What are the design specifications of masonry wall?
According to the ACI code and IBC 2000, εmu shall be 0.0035 for clay masonry and 0.002 for concrete masonry. In wall design for out-of-plane loads according to both the codes, the required moment due to lateral loads, eccentricity of axial load and lateral deformation are assumed maximum at mid-height of the wall.
How tall can a 8 CMU wall be?
It is not uncommon to create designs with an h/t from 32 to 50. That could produce wall heights of up to 33 feet for walls built with 8-inch concrete masonry units (CMU), 41 feet for 10-inch CMU, and 50 feet for 12-inch CMU. Regionally, 14- and 16-inch CMU are available, which extend possible wall heights even further.
What is empirical design of masonry?
Empirical design is a procedure of proportioning and sizing unreinforced masonry elements based on known historical performance for a given application. It has proven to be an expedient design method for typical loadbearing structures subjected to relatively small wind loads and located in areas of low seismic risk.
What are CMU walls?
A concrete masonry unit (CMU) is a standard-size rectangular block used in building construction. CMUs are some of the most versatile building products available because of the wide variety of appearances that can be achieved using them.
How are CMU walls made?
Concrete masonry units (CMU) are made from a mixture of portland cement and aggregates under controlled conditions. The units can be made to various dimensions, but typically have face dimensions of 8 inches high by 16 inches wide (nominal).
How do you measure CMU?
Concrete Masonry Units (CMUs) are manufactured in a variety of sizes. They are identified by their depth – i.e. the thickness of the wall they create. For instance, a 6″ CMU is nominally 6″ deep while a 10″ CMU is nominally 10″ deep.
How high can a 6 CMU wall be?
The rule of thumb (and I say rule of thumb because there is not enough data given here for a qualified structural engineer to make a calculation) for a non-reinforced CMU wall is 20t. That results in a 10-foot high maximum for 6-inch CMU.
How tall can a 6 CMU wall be?
Is code for brick masonry design?
The code refers to IS: 4326 for strengthening unreinforced masonry building for seismic resistance and does not provide any calculation for the design of reinforcement.
Is CMU load bearing?
Concrete masonry units act as bearing wall supports for residential homes and buildings, supporting vertical loads such as floor joists, arches, vaults and roof rafters, and horizontal loads like wind and seismic activity.
Is brick a CMU?
Brick—A solid or hollow manufactured masonry unit of either concrete, clay or stone. Concrete block—A hollow or solid concrete masonry unit. Larger in size than a concrete brick. Concrete brick—A concrete hollow or solid unit smaller in size than a concrete block.
What does CMU stand for?
CMU- See Concrete Masonry Unit. Collar Joint- The vertical, longitudinal joint between wythes of masonry. Column- A member with a ratio of height-to-least-lateral dimension of 3 or greater used primarily to support axial compressive load.
What is Em and as in CMU?
Em = The modulus of elasticity of the masonry, psi. Em = 1000f’ m for CMU. f’m = The compressive strength of masonry, psi. As = The cross-sectional area of reinforcing steel, in . 2 b.
What are the STC ratings for CMU walls?
Calculated STC Ratings for CMU Walls* Nominal Unit Thickness Density, pcf STC Rating Hollow Unit Grout-Filled 4” 95 105 115 125 135 44 44 44 45 45 46 46 47 47 47 6” 95 105 115 125 135 44 45 45 46 46 50 50 51 51 52 8” 95 105 115 125 135 46 46 47 47 48 53 54 55 55 56 10” 95 105 115 125 135 47 48 48 49 50 53 54 55 55 56 12”
What is the best size of reinforcing steel for CMU walls?
The most commonly used, and preferred, reinforcing steel bar sizes in CMU walls are Nos. 4, 5 and 6. W hen the design requires the use of larger bars, the bar size will not exceed No. 6 bars in 6-inch CMU walls, No. 7 bars in 8-inch CMU walls and No. 8 bars in 10-inch and 12-inch CMU walls.