siue project

7/27/2019 SIUE Project

http://slidepdf.com/reader/full/siue-project 1/12

Dalian Office Buildi

April 27, 2012

g



i

Table of Contents

Abstract ..................................................................................................................................................... ii

Scope and Background ............................................................................................................................. 1

Design Parameters .................................................................................................................................... 1

Applied loading......................................................................................................................................... 2

Structural Beam and Column Design........................................................................................................ 4

Lateral Bracing Design ............................................................................................................................. 6

Foundation Design .................................................................................................................................... 6

Engineering Fee Assessment .................................................................................................................... 7

Sustainability............................................................................................................................................. 7

Conclusion ................................................................................................................................................ 8

References................................................................................................................................................. 9

Figure 1 - Building RAM 3-D Model ............................................................................................................... 4

Figure 2 - Double Coped Beam ..................................................................................................................... 5

Table 1 - Summary of Uniform Area Loadings .............................................................................................. 2

Table 2 - Summary of Uniform Line Loadings ............................................................................................... 3

Table 3 - Building Deflection Criteria ............................................................................................................ 5Table 4 - Engineering Fee Assessment .......................................................................................................... 7



ii

Abstract

The purpose of this project was to use applicable design guides and software to construct a

model of a seven-story office building. The group learned how to use RAM Structural Systems,

which designed the structural components throughout the building including all of the steel

beams, columns, lateral bracing, and concrete foundation. Samples of these components were

spot checked by the group to insure the accuracy of the software. Due to the complexity of the

building, the group did not verify lateral bracing design with hand calculations, but had to set site

dependent criteria for seismic and wind loadings within RAM. Once all of the structural

components were designed by the software, the group learned how to create structural drawings

in Revit Structure. These drawings include a typical floor layout, column schedule, lateral

bracing elevations, and foundation plans and sections.



1

Scope and Background

The purpose of this project was to provide the structural design of a seven-story office

building with a three-story subgrade parking structure in Dalian, China. The design team

completed all work under the guidance of professors at campus and the structural engineering

division of a local firm. The office space will be constructed out of structural steel framing with

cast-in-place concrete decking. The parking structure and foundations will consist of reinforced

cast-in-place concrete.

For this project the design team was required to calculate all of the loads superimposed

on the building, create a model of the building in a structural software program, run the software

to design all of the members for the building, check the sizes of several typical members with

hand calculations, design the foundation, produce structural drawings for the completed designs,

calculate engineering fees associated with the project, and propose methods to include

sustainability in to the project. The parking structure is not within the scope of this project but

was realistically modeled and appropriately loaded so the foundations could be correctly

designed.

Design Parameters

The building is located in China; therefore the final design will be in accordance with the

Chinese Building Code. For the scope of this project, the Senior Design team was instructed not

to use the Chinese Building Code, but use applicable U.S. standards. ASCE 7-10 was utilized

for load calculations while AISC 14th

edition and ACI 318-11 codes were used for the steel and

concrete design portion of this project, respectively. The team used RAM Structural System



4/27/2012 CE – 493

2

v14.04.05 to model the building and then design the building’s steel and concrete members.

Once the steel and concrete designs were completed the structural drawings were produced using

Revit Structure 2010.

Applied loading

The building has several separate loading areas that were considered; typical office floor,

first floor corridor, corridors above first floor, heavy storage, light storage, mechanical rooms, as

well as flat and sloped roof loads. In addition to uniform floor and roof loading, several line

loads were considered including the building façade, stair openings, and the elevator and

plumbing chases. The applied live and dead loads are summarized in Tables 1 and 2 listed next.

