing control, excellent posture, correct singing techniques and of course plenty of practice with a good vocal teacher.
There are two important things to remember when training to sing loudly with a powerful voice. If your vocal cords are hurting, stop singing. If you feel odd or uncomfortable, stop singing. These are your singing mechanism's way of telling you that something is wrong.
Never attempt to push your voice past its natural limitations. You can extend your vocal limitation by practicing incrementally. It is perfectly alright to explore and experiment with your voice as you are even encouraged to do so except that you should avoid anything that puts a strain on your vocal mechanism.
One more important element in protecting your voice from permanent damage which many singers do not do is warming up and cooling down your voice before and after singing. This is extremely important but is often neglected by professional and amateur singers alike.
So if you want to have a strong and powerful singing voice, use good techniques to project your voice instead of shouting and screaming which in time will cause you to damage your voice permanently and end your career as a singer.