| SECTION 2108 STRENGTH DESIGN
OF MASONRY
2108.1 General. The design
of masonry structures using strength design shall comply with
Section 2106 and the requirements
of Chapters 1 and 3 of ACI 530/ASCE 5/TMS 402, except as modified
by Sections 2108.2 through 2108.4.
Exception: AAC masonry
shall comply with the requirements of Chapter 1 and Appendix
A of ACI 530/ASCE 5/TMS 402.
2108.2 ACI 530/ASCE 5/TMS
402, Section 3.3.3.3 development. Add the following text
to Section 3.3.3.3:
The required development length
of reinforcement shall be determined by Equation (3-15),
but shall not be less than 12 inches (305 mm) and need not
be greater than 72 db.
2108.3 ACI 530/ASCE 5/TMS
402, Section 3.3.3.4, splices. Modify items (b) and (c)
of Section 3.3.3.4 as follows:
3.3.3.4 (b). A welded splice
shall have the bars butted and welded to develop at least
125 percent of the yield strength, y, of
the bar in tension or compression, as required. Welded splices
shall be of ASTM A 706 steel reinforcement. Welded splices
shall not be permitted in plastic hinge zones of intermediate
or special reinforced walls or special moment frames of
masonry.
3.3.3.4 (c). Mechanical splices
shall be classified as Type 1 or 2 according to
Section 21.2.6.1 of ACI 318. Type 1 mechanical splices
shall not be used within a plastic hinge zone or within
a beam-column joint of intermediate or special reinforced
masonry shear walls or special moment frames. Type 2 mechanical
splices are permitted in any location within a member.
2108.4 ACI 530/ASCE 5/TMS
402, Section 3.3.3.5, maximum areas of flexural tensile reinforcement.
Add the following text to Section 3.3.3.5:
3.3.3.5.5 For special prestressed
masonry shear walls, strain in all prestressing steel shall
be computed to be compatible with a strain in the extreme
tension reinforcement equal to five times the strain associated
with the reinforcement yield stress, fy. The
calculation of the maximum reinforcement shall consider
forces in the prestressing steel that correspond to these
calculated strains.
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