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  LOYOLA  MARYMOUNT  UNIVERSITY    

 

The Renewal of the Tin Shed Building

Santa Barbara, CA

Final  draft  design  report  

 

 

 

Loyola Marymount University

Bader Alghunaim

November 30, 2015

Civil 305: Structural Analysis

 

 

 

 

 

 

 

 

 

 

                     

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LOYOLA  MARYMOUNT  UNIVERSITY    

 

Department  of  Civil  Engineering  and  Environmental  Science  

Loyola  Marymount  University    

1  LMU  Drive    

Los  Angeles,  CA  90045  

 

Dear  Dr.  Manoogian,    

 

Final  Report  of  the  Tin  Shed  Building  

I  have  pleasure  in  submitting  the  enclosed  final  report  of  my  structural  project.  This  report  satisfies  the  requirements  and  instructions  you  provided.  Enclosed  is  the  primary  design  report  and  recommendations  for  the  project.  

Included  in  this  report  is:  background  information  on  Santa  Barbara’s  building  codes,  the  purpose  of  the  building,  the  building’s  design  loads,  the  girder  and  column  layout,  the  tributary  load  maps,  and  the  beam  and  column  selections.    

It  has  been  a  great  experience  to  work  on  this  project.  I  am  glad  to  say  that  my  structural  analysis  of  the  Tin  Shed  building  fulfills  the  reports  requirements.  Please  review  this  report  and  contact  me  with  your  questions,  comments  and  concerns  so  as  to  proceed  to  the  final  stage  of  the  construction  of  the  Tin  Shed.  

 

Sincerely,  

 

Bader  Alghunaim  

 

 

 

Civil  Engineering  Associate    

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Table of Contents  

1. Introduction 1.1. Background……………………………………………………….4

1.2. Purpose…………………………………………………………….4

2. Design Loads 2.1. Assumptions……………………………………………………….8

2.2. Load Table………………………………………………………...10

2.3. Worst Case LRFD Load Combination Table………..…………….10

2.4. Material Selection………………………………………………….10

3. Tributary Loads 3.1. Column and Girder Layout………………………………...……….11

3.2. Tributary Load Maps……………………………………………….12

3.3. Tributary Load Tables…………………………………………..….15

4. Beam Selections 4.1. Beam Selections For EW Girders………………………………….18

4.2. Beam Selections for NS Girders……………………………………19

4.3. Column Selections……………………………….………………….20

4.4. Column and Girder Layout with Beam Selections………………….21 5. Appendix

5.1. Calculations……………………………….…………………..…….22

5.2. LRFD Load Combination Table………………….………………….24 6. References……………………………….…………………………….25

 

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1. Introduction: 1.1. Background: The new tin shed will be a redesigned version of the previous Engineering Design Center. This new structure will consist mostly of a single floor for machining and material processing, as well as a small second story for light storage. This new design center will replace the previous one located at: 1230 Garden Street, Santa Barbara, CA, 93101

 

Figure  1:  Geographic  map  of  the  location  of  the  Engineering  Design  Center  

The new design center will be built with the dimensions 100’ W x 40’L x 30’H, identical to the previous design center dimensions. The newly added second floor will be 50’W x 40’L x 12’H, and will be situated above the machining area. The new design center will be built in Santa Barbara, therefore industry code for standard rain, wind and seismic conditions should be applied. An emphasis on earthquake conditions should be taken into account during construction, since the location is prone to earthquakes. Snow conditions should be ignored, as the area is not prone to snowfall.

1.2. Purpose:

The new design of the Engineering Design Center, nicknamed the “Tin Shed” by students, will create a more student friendly environment with a storage space on a second floor above the machining area. This storage space on the second floor creates a space for the students to work and utilize the machinery in place. The original design did not account for a separate floor for storage and was therefore not as efficiently organized. The new design center will be divided into

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three sections. The first half of the first floor will be the student work area, the second half of the first floor will be the machining area, and the third section will be the second floor storage area. Figures 2, 3, 4, 5, 6, and 7 show the skeletal drawing, exterior views, and floor plans of the building.

