'You are a brick!' is a correct saying in English, but it's a bit old-fashioned. We usually say it to mean someone is reliable, supportive (strong and dependable like a brick) or helpful, but it could also mean generous or kind-hearted. It is always a compliment and it's a nice thing to say to someone :)

Though the phrase "you are a brick" is not used in the US, it could probably be confused with another common phrase here: "You are thick as a brick." Which means "you are very stupid". So, be careful with whom you use the phrase.

虽然我是收教育的人，也生活很多年，但上面的用brick的句子， 我没听过