The use of empirical design of masonry shall be limited as noted in Section 5.1.2 of TMS 402/ACI 530/ASCE 5. The use of dry-stacked, surface-bonded masonry shall be prohibited in Risk Category IV structures. In buildings that exceed one or more of the limitations of Section 5.1.2 of TMS 402/ACI 530/ASCE 5, masonry shall be designed in accordance with the engineered design provisions of Section 2101.2.1, 2101.2.2 or 2101.2.3 or the foundation wall provisions of Section 1807.1.5.
Dry-stacked, surface-bonded concrete masonry walls shall be of adequate strength and proportions to support all superimposed loads without exceeding the allowable stresses listed in Table 2109.2.1. Allowable stresses not specified in Table 2109.2.1 shall comply with the requirements of TMS 402/ACI 530/ASCE 5.
|DESCRIPTION||MAXIMUM ALLOWABLE STRESS (psi)|
|Compression standard block||45|
The modulus of rupture shall be determined by the equation:
|f r = 3 PLs /2 Sw (St2)||(Equation 21-2)|
|Sw||=||Width of the test specimen measured parallel to the loading cylinder, inches (mm).|
|fr||=||Modulus of rupture, psi (MPa).|
|Ls||=||Distance between supports, inches (mm).|
|St||=||Thickness of the test specimen measured parallel to the direction of load, inches (mm).|
|P||=||The applied load at failure, pounds (N).|