 

Figure  2:  Skeletal  Drawing  for  new  design  

 

Figure  3:  Top  view  of  new  design  

   

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Figure  4:  Exterior  view  of  new  design  

 

Figure  5:  Exterior  view  with  wall  removed  

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Figure  6:  2nd  Floor  floorplan  

 

Figure  7:  1st  Floor  floorplan  

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2. Design Loads: 2.1. Assumptions

The location for the New Design Center is Santa Barbara. The primary sources for the loads on the building are the IBC 2012 and ASCE 7-10. These sources will help determine the minimum design loads caused by the wind, seismic, rain, dead, and live loads acting on the building. The Design Center will be designed as a Risk Category 3, fully exposed, Exposure Category B, Terrain Category B, fully enclosed building. The loads applied to each floor are uniform.

Dead Loads (D)

The dead load assumed for the roof is 60 psf. This assumption was made after calculating the weight of the roof itself and adding it to the weight of the ceiling. Assuming a 4inch thick concrete slab (with 9.6 pounds per square foot per inch of thickness), a steel deck, steel joists, insulation, and a bituminous smooth surface membrane; the roof is calculated to weigh 50.9psf (ASCE 7-10, C3-1). The remaining dead loads are from the ceiling. Assuming a suspended steel channel system, acoustical tile, lights and ducting, the remaining dead load is calculated to 8 psf (ASCE 7-10, C3-1). The total dead load is calculated to be 58.9 psf. This number was then rounded up to 60psf. See Appendix for calculations.

The dead load assumed for the 2nd floor is 60 psf. This assumption was made after calculating the weight of the 2nd floor itself and adding it to the weight of the ceiling. Assuming a 4inch thick concrete slab (with 9.6 pounds per square foot per inch of thickness), a steel deck, steel joists, carpeting and padding; the 2nd floor is calculated to weigh 49.4psf (ASCE 7-10, C3-1). The remaining dead loads are from the ceiling. Assuming a suspended steel channel system, acoustical tile, lights and ducting, the remaining dead load is calculated to 8 psf (ASCE 7-10, C3-1). The total dead load is calculated to be 57.4 psf. This number was then rounded up to 60psf. See Appendix for calculations.

Live Loads (L)

The live load for the 2nd floor is assumed to be 125psf. This is the industry standard loading for light storage areas (IBC 2012, Table 4-1). The live load for the roof is assumed to be 0psf. This is under the assumption that there will be no consistent live loads on the roof.

Roof Live Loads (𝑳𝑹)

The roof live load is assumed to be 20psf. This is the industry standard minimum design load for all roofs (IBC 2012).

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Rain Loads (R)

The flow rate is dependent of the area of the building and the rain intensity (i), which was taken form Figure 1611.1 to be 3 in/hr. The total area (A) of the roof is 4000𝑓𝑡!. Implementing a two-drain system, the area served by each drain will then be 2000 𝑓𝑡!. Therefore flow rate (Q) of rain was calculated to be 62.4 gpm. Assuming 4 inch drain diameters and using table 2.5 (Mike 11), dh=1’’ A ds of 2’’ was then assumed and the rain load was calculated to be 15.6psf. See Appendix for calculations.

Rain loads on the 2nd floor are assumed to be 0psf since the design center is a fully enclosed building.

Snow Loads (S)

Snow Loads on the roof were calculated to be 0 psf. For snow loads, the snow importance factor 𝐼!, exposure factor 𝐶!, thermal factor 𝐶!, and ground snow load 𝑝! are all required to calculate snow load (S). The design center is assumed to be a risk category 3 building and will therefore have an 𝐼!of 1.1 (ASCE 7-10 1.5-2). It is also assumed to be a Category B fully exposed building and will therefore have a 𝐶!of 0.9 (ASCE 7-10, Table 7-2). Since the structure is heated and is not a greenhouse, its 𝐶!is 1.0 (ASCE 7-10, Table 7-3). As for the ground snow loads, since Santa Barbara has an elevation of 3ft above sea level (far below 1500 ft) 𝑝!=0 (IBC 2012). When all of these factors are taken into consideration the assumed snow load is calculated to be 0psf. Calculations in Appendix

Snow loads on the 2nd floor are assumed to be 0psf since the design center is a fully enclosed building.

Wind Loads (W)

The wind loads were calculated to be 25.8psf. In order to calculate this load the wind speed of Santa Barbara was determined to be 115mph (IBC 2012, Figure 1609B). The topographical factor (𝑘!") was assumed to be 1.0 since the design center was built on flat land. And k1 and k2 were taken from ASCE 27.3.1 to be 0.6 and 0.7 respectively. With all of these assumptions taken into consideration, the calculated wind load was 25.8psf.

