FIELD: mechanical engineering. SUBSTANCE: unit includes first flexible member having central portion folded in half forming loop extending through slot from first side of wall of structure outside from second side and outer blade-form parts on each end of central portion secured to first side of wall near slot. First flexible member includes also many unidirectional strengthening filaments in matrix material which are parallel to one another in central portion and diverging in each outer part. Second flexible member having periphery passing around slot and outer parts of first flexible member is secured to first flexible member and to first side of flexible wall of structure. EFFECT: avoidance of local concentrations of stresses. 7 cl, 6 dwg