Table

Dead Load

Total (psf)

Live Load

Total (psf)

Typ. Office Floor w/ 12" Raised Fl. 137 65Typ. Corridor Above First Floor 137 95

Typ. First Floor Corridor 137 100

Typ. Garage Concrete Floor 146 40

Typ. High Density Filing 147 250

Typ. Flat Roof With Mechanical

Equip. 173 27

Typ. Flat Roof Under Gable 115 125

Typ. Gable Roof Over Framed 22 20

Typ. Light Storage 147 125

Typ. Mechanical Room 285 150

Typ. Elevator Machine Room 47 150Table 1 - Summary of Uniform Area Loadings



4/27/2012 CE – 493

3

The applied wind loads were calculated by hand using the “All Heights Method” outlined

in ASCE7-10 (Chapter 27). Although the structural modeling software calculated and applied all

lateral loading on the structure, the wind load calculation was performed to become familiar with

the wind loading calculation process. The building is considered a risk category II building with

a wind exposure category of C and a basic wind speed of 115 miles per hour. The wind speed

and exposure categories were provided to the design team as part of the project specifications.

The team also considered seismic loading applied to the structure. The project

specifications indicated a soil site class C, seismic design category C, Ss of 0.56g, and S1 of

0.22g. This data was inputted into RAM Structural System and utilized to perform all seismic

load calculations.

Dead Load

Total (plf)

Live Load

Total (plf)

Stairs and Exits (perimeter line load) 167 100Exterior Façade, 1st Floor 1575 0

Ext. Façade, Above 1st Floor 1260 0

Elevator Shaft Walls 197 0

Plumbing Chase 197 0

Table 2 - Summary of Uniform Line Loadings



4/27/2012

Structural Beam and Colum

The structural model was

outline provided in the project s

design specifications for the stee

structure; composite beams and

non-composite members for the

system, floor slab consisting of

decking and 3000 psi normal we

concrete, ASTM grade A992 wi

flange beams, and hollow struct

steel members conforming to AS

grade A500.

The RAM model was set

design using the aforementioned

criteria. Review of the gravity b

and girder designs revealed that

applied moment on most membe

for most beam members was go

beams throughout the structure a

CE – 493

n Design

created in RAM utilizing a column gridline lay

ecifications. The building was modeled utilizi

l super

irders,

roof

etal

ight

e

ral

TM

up to

ams

oment capacity far exceeded the

rs. After further review it was determined that

erned by deflection, not flexure. The deflectio

re shown in Table 3.

Figure 1 - Buil

4

out and building

g the following

he steel sizing

n criteria for all

lding RAM 3-D Model



4/27/2012 CE – 493

5

In an effort to reduce cost, attempts were made to standardize beam sizes within typical

bays for constructability purposes. Also, beam sizing was modified to select sizes that would not

require double coping at beam to girder attachment points, further reducing fabrication cost. In

general, coping beams is the partial removal of the flange at the end of the beam to prevent

interference when attaching to the girder. Double coping beams

would require both the top and bottom flanges of a beam to be

partially removed to acquire the same result; a graphical

representation of double coping is shown in Figure 2.

The column design outputs from RAM were based on one of

eighteen loading scenarios of full load or pattern loading to

maximize the load effect on the column. If pattern loading governs the design, an accidental

moment will be applied to the column which could increase the size of the required column. All

columns have been designed as W14 sizes due to the relative square shape of this size member.

Hand calculations were performed for a typical beam and column to verify the design outputs

from RAM.

Steel Composite Interior Beams Steel Composite Spandrel Beams

Construction Dead < 2.50" Construction Dead < 2.50"

Post Composite Live Span/360 <

1.00"

Post Composite Live Span/360 <

0.25"

Post Composite Superimposed Span/300 Post Composite Superimposed Span/600 <0.375"

Net Total Span/240 Net Total Span/480

Table 3 - Building Deflection Criteria

Figure 2 - Double Coped Beam

http://www.dgcad.com



4/27/2012 CE – 493

6

Lateral Bracing Design

The lateral system for this structure is

composed of eight concentrically braced frames per

floor, four on each global axis. Moment frames were

considered for the design, but were eliminated as an

option in an effort to reduce cost of construction and

materials. The reduction in cost for using concentric

braced frames comes from their reduced ductility, which

results in fewer frames necessary to meet the lateral design requirements. Also, connections for

moment frames are more costly to fabricate. The frames have been located to maximize

symmetry and reduce induced torsional loading. A chevron style bracing, see Figure 2, has been

selected in an effect to reduce obstructions as compared to diamond or x-bracing, making it the

most viable and least obstructive option outside of moment frames.