Wind loads on the 2nd floor are assumed to be 0psf since the design center is a fully enclosed building.

Earthquake Loads (E)

The seismic/earthquake loads were assumed to be 10psf. These values were given.

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2.2. Load Table

Table 1, below, presents the calculated loads given by dead (D), live (L), live roof (𝐿!), rain(R), snow (S), wind (W), and seismic stresses (E). Calculations can be found in the Appendix (section 5.1).

Table  1:  Load  Table  

Load   2nd  Floor  (psf)   Roof  (psf)   Source  D   60   60   ASCE  7-­‐10,  Table  C3-­‐

1  L   125   0   IBC  2012,  pg19,  

Table  4-­‐1  Lr   0   20   IBC  2012,  pg  333  R   0   15.6   IBC  2012,  pg  360  S   0   0   ASCE  7-­‐10,  29-­‐34  W   0   25.8  

 ASCE  7-­‐10,  27.3.1,pg  

261  IBC  Figure  1609B  pg  

351  E   10   10   Given  

2.3. Worst Case LRFD Load Combination Table

Table 2, below, uses the highest valued combination of the values in Table 1 to predict the LRFD worst-case load combination for both the roof and 2nd floor. Calculations can be found in the Appendix (section 5.2).

 

Table  2:  Worst  Case  Scenario  LRFD  Table  

Floor   Design  Load  (psf)  Roof   116.9  

2nd  Floor   272  

2.4. Material Selection

The material used for this building are Wide-flange Steel beams, and columns made out of Structural Steel, ASTM A529 Grade 50, Yield Stress of 50,000 lb/in2

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3. Tributary Loads 3.1. Column and Girder Layout

The column and girder layouts for the roof and 2nd floor can be seen in frame format in Figures 8 and 9, respectively. Each column is 1ft by 1ft. Girders in the North-South direction are 20 ft long, and girders in the East-West direction are 25 ft long.

 

Figure  8:  Frame  of  Roof  

 

Figure  9:  Frame  of  2nd  Floor  

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3.2. Tributary Load Maps This section contains the tributary load maps. Figures 10 and 11 show the tributary loads on the EW and NS girders on the roof respectively. Figure 12 shows the tributary loads on the columns of the roof. The 2nd floor tributary girder load maps are shown in figures 13 and 14, and the 2nd floor tributary load map for the columns is shown in figure 15.

 

Figure  10:Tributary  Load  For  Girders  on  Roof  East-­‐West  

   

 

Figure  11:Tributary  Loads  For  Girders  on  Roof  North-­‐South  

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Figure  12:Tributary  Loads  For  Columns  on  Roof  

 

 

Figure  13:  Tributary  Loads  For  Girders  on  2nd  Floor  East-­‐West  

 

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Figure  14:Tributary  Loads  For  Girders  on  2nd  Floor  North-­‐South  

 

 

Figure  15:  Tributary  Loads  For  Columns  on  2nd  Floor  

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3.3. Tributary Load Tables

The implemented design load combination for the 272psf for the 2nd floor and 116.9psf for the roof. The implemented load combinations take into account the live, dead, snow, wind, earthquake and rain loads acting on the building. Tables 3 and 4 depict the tributary load effect on the EW girders on the roof and second floor respectively. Tables 5 and 6 show the tributary load effect on the NS girders on the roof and second floor respectively. These four tables show the calculated weight and moment due to the tributary load on each girder. Table 7 shows the force on each column due to the tributary loads.

Table  3:  Tributary  Loads  For  EW  Girders  on  Roof  

 

Design  Load  

 

Length   Weight   Moment  

Girder   (kip/ft^2)  

 

(ft)   (kips/ft)   (kips-­‐ft)  

A1B1   0.1169  

 

20   1.46   73.1  

A2B2   0.1169  

 

20   2.92   146  

A3B3   0.1169  

 

20   2.92   146  

A4B4   0.1169  

 

20   2.92   146  

A5B5   0.1169  

 

20   1.46   73.1  

B1C1   0.1169  

 

20   1.46   73.1  

B2C2   0.1169  

 

20   2.92   146  

B3C3   0.1169  

 

20   2.92   146  

B4C4   0.1169  

 

20   2.92   146  

B5C5   0.1169  

 

20   1.46   73.1  

 

 

 

 

 

   

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Table  4:  Tributary  Loads  for  EW  Girders  on  2nd  Floor  

