# Corbel For Mac

Category | Humanist sans-serif |
---|---|

Designer(s) | Jeremy Tankard |

Foundry | Microsoft |

License | Proprietary |

**Corbel** is a humanistsans-seriftypeface designed by Jeremy Tankard for Microsoft and released in 2005. It is part of the ClearType Font Collection, a suite of fonts from various designers released with Windows Vista. All start with the letter *C* to reflect that they were designed to work well with Microsoft's ClearType text rendering system, a text rendering engine designed to make text clearer to read on LCD monitors. The other fonts in the same group are Calibri, Cambria, Candara, Consolas and Constantia.

Phone - 1-877-550-0600. Email - [email protected] 2510 Stanley Gault Parkway Louisville, KY 40223. Corbel brackets are beak-shaped, prominent on top where they meet the surface they will support, tapering in an arch to the wall below. The name is derived from a Latin cognate for raven and the. Corbel projects. Feel free to experiment, improve on the design or customize the technique to make your corbels suit the project at hand! This particular corbel project was designed to be used with 1”x10” or 1”x12”shelves. I have made available the ready-to-carve Corbel Project (mpc file).

## Design[edit]

In a blurb for its use, Corbel was described as 'designed to give an uncluttered, clean appearance on screen. The letter forms are open with soft, flowing curves. It is legible and clear at small sizes. At larger sizes the detailing and style of the shapes is more apparent.' The italic style is a true italic, with influences from serif fonts and calligraphy, with many letters gaining a tail pointing to the right. Many aspects of its design are similar to Calibri and Candara, which are also humanist sans-serif designs; like them it is slightly more condensed than average. Font designer Raph Levien, reviewing it for *Typographica*, described it as similar to Frutiger.^{[1]} Tankard described his aims in the family's design: “I wanted to move away from theround i-dot sans fonts we've seen a lot of recently. Less cuddly, more assertive. I wanted the italic to be expressive, not a sloped roman.'^{[2]}

Corbel by default renders numbers as text figures (*old style* or *lowercase* numerals), which are preferred for integrating figures into running text. This is an uncommon choice in sans-serif faces, especially those designed for display on a screen, but several of the other ClearType fonts also make this the default option; lining figures can be suggested using an OpenType stylistic alternates menu or CSS`font-variant-numeric:lining-nums`

. Text figures are also found in Microsoft's serif Georgia typeface.

## Releases[edit]

It is distributed with Microsoft Excel Viewer, Microsoft PowerPoint Viewer,^{[3]}^{[4]} the Microsoft Office Compatibility Pack^{[5]} for Microsoft Windows and the Open XML File Format Converter for Mac.^{[6]}

For use in other operating systems, such as GNU/Linux, cross-platform use and web use it is not available as a freeware and is licensed and sold by Ascender.

## References[edit]

**^**Levien, Raph. 'Microsoft's ClearType Font Collection: A Fair and Balanced Review'.*Typographica*. Retrieved 24 November 2014.**^***Now read this: the Microsoft ClearType font collection*. Redmond: Microsoft Corporation. 2004. pp. 36-42 etc.**^**'Download Excel Viewer from Official Microsoft Download Center'. Microsoft.**^**'Download PowerPoint Viewer from Official Microsoft Download Center'. Microsoft.**^**'Download Microsoft Office Compatibility Pack for Word, Excel, and PowerPoint File Formats from Official Microsoft Download Center'. Microsoft.**^**'Download Open XML File Format Converter for Mac 1.2.1 from Official Microsoft Download Center'. Microsoft.

## External links[edit]

Wikimedia Commons has media related to .Corbel |

- Microsoft Cleartype Font Collection at Microsoft Typography
- Van Wagener, Anne (2005-02-18). 'The Next Big Thing in Online Type'. Poynter Online. Retrieved 2016-02-17.Cite has empty unknown parameters:
`curly=`

and`coauthors=`

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**Introduction**

Corbel is a short structural element that cantilevers out from column/wall to support load. Generally, the corbel is casted monolithically with column/wall.

There are several typical modes of failure in the corbel. The most common of which are yielding of the tension tie, failure of the end anchorages of the tension tie, either under the load point or in the column, failure of the compression strut by crushing or shearing, and local failures under the bearing plate.

