TM 5-809-3/NAVFAC DM-2.9/AFM 88-3, Chap. 3
forces. Because joints and connections directly affect the integrity of the structure, their design and
fabrication must be adequate for the functions intended. In designing and detailing, it must be recognized that
the lateral forces are not static, as assumed for convenience, but dynamic and to a great extent unpredictable.
Because of this, it is important to provide the minimum connections required below even when they are not
specifically required for design loading. In seismic zones 1 through 4 the minimum connection requirements
given in TM 5-809-10/NAVFAC P-355/AFM 88-3, Chapter 13 must also be satisfied. When the design
forces on joints and connections between lateral force resisting elements are due to wind, the minimum
criteria given in TM 5-809-2/AFM 88-3, Chapter 2, will be followed.
a. Forces to be considered. Forces to be considered in the design of joints and connections are gravity
loads; temporary erection loads; differential settlement; horizontal loads normal to the wall; horizontal loads
parallel to the wall; and creep, shrinkage, and thermal forces; separately or combined as applicable. Bond
beams at roof or floor diaphragm levels must have the reinforcement continuous through control joints to
resist the tensile and compressive chord stresses induced by the diaphragm beam action. The connections
between the diaphragm and chord (bond beam) members must be capable of resisting the stresses induced
by external loadings.
b. Joints and connections. Joints and connections may be made by welding steel reinforcement to
structural steel members, by bolting, by dowels, by transfer of tensile or compressive stresses by bond of
reinforcing bars, or by use of key-type devices. The transfer of shear may be accomplished by using
reinforcing steel extended as dowels coupled with cast-in-place concrete placed between roughened concrete
interfaces or by mechanical devices such as embedded plates or shapes. The entire shear loading should be
transferred through one type of device, even though a combination of devices may be available at the joint
or support being considered. Maximum spacing of dowels or bolts, for load transfer between elements, will
not exceed four feet. All significant combinations of loadings will be considered, and the joints and
connections will be designed for forces consistent with all reasonable combinations of loadings as given in
TM 5-809-1/AFM 88-3, Chapter 1. Details of the connections will be based on rational analysis in accordance
with established principles of mechanics.
c. Allowable tension and shear on bolts. The allowable loads for plate, headed, and bent bar anchor bolts
embedded in masonry will be determined in accordance with the criteria in ACT 530/ASCE 6. Tables 5-12,
5-13 and 5-14 were developed using that criteria.
5-12
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