 

Design  Load   Length   Weight   Moment  

Girder   (kip/ft^2)   (ft)   (kips/ft)   (kips-­‐ft)  

A1B1   0.272   20   3.4   170  

A2B2   0.272   20   6.8   340  

A3B3   0.272   20   3.4   170  

B1C1   0.272   20   3.4   170  

B2C2   0.272   20   6.8   340  

B3C3   0.272   20   3.4   170  

Table  5:  Tributary  Load  Table  for  NS  Girders  on  Roof  

 

  Design  Load   Length   Weight   Moment  

Girder     (kip/ft^2)   (ft)   (kips/ft)   (kips-­‐ft)  

A12     0.1169   25   1.169   91.3  

A23     0.1169   25   1.169   91.3  

A34     0.1169   25   1.169   91.3  

A45     0.1169   25   1.169   91.3  

B12     0.1169   25   2.338   183  

B23     0.1169   25   2.338   183  

B34     0.1169   25   2.338   183  

B45     0.1169   25   2.338   183  

C12     0.1169   25   1.169   91.3  

C23     0.1169   25   1.169   91.3  

C34     0.1169   25   1.169   91.3  

C45     0.1169   25   1.169   91.3  

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Table  6:  Tributary  Loads  for  NS  Girders  on  2nd  Floor  

 

Girder   Design  Load  

 

Length   Weight   Moment  

 

(kip/ft^2)  

 

(ft)   (kips/ft)   (kips-­‐ft)  

A12   0.272  

 

25   2.72   213  

A23   0.272  

 

25   2.72   213  

B12   0.272  

 

25   5.44   425  

B23   0.272  

 

25   5.44   425  

C12   0.272  

 

25   2.72   213  

C23   0.272  

 

25   2.72   213  

Table  7:  Tributary  Loads  on  Columns  

Columns   Pr  (kips)   Ps(kips)   Pt(kips)   Eff.  Length  (ft)  

A1   14.6   34   48.6   18  

A2   29.2   68   97.2   18  

A3   29.2   34   63.2   18  

A4   29.2   0   29.2   30  

A5   14.6   0   14.6   30  

B1   29.2   68   97.2   18  

B2   58.4   136   194.4   18  

B3   58.4   68   126.4   18  

B4   58.4   0   58.4   30  

B5   29.2   0   29.2   30  

C1   14.6   34   48.6   18  

C2   29.2   68   97.2   18  

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C3   29.2   34   63.2   18  

C4   29.2   0   29.2   30  

C5   14.6   0   14.6   30  

 

4. Beam Selection 4.1. Beam Selections for EW Girders

Using the calculated moments from the previous section, beams were selected for the EW girders based on the moment due to the tributary load acting on the beams. The beams were selected using the AISC Steel Manual, 14th edition. Tables 8 and 9 show the beams selected for each girder, on the roof and second floor respectively, as well its maximum bending moment, moment of inertia, and maximum displacement due to the load acting on it.

Table  8:  EW  Beam  Selection  Table  for  Roof  

Girder   Length  (ft)  

Weight  (kip/ft)  

Selection   Bending  Moment  (kips-­‐ft)  

E  (ksi)  

Moment  of  inertia  (in^4)  

Max  Displacement  

(in)  A1B1   20   1.169   W12  x  16   75.4   29000   103   1.76  A2B2   20   1.169   W14  x  26   151   29000   245   1.48  A3B3   20   1.169   W14  x  26   151   29000   245   1.48  A4B4   20   1.169   W14  x  26   151   29000   245   1.48  A5B5   20   2.338   W12  x  16   75.4   29000   103   1.76  B1C1   20   2.338   W12  x  16   75.4   29000   103   1.76  B2C2   20   2.338   W14  x  26   151   29000   245   1.48  B3C3   20   2.338   W14  x  26   151   29000   245   1.48  B4C4   20   1.169   W14  x  26   151   29000   245   1.48  B5C5   20   1.169   W12  x  16   75.4   29000   103   1.76  

Table  9:  EW  Beam  Selection  Table  for  2nd  Floor  

Girder   Length  (ft)  

Weight  (kip/ft)  

Selection   Bending  Moment  (kips-­‐ft)  

E  (ksi)  

Moment  of  inertia  (in^4)  