The following figures shows the failure mode of corbel

**Design of Corbel**

The corbel must be designed to resist simultaneously *Vu*, a factored moment *Mu* and a factored horizontal tensile force *Nuc*. ACI Code Section 11.8 requires corbels having *a/d* between 1 and 2 to designed using Appendix A, strut-and-tie models, where *a* is the distance from the load to the face of column and *d* is the depth of the corbel below the tie, measured at the face of the column. Corbels having *a/d *less than or equal 1 may be designed using either strut-and-tie models or traditional ACI designed method, Section 11.8. This paper presents Corbels design according to traditional ACI method.

**ACI Design Method**

**Shear Design of Corbel**

To avoid the crack that occurs in the interface of the corbel and the column we must provide the shear friction reinforcement perpendicular with the cracks direction. We use coefficient of friction μ to transform the horizontal resisting force into vertical resisting force.

The nominal shear strength of shear reinforcement can be determined using equations below

*V _{n} = A_{vf} f_{y} μ *for vertical shear friction reinforcement, and

*V _{n} = A_{vf} f_{y} (μ *sin

*α*cos

_{f}+*α*for inclined shear reinforcement

_{f})where

*V _{n}* : nominal shear strength of shear friction reinforcement

*A _{vf}* : area of shear friction reinforcement

*f _{y}* : yield strength of shear friction reinforcement

*μ* : coefficient of friction

Method | Coefficient of Friction, μ |

Concrete cast monolithic | 1.4λ |

Concrete placed against roughened hardened concrete | 1.0λ |

Concrete placed against unroughened hardened concrete | 0.6λ |

Concrete anchored to structural steel | 0.7λ |

The value of λ is 1.0 for normal weight concrete, 0.85 for sand light weight concrete and 0.75 for all light weight concrete.

The maximum nominal shear force, *Vn* shall not exceed the smallest of 0.2 fc’ b_{w }d and 5.5 b_{w} d, where

fc’ : compression strength of concrete (MPa)

b_{w }: width of corbel section (mm)

d : effective depth of corbel (mm)

**Flexural Design of Corbel**

The corbel is designed to resist ultimate flexural moment result from the supported beam reaction, *Vu* and horizontal force from creep and shrinkage, *Nu*c. The minimum value of *Nuc* is 0.2 *Vu* and not greater than *Vu*.

**Tension Reinforcement**

The ultimate horizontal force, Nuc shall be resisted by tension reinforcement as follow

*A _{n }= N_{uc }/ ϕf_{y}*

Where:

*A _{n}* : area of tension reinforcement

*N _{uc}* : ultimate horizontal force at corbel

*f _{y}* : yield strength of shear friction reinforcement

*ϕ* : strength reduction factor

**Flexural Reinforcement**

The ultimate flexure moment, *Mu* is

*Mu = Vu a _{v} + Nuc (h – d)*

Where:

*Mu* : ultimate flexure moment

*Vu* : ultimate shear force

*a _{v}* : distance from Vu to the face of column

*Nuc* : ultimate horizontal force at corbel

*h* : height of corbel

*d* : effective depth of corbel

*Mu ≤ ϕ A _{f } f_{y } (d-a/2)* where

*a = A _{f} f_{y} / 0.85f’_{c} b *

From the equation above, area of flexural reinforcement, *A _{f}*can be determined using trial and error. As first trial,

*(d – a/2)*can be assumed

*0.9d*so that

*A _{f} ≥ Mu / ϕ f_{y }(0.9d) *

For practical reason, the value of *(d – a/2)* can be used *0.85d*

*A _{f} ≥ Mu / ϕ f_{y }(0.85d) *

After finding *A _{vf}*,

*A*, and

_{n}*A*, we must then calculate the primary tension reinforcement

_{f}*A*from the larger of

_{sc}*A*and

_{f }+ A_{n}*2A*

_{vf}/3 + A_{n}**Reinforcement Limits**

The primary steel reinforcement at corbel design,

*A _{sc}* shall not be less than

*0.04 f*

_{c}‘ bw d /f_{y}The horizontal closed stirrups,

*A _{h}* shall not be less than

*0.5 (A*

_{sc}– A_{n})**Distribution of Corbel Reinforcement**

The horizontal closed stirrups, Ah shall be distributed uniformly within (2/3) d adjacent to primary tension reinforcement.

