To control any loss of the compressive residual stress introduced in a weld toe by the peening treatment while using a structure having a weld joint of a steel member.

Impact dents 202a, 202b having the radius R of curvature of ≥1.0 mm and ≤10.0 mm, and having the depth of ≤1.0 mm as the depth in the thickness direction from a surface of a weld toe are formed in the weld toe. For each steel plate constituting an inner bottom plate 102a and a lower stool slant plate 103a, the yield stress in each steel plate is ≥(10/9) times the maximum value of the compressive stress of each hot-spot stress in the weld toes 302a and 302b.