Max  Displacement  

(in)  A1B1   20   3.4   W14  x  30   177   29000   291   1.45  A2B2   20   6.8   W21  x  44   358   29000   843   1.00  A3B3   20   3.4   W14  x  30   177   29000   291   1.45  B1C1   20   3.4   W14  x  30   177   29000   291   1.45  B2C2   20   6.8   W21  x  44   358   29000   843   1.00  B3C3   20   3.4   W14  x  30   177   29000   291   1.45  

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4.2. Beam Selections for NS Girders

Using the calculated moments from the previous section, beams were selected for the NS girders based on the moment due to the tributary load acting on the beams. The beams were selected using the AISC Steel Manual, 14th edition. Tables 10 and 11 show the beams selected for each girder, on the roof and second floor respectively, as well its maximum bending moment, moment of inertia, and maximum displacement due to the load acting on it.

Table  10:  NS  Beam  Selection  Table  for  Roof  

Girder   Length  (ft)  

Weight  (kip/ft)  

Selection   Bending  Moment  (kips-­‐ft)  

E  (ksi)  

Moment  of  inertia  (in^4)  

Max  Displacement  

(in)  A12   25   1.169   W12  x  19   92.6   29000   130   2.73  A23   25   1.169   W12  x  19   92.6   29000   130   2.73  A34   25   1.169   W12  x  19   92.6   29000   130   2.73  A45   25   1.169   W12  x  19   92.6   29000   130   2.73  B12   25   2.338   W16  x  31   203   29000   375   1.89  B23   25   2.338   W16  x  31   203   29000   375   1.89  B34   25   2.338   W16  x  31   203   29000   375   1.89  B45   25   2.338   W16  x  31   203   29000   375   1.89  C12   25   1.169   W12  x  19   92.6   29000   130   2.73  C23   25   1.169   W12  x  19   92.6   29000   130   2.73  C34   25   1.169   W12  x  19   92.6   29000   130   2.73  C45   25   1.169   W12  x  19   92.6   29000   130   2.73  

Table  11:  NS  Beam  Selection  Table  for  2nd  Floor  

Girder   Length  (ft)  

Weight  (kip/ft)  

Selection   Bending  Moment  (kips-­‐ft)  

E  (ksi)  

Moment  of  inertia  (in^4)  

Max  Displacement  

(in)  A12   25   2.72   W18  x  35   249   29000   510   1.62  A23   25   2.72   W18  x  35   249   29000   510   1.62  B12   25   5.44   W21  x  55   473   29000   1330   1.24  B23   25   5.44   W21  x  55   473   29000   1330   1.24  C12   25   2.72   W18  x  35   249   29000   510   1.62  C23   25   2.72   W18  x  35   249   29000   510   1.62  

 

 

 

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4.3. Column Selections

Using the calculated forces from the previous section, columns were. The beams were selected using the AISC Steel Manual, 14th edition. Table 12 shows the selected columns.

Table  12:  Column  Selections    

Columns   Pr  (kips)   Ps(kips)   Pt(kips)   Eff.  Length  (ft)   Selection  

A1   14.6   34   48.6   18   W8  x  31  

A2   29.2   68   97.2   18   W8  x  31  

A3   29.2   34   63.2   18   W8  x  31  

A4   29.2   0   29.2   30   W8  x  31  

A5   14.6   0   14.6   30   W8  x  31  

B1   29.2   68   97.2   18   W8  x  31  

B2   58.4   136   194.4   18   W8  x  35  

B3   58.4   68   126.4   18   W8  x  31  

B4   58.4   0   58.4   30   W8  x  31  

B5   29.2   0   29.2   30   W8  x  31  

C1   14.6   34   48.6   18   W8  x  31  

C2   29.2   68   97.2   18   W8  x  31  

C3   29.2   34   63.2   18   W8  x  31  

C4   29.2   0   29.2   30   W8  x  31  

C5   14.6   0   14.6   30   W8  x  31  

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4.4. Column and Girder Layout with Beam Selections

Figures 16 and 17 show the girder layout with their selected beams for the roof and second floor respectively. Figure 18 shows the column layout with the selected columns.

