Concrete block rebar full#
Concrete block rebar series#

Using the grout demonstration panel option in Specification for Masonry Structures (ref. Approval should be obtained before adjusting the slump outside the requirements. This slump may be adjusted under certain conditions such as hot or cold weather installation, low absorption units or other project specific conditions. To prevent bridging, grout slump is required to be between 8 and 11 in. This is because large protrusions can restrict the flow of grout, which will tend to bridge at these locations potentially causing incomplete filling of the grout space. (13 mm) into the grout space must be removed (ref. In cases such as those, open end or open core units (see Figure 3) should be considered as there is no space between end webs with these types of units.Ĭare should be taken to prevent excess mortar from extruding into the grout space.

Concrete block rebar full#

In certain instances, full head joint mortaring should also be considered when solid grouting since it is unlikely that grout will fill the space between head joints that are only mortared the width of the face shell, i.e., when penetration resistance is a concern such as storm shelters and prison walls. If the wall will be solidly grouted, the cross webs need not be mortared since the grout flows laterally, filling all spaces. If the wall will be partially grouted, those webs adjacent to the cores to be grouted are mortared to confine the grout flow. Head and bed joints must be filled with mortar for the full thickness of the face shell.

Concrete block rebar series#

When walls will be grouted, concrete masonry units must be laid up so that vertical cores are aligned to form an unobstructed, continuous series of vertical spaces within the wall. This TEK covers methods for laying the units, placing steel reinforcement and grouting.įigure 1 shows the basic components of a typical reinforced concrete masonry wall. Specifications for grout, sampling and testing procedures, and information on admixtures are covered in NCMA TEK 9-4A, Grout for Concrete Masonry (ref. If vertical reinforcement is spaced close together and/or there are a significant number of bond beams within the wall, it may be faster and more economical to solidly grout the wall. When all cores, with or without reinforcement, are grouted, the wall is considered solidly grouted. In partially grouted walls, grout is placed only in wall spaces containing steel reinforcement. In reinforced masonry, grout bonds the masonry units and reinforcing steel so that they act together to resist imposed loads. Grout may also be used to stabilize screen walls and other landscape elements. Grout may also be added to increase the wall’s fire rating, acoustic effectiveness termite resistance, blast resistance, heat capacity or anchorage capabilities. It is also used to fill bond beams and occasionally to fill the collar joint of a multi-wythe wall. Grout is used to give added strength to both reinforced and unreinforced concrete masonry walls by grouting either some or all of the cores.

Grout is a mixture of: cementitious material (usually portland cement) aggregate enough water to cause the mixture to flow readily and without segregation into cores or cavities in the masonry and sometimes admixtures. The industry is experiencing fast-paced advances in grouting procedures and materials as building codes allow new opportunities to explore means and methods for constructing grouted masonry walls. Number of concrete blocks needed = 90 concrete blocksīy multiplying the core volume of a single concrete block by the number of concrete blocks needed to build the wall, we can then find the fill volume, as shown below:įill volume = core volume per concrete block × number of concrete blocks neededįill volume = 0.006424 m³ × 90 concrete blocksįrom our calculations above, we can now say that we need around 0.5782 m³ of concrete or mortar to fill the concrete blocks that we will use to construct our wall.Grouted concrete masonry construction offers design flexibility through the use of partially or fully grouted walls, whether plain or reinforced. Number of concrete blocks needed = 7.2 m² / 0.08 m² Number of concrete blocks needed = (3.0 m × 2.4 m) / (0.4 m × 0.2 m) Number of concrete blocks needed = (wall width × wall height) / (block width × block height) Now that we have all the details we need, we need to divide the total wall area by the area of a concrete block to find the number of blocks our wall needs:

The core volume of a standard size 6-inch concrete block is approximately 392 in³ or 0.006424 m³. As a sample calculation, let us consider building a 3.0-meter wide and 2.4 meter high wall using 6-inch thick standard 8' × 16' (20 cm × 40 cm) concrete hollow blocks.