Cau 9. Cac yt phu thuoc bien dang deo cua lop bm toi do nham

Bm bien dang deo cac cau truc tinh the nho bien thanh cau truc soi lam thay doi hinh dang va kich thuoc nhap nho. Khi gia cong v = 15-20 m/ph. Thi nhiet cat , luc cat deu tang gay ra bien dang deo manh ==> leo dao.

V tang toi gia tri xac dinh khong co leo dao thi do bong tang

Hinh ve anh huong cua van toc cat toi chieu cao nhap nho.

Khi gia cong kim loai gion v nho thi Rz tang. V lon thi ko co leo dao thi Rzgiam

S thay doi thi Rz cung thay doi. Hinh ve.

Loai vat lieu cung a/h toi bien dang de ova a/h toi Rz