Flat L-Type Joints

Flat L-type joints are used to connect beam elements at an angle. In regard to the value of the slant angle of adjoining elements, we distinguish perpendicular flat L-type joints (Fig. 4.33) and slant flat L-type joints (Fig. 4.34). In the first case, the

Fig. 4.30 Frontal parallel joints: a bevelled lap joint, b straight lap joint, c slant lap joint, d wedge joint, e straight bridle joints, f slant bridle joints and g multi-wedge (finger) joint

slant angle amounts to 90°, and in the second -45°. However, there is a possibility of joining elements at any angle, but maintaining their sufficient stiffness and strength. The group of perpendicular flat L-type joint includes straight lap joints, single through mortise and tenon joints, single covered mortise and tenon joints,

Fig. 4.31 Longitudinal parallel joints: a at width, b at thickness and c at width and thickness

Fig. 4.32 Longitudinal parallel joints at width: a spline rectangular, (b, c) spline trapezoidal, d spline triangular, e spline semicircular, f spline rectangular with a ledge and g spline framed

single semi-covered mortise and tenon joints, single separated mortise and tenon joints, double through mortise and tenon joints, double semi-covered mortise and tenon joints, double dowel joints. The group of slant flat L-type joints includes bevel lap joints, single bevel mortise and tenon joints, double bevel mortise and tenon joints, double bevel dowel joints, covered bevel mortise and tenon joints. Figure 4.35 shows the principles of measuring perpendicular flat L-type joints.

Fig. 4.33 Perpendicular flat L-type joints: a straight lap joint, b single through mortise and tenon joint, c single covered mortise and tenon joint, d single semi-covered mortise and tenon joint, (e, f) single separated mortise and tenon joint perpendicular flat L-type joints, g single separated mortise and tenon joint, h double through mortise and tenon joint, i double semi-covered mortise and tenon joint and j double dowel joint

Fig. 4.33 (continued)