Table II.

Diameter of Bolt (in inches)	Diameter Factor
1/4	2.50
3/8	1.95
1/2	1.68
5/8	1.52
3/4	1.41
7/8	1.33
1	1.27
1-1/4	1.19
1-1/2	1.14
1-3/4	1.10
2	1.07
2-1/2	1.03
3 and over	1.00

(A) The safe working stress for a given value of L/D is the product of three factors:

(I) The basic stress perpendicular to the grain taken from the table in paragraph (7)(i).

(II) The percentage from the table set forth in clause (A).

(III) The factor for bolt diameter, as set forth in clause (B).

(B) No reduction need be made when wood splice plates are used except that the safe load perpendicular to the grain should never exceed the safe load parallel to the grain for any given size and quality of bolt and timber.

(C) The common bolts referred to in Table I are those having a yield point of approximately 45,000 pounds per square inch.

(D) The high-strength bolts referred to in Table I are those having a yield point of approximately 125,000 pounds per square inch.

(8) For other materials. Other materials when used shall be so designed and proportioned that their stresses do not exceed the allowable unit stresses generally accepted as safe by engineering practice.

Source

The provisions of this § 15.18 adopted August 15, 1933; amended through July 1, 1968.

Cross References

This section cited in 34 Pa. Code § 15.11 (relating to applicability); and 34 Pa. Code § 15.17 (relating to materials).