求翻译这段话

Several techniques were applied to strengthen beamcolumn
joints. These techniques include the use of concrete
jackets, bolted steel plates and jacketing using corrugated
steel sheets [1–5]. Several beam-column joints
strengthened using various steel-plate and angle rehabilitation
systems were tested. The strengthening
approaches varied from the simple to the complex and
were shown to be effective in improving the joint shear
strength and ductility. One of the important problems
encountered in the rehabilitation of beam-column joints
is the difficulty in providing effective confinement to the
joint. From tests on the rehabilitation of lap splices in
rectangular reinforced concrete columns using flat steel
sheets, Ghobarah et al. [6] proposed the use of mechanical
anchors to prevent the bulging problems associated
with flat steel jackets. The procedure enables the effective
use of flat steel-jackets in the rehabilitation of columns
and joints. In another attempt to reduce the steel
jacket bulging when rehabilitating the joints of rectangular
columns, Ghobarah et al. [5] investigated a retrofitting
technique in which corrugated steel jackets were
used to encase the joint. The proposed method was found
to be quite efficient in preventing the bulging of the
jacket and in upgrading the shear strength of the joint.