Shear strength ratio

Symbol	τ_{B/R_m}
Unit	-
Attribute-ID	vdi_2230_shearing_strength_ratios
Numeric ID	19084
Value Type	PMDouble

The shear strength ratio τ_B/R_m is needed to calculate a possible shearing of the thread (R11), as well as the safety against shearing of the bolt (R12).

The following selection options are available:

User specified, direct input

The shear strength ratio corresponding to the selected strength grade; e.g., 0.60 for strength grade 12.9

	DIN EN ISO 898-1					DIN EN ISO 3506-1
Strength grade	4.6	5.6	8.8	10.9	12.9	50	70	80
τ_B/R_m	0.70	0.70	0.65	0.62	0.60	0.80	0.72	0.68

Table from: VDI 2230 Part 1, VDI Verlag Düsseldorf, 2015, p. 104, "Table 7. Shear strength ratios for bolts of the strength grades according to DIN EN ISO 898-1 or DIN EN ISO 3506-1"