 

Figure  16:  Girder  Layout  for  Roof  with  Labeled  Girders

 

Figure  17:  Girder  Layout  for  2nd  Floor  with  Labeled  Girders

 

Figure  18:Column  Layout  with  labeled  columns

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5. Appendix 5.1. Load Calculations

• Dead  Loads:  

♦ 𝑅𝑜𝑜𝑓  𝐷𝑒𝑎𝑑  𝐿𝑜𝑎𝑑 = 𝑅𝑜𝑜𝑓  𝑊𝑒𝑖𝑔ℎ𝑡 + 𝐶𝑒𝑖𝑙𝑖𝑛𝑔  𝑊𝑒𝑖𝑔ℎ𝑡  Ø Roof:  

§ 4in  thick  concrete  slab  (9.6  psf  per  inch  of  thickness)  § Steel  deck  =  5psf  § Steel  Joists  =  5  psf  § Insulation  =  1  psf  § Bituminous  smooth  surface  membrane  (1.5psf)  § 𝑤𝑒𝑖𝑔ℎ𝑡 = 9.6 !"#

!"4𝑖𝑛 + 5𝑝𝑠𝑓 + 5𝑝𝑠𝑓 + 1𝑝𝑠𝑓 + 1.5𝑝𝑠𝑓  

§ 𝑤𝑒𝑖𝑔ℎ𝑡 = 50.9𝑝𝑠𝑓  Ø Ceiling    

§ Suspended  steel  channel  system  =  2  psf  § Acoustic  tile  =  1  psf  § Ducting  =  4psf  § Lighting  =  1psf  § 𝑤𝑒𝑖𝑔ℎ𝑡 = 2𝑝𝑠𝑓 + 1𝑝𝑠𝑓 + 4𝑝𝑠𝑓 + 1𝑝𝑠𝑓  § 𝑤𝑒𝑖𝑔ℎ𝑡 = 8𝑝𝑠𝑓  

♦ 𝐷𝑒𝑎𝑑  𝐿𝑜𝑎𝑑 = 50.9𝑝𝑠𝑓 + 8𝑝𝑠𝑓  ♦ 𝐷𝑒𝑎𝑑  𝐿𝑜𝑎𝑑 = 58.9𝑝𝑠𝑓~60𝑝𝑠𝑓  

• 2nd  floor  Dead  Loads  ♦ 𝐷𝑒𝑎𝑑  𝐿𝑜𝑎𝑑 = 2𝑛𝑑  𝐹𝑙𝑜𝑜𝑟  𝑊𝑒𝑖𝑔ℎ𝑡 + 𝐶𝑒𝑖𝑙𝑖𝑛𝑔  𝑊𝑒𝑖𝑔ℎ𝑡  

Ø 2nd  floor:  § 4in  thick  concrete  slab  (9.6  psf  per  inch  of  thickness)  § Steel  deck  =  5psf  § Steel  Joists  =  5  psf  § Carpeting  and  padding  =  1  psf  § 𝑤𝑒𝑖𝑔ℎ𝑡 = 9.6 !"#

!"4𝑖𝑛 + 5𝑝𝑠𝑓 + 5𝑝𝑠𝑓 + 1𝑝𝑠𝑓  

§ 𝑤𝑒𝑖𝑔ℎ𝑡 = 49.4𝑝𝑠𝑓  Ø Ceiling    

§ Suspended  steel  channel  system  =  2  psf  § Acoustic  tile  =  1  psf  § Ducting  =  4psf  § Lighting  =  1psf  § 𝑤𝑒𝑖𝑔ℎ𝑡 = 2𝑝𝑠𝑓 + 1𝑝𝑠𝑓 + 4𝑝𝑠𝑓 + 1𝑝𝑠𝑓  § 𝑤𝑒𝑖𝑔ℎ𝑡 = 8𝑝𝑠𝑓  

♦ 𝐷𝑒𝑎𝑑  𝐿𝑜𝑎𝑑 = 49.4𝑝𝑠𝑓 + 8𝑝𝑠𝑓  ♦ 𝐷𝑒𝑎𝑑  𝐿𝑜𝑎𝑑 = 57.4𝑝𝑠𝑓~60𝑝𝑠𝑓  

• Roof  Live  Loads:  ♦ 𝐿! = 20𝑝𝑠𝑓  

Ø Industry  standard  • Live  Load  Second  Floor:  

♦ Light  storage  

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♦ 𝐿 = 125  𝑝𝑠𝑓  • Rain  Loads:  

♦ 𝑄 = 0.0104𝐴𝑖  Ø A=  Total  area  of  roof  =100!𝑥  40! = 4000  𝑓𝑡!  

§ Implement  2  drain  system  § Area  served  by  drain  =  2000𝑓𝑡!  