Foundation Design

For the foundation design, the project specifications indicated that bedrock is located near

the base of the parking structure. The allowable bearing capacity for the bedrock is specified as

11 kips per square foot. Based on this data the foundation will be constructed of shallow spread

footings. Grade 60 rebar and 6000 psi normal weight concrete have been specified for the

foundation design. RAM produced designs for all continuous wall footings and pad footings in

the structure. Footings supporting the lateral frames are significantly larger than other footings

in the structure. Large uplift forces are governing the design of the lateral frame footings, not

allowable bearing pressure. By increasing the size and weight of the lateral frame foundations it

Figure 3 – Concentric Braced Frame (Chevron Style)

http://www.structuremag.org



4/27/2012 CE – 493

7

will eliminate the net uplift forces applied to the lateral frame footings. Two of the pad footings,

one interior and one exterior, were selected and hand calculations were produced to verify the

design outputs.

Engineering Fee Assessment

The team calculated the associated engineering fees based on data provided by the local

structural design firm. The fee was assed as 1% of the total cost of construction. See Table 4 for

calculation assumptions and assessed fee.

It is important to note that calculated fee is for the completed structural engineering design,

including the parking structure.

Sustainability

The design team is proposing several methods to incorporate sustainability into the

Dalian Office Building project. The most significant is the use of structural steel that has been

produced using recycled steel scrap. According to the American Institute of Steel Construction

Office

Space

Parking

Garage

Price/ft2 $200 $100

Total Area (ft 2 ) 221,250 95,000

Total Cost $53,750,000Engineering

Fee $537,500

Table 4 - Engineering Fee Assessment



4/27/2012 CE – 493

8

(AISC) all structural steel produced in the United States contains 93.3% recycled steel scrap.

The design team also is proposing the use of supplementary cementitious materials (SCMs) in

the concrete mix design. According to the Portland Cement Association, fly ash or slag cement

may be used to replace up to 25% or 50% of the cementitious material respectively. The use of

SCMs significantly reduces greenhouse gas emissions, up to 45%, increasing the sustainability of

the structure (PCA 2012). The design team did not specify using SCMs throughout the structural

design process; but SCMs should be used in the concrete mix design, as long as the nominal

compressive strength matches the design requirements. The design specifications already

include precast concrete wall panels, which is a sustainable product, for the building façade.

Conclusion

The design team has successfully completed all tasks in the scope of work. Setbacks that

occurred during the design process were effectively handled in a timely manner which resulted in

on time completion of the Dalian Office Building project. From this project the design team

learned how to use RAM Structural System to model buildings, and then run different analyses

to design all of the structural components throughout the structure. By using the design data

from RAM, the design team then learned how to use Revit Structure to create construction

drawings.



4/27/2012 CE – 493

9

References

American Concrete Institute (ACI). (2011). Building Code Requirements for Structural

Concrete (ACI-318-11). American Concrete Institute. United States of America.

American Institute of Steel Construction (AISC). (2011). Steel Construction Manual, 14th

Ed.,

AISC, United States of America.

(AISC). “There’s always a solution in steel.” Designing for sustainability,

<http://www.aisc.org/content.aspx?id=17560> (Mar. 13, 2012).

American Society of Civil Engineers (ASCE). (2010). ASCE 7-10, Minimum Design Loads for

Buildings and Other Structures. ASCE, Reston, VA

PCA. “Concrete thinking for a sustainable world.” Recycled content,

<http://www.concretethinker.com/solutions/recycled-content.aspx> (Mar. 13, 2012).

siue project

Documents