**Design Procedure**

**Step 1. Find factored shear V _{u} and tensile force N_{uc}**

*If N _{uc} is not specified, use a minimum value of N_{uc} = 0.2 V_{u}*(ACI 11.9.3.4)

Compute nominal values of shear and tensile force

V_{n} = V_{u} / 0.75 ; N_{nc} = N_{uc} / 0.75

If V_{n} > 0.2 fc’ b d OR

V_{n} > 5.5 b d then section size is inadequate (ACI 11.9.3.2)

**Step 2. Compute shear-friction reinforcement (ACI 11.7.4.1)**

*A _{vf} = V_{n} /μ f_{y}*

**Step 3. Calculate required flexural reinforcement (11.9.3.3)**

*Mu = Vu a _{v} + Nuc (h – d)*

*A _{f} = Mu / ϕ f_{y }(jd) (assume jd = 0.85d)*

**Step 4. Reinforcement to carry tensile force (ACI 11.9.3.4)**

*A _{n }= N_{uc }/ ϕf_{y}*

**Step 5. Required main flexural steel (A_{sc}) is given by (ACI 11.9.3.5 and 11.9.5)**

the larger of

*A _{f }+ A_{n}* and

*2A*

_{vf}/3 + A_{n}**Step 6. Provide closed horizontal stirrups (ACI 11.9.4):**

*A _{h} = 0.5 (A_{sc} – A_{n})*

Ensure adequate detailing (ACI 11.9.6 & 11.9.7)

**Example**

**Corbel Geometri**

Width of corbel, b = 300 mm

Total thickness of corbel, h = 500 mm

## Corbel For Mantel

Depth to main reinforcement, d = 450 mm

**Material Properties**

Yield strength of reinforcement, fy = 415 Mpa

Compressive strength of concrete, fc’ = 35 Mpa

## Corbel Font For Mac

Normal weight concrete, λ = 1

Coefficient friction, μ = 1.4 x λ = 1.4

**Design Load Data**

Factored vertical load, Vu = 370 kN

Distance from face to column, a = 100 mm

Horizontal force, Nu = 75 kN

Strength reduction factor, ϕ = 0.75

**Design Procedure**

**Step 1. Find factored shear V _{u} and tensile force N_{uc}**

V_{u} = 370 kN

N_{uc_min} = 0.2 x 370 = 74 kN

N_{uc_act} = the larger of 74 kN and 75 kN

= 75 kN

Compute nominal value of shear and tensile force

V_{n} = 370 / 0.75 = 493.33 kN

N_{nc} = N_{uc} / 0.75 = 100 kN

Check section

0.2 x fc’x b x d = 945.0 kN > 493.33 kN

5.5 x b x d = 742.5 kN > 493.33 kN

Section is OK

**Step 2. Compute shear-friction reinforcement (ACI 11.7.4.1)**

*A _{vf} = V_{n} /μ f_{y = }*

*493.33 / (1.4×415) = 849.11 mm*

^{2}**Step 3. Calculate required flexural reinforcement (11.9.3.3)**

*Mu = Vu a _{v} + Nuc (h – d) = 370 x 1000 x 100 + 75 x 1000 (500-450) *

## Corbel Maconnerie

*A _{f} = Mu / ϕ f_{y }(0.85d) =342.28 mm^{2}*

**Step 4. Reinforcement to carry tensile force (ACI 11.9.3.4)**

*A _{n }= N_{uc }/ ϕf_{y = }*

*75×1000 / 0.75×415 =240.96*

*mm*^{2}**Step 5. Required main flexural steel (A_{sc}) is given by (ACI 11.9.3.5 and 11.9.5)**

*A _{f }+ A_{n}* = 342.28 + 240.96 = 583.25

*mm*

^{2}*2A _{vf}/3 + A_{n }*= 2/3 849.11 + 240.96 = 807.04

*mm*

^{2}*A _{sc} = 807.04 mm^{2}*

Use 3 dia 20 bars

*A _{sc_prov }= 3 x 314 = 942 mm^{2}*

**Step 6. Provide closed horizontal stirrups (ACI 11.9.4):**

* A _{h} = 0.5 (A_{sc} – A_{n})= 0.5(807.04 – 240.96) =283.04 mm^{2}*

Use 3 dia 8 bars

*A _{h_prov}=2×3×50 = 300 mm^{2}*

* S _{h} = (2×d/3)/3 = (2×450/3)/3 = 100 mm*

**Detailed reinforcement**