Ø 𝑖=  rainfall  intensity=  3  inches  per  hour  ♦ 𝑄 = 0.0104(2000)(3)  ♦ 𝑄 = 62.4  𝑔𝑝𝑚    ♦ Using  Table  2.5  in  notes,  𝑑! = 1𝑖𝑛,  and  assuming  4  inch  diameter  drain  ♦ 𝑅 = 5.2(𝑑! + 𝑑!)  

Ø 𝑑! = 1  𝑖𝑛,  from  table  2.5  in  Mike  11.    Ø 𝑑! = 2  𝑖𝑛,  given  in  example  Mike  11.  

♦ 𝑅 = 5.2 1+2  ♦ 𝑅 = 15.6  𝑝𝑠𝑓  

• Snow  Loads  ♦ 𝑆 = 𝑝! = 0.7𝐶!𝐶!𝐼!𝑝!  

Ø 𝐶! = 0.9  § Since  the  Engineering  design  center  is  a  Category  B,  Fully  Exposed  structure.  

(ASCE  7-­‐10,  26.7.3,  pg  251)  Ø 𝐶! = 1  Ø 𝐼! = 1.1  

§ Since  the  structure  is  a  risk  category  3  building  Ø 𝑝! = 0  

§ Since   the   elevation   of   the   building   is   3   ft   and   well   below   the   threshold  elevation  of  1500  ft  required  for  a  basic  ground  snow  load  in  Santa  Barbara.  

♦ 𝑆 = 𝑝! = 0.7 0.9 1 1.1 0  ♦ 𝑆 = 0𝑝𝑠𝑓  

• Wind  Loads:  ♦ Done   using   excel   table   below.   Highest   absolute   value   was   selected   (highlighted  

below)  

♦  • Seismic  Loads:  

♦ 𝑆 = 10𝑝𝑠𝑓  ♦ Given    

Constants h"18 h""30Risk"Category"IIIV=115"mph 115Kzt=1.0 1Kz"(18')=0.60 0.6Kz"(30')=0.70 0.7Cnet"Windward"Wall"+"Int"Pressure 0.43 8.734848 10.190656Cnet"Windward"Wall"K"Internal"Pressure 0.73 0.00112128 17.300416Cnet"Leeward"Wall"+"Int"Pressure K0.51 K12.086592Cnet"Leeward"Wall"K"Int"Pressure K0.21 K4.976832Cnet"Side"Walls"+"Internal"Pressure K0.66 K15.641472Cnet"Side"Walls"K"Internal"Pressure K0.35 K8.29472Flat"Roof"+"Internal"Pressure K1.09 K25.832128Flat"Roof"K"Internal"Pressure K0.79 K18.722368

2nd"Floor Roof

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5.2. LRFD Load Combination Table

Table  13:  LRFD  Worst  Case  Scenario  Excel  Sheet  

Roof (psf)D 60L 0Lr 20R 15.6W 25.8S 0f1 0.5f2 0.2H 0E Assumed 101.4D 841.2D+1.6(L+H)+.5Lr 821.2D+1.6(L+H)+.5S 721.2D+1.6(L+H)+.5R 79.81.2D+1.6Lr+1.6H+f1(L) 1041.2D+1.6S+1.6H+f1L 721.2D+1.6R+1.6H+f1L 97.01.2D+1.6Lr+1.6H+0.5W 116.91.2D+1.6S+1.6H+0.5W 84.91.2D+1.6R+1.6H+0.5W 109.91.2D+W+f1L+1.6H+.5*Lr 108.61.2D+W+f1L+1.6H+.5*S 97.81.2D+W+f1L+1.6H+.5*R 105.61.2D+1E+f1L++1.6H+f2S 820.9D+W+1.6H 95.3.9D+1.0E+1.6H 64

2nd floor Storage Area (psf)

D 60L 125E 10f1 0.51.4D 841.2D+1.6L 2721.2D+E+f1L 144.5

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6. References

American Institute of Steel Construction. Steel Construction Manual. 14th ed. N.p.: American Institute of Steel Construction, 2010. Print.

American Society of Civil Engineers. Minimum Design Loads for Buildings and Other

Structures. Reston, VA: American Society of Civil Engineers/Structural Engineering Institute, 2010. Print.

International Code Council. 2012 International Building Code. Country Club Hills, IL:

International Code Council, 2011. Print.