Structural Engineering

A STRUCTURAL ENGINEER ANALYZES AND DESIGNS THE GRAVITY SUPPORT AND LATERAL FORCE RESISTANCE OF BUILDINGS, BRIDGES, AND OTHER STRUCTURES.

What does a Structural Engineer do?

Structural Building Elements?

Foundations

Columns

Walls

Beams

Floors

Loads

Gravity Loads

Live Loads

Dead Loads

Lateral Loads

Wind Loads

Seismic Loads

Structural Engineering

Walls

Columns

Beams

Floor

Load Path - Gravity

Structural Engineering

Hanging Office

Load Path - Lateral

Structural Engineering

LATERAL LOAD

LATERAL RESISTANCEGROUND

What are the Rules for Structural Design?

City of Evanston

Website

Building Code Info

International Building

Code 2012

Evanston

Codes for Design

Structural Engineering

Design Codes

Structural Engineering

Codes that Govern Design

Structural Engineering

Image Credit: Thornton Tomasetti, Inc

Adaptive Re-use of Wrightwood Art Gallery

Image credit: TAAA SD Drawings

Wrightwood Art Gallery

Image credit: http://www.google.com

Tadao Ando

World renowned architect

from Japan

Known for his mastery of

concrete

Pritzker Award recipient

Wrightwood Art Gallery

Image credit: Thornton Tomasetti

http://www.google.com/maps

The Challenge

Why keep the existing

building?

Zoning restrictions

Ando’s desire for

“repurposed” aesthetic

But still have to

reconstruct interior

Wrightwood Art Gallery

Okay, but how?

Image credit: TAAA SD Drawings

A collapse would be bad

Structural System – Steel Framing

Image credit Thornton Tomasetti, Inc

It’s only “temporary” until it becomes permanent

Structural System – Steel Frame

Image credit Thornton Tomasetti, Inc

Inserting the steel frame

Structural System – Steel Frame

Image credit: Thornton Tomasetti, Inc

Back to the Future!

Structural System – One-way Concrete Joists

“Galloping” stirrup

Image credit: Thornton Tomasetti, Inc

A Blast From the Past

Structural System – Composite Design

Image credit: Thornton Tomasetti, Inc

A Blast From the Past

Structural System – Composite Design

Image credit Thornton Tomasetti, Inc

Don’t Brace Me In

Atrium Space

Image credit: Thornton Tomasetti, Inc

Supporting the New

Foundations – Micropiles

Image credit: Thornton Tomasetti, Inc

Reinforcing the Old

Foundations – Foundation Wall

Image credit: Thornton Tomasetti, Inc

Going Deeper: Jet Grouting at Elevator Pits

Foundations – Jet Grouting

The University of Chicago

Laboratory for Atmospheric and Space Research

LASR was in need of an update. In addition to a vertical expansion to add to the program space, a re-clad was

required to help meet thermal performance requirements to achieve LEED Silver certification, increase floor

space of the existing levels, maximize daylighting and modernize the appearance of the structure.

Transforming the structureBefore / After

In addition to expanding and recladding the structure, the owner and architect wished to reposition LASR to open it to the

new quadrangle to the south as well as greet its science and medical neighbors. The glazing and roof terrace connect the

LASR occupants with the new campus space.

Transforming the structureBefore / After

Steel afforded the contractor the flexibility to utilized staged construction on a cramped site. The steel columns were

placed atop the existing concrete columns. The capacity of the columns and foundations were analyzed for the

additional loads. We worked closely with our Geotechnical consultants to ensure the existing caissons were not

overstressed.

Reaching up: Vertical expansionSteel Advantages

The original designers had intended to add another story of concrete after the building was constructed in 1964. We were

able to add two stories of steel due to the lighter weight of steel and soil capacities obtained from geotechnical testing.

Reaching up: Vertical expansionSteel Advantages

The cantilevered seminar room was of extreme importance to the architect and owner’s vision. We worked with them to

support the structure while maintaining a picture window for connection to the quadrangle. To the right are hand sketches

we shared with the architect during design development

Defying Gravity…with SteelSteel’s Flexibility

The site was cramped and had its share of challenges,

all which made this such a rewarding endeavor.

Defying Gravity…with SteelSteel’s Flexibility

Fiber Reinforced Polymer (FRP) was used to reinforce beams that had demand that exceeded shear and/or moment

capacity. Extensive review with the City’s code reviewer to ensure proper fire-rating was conducted. We had planned to

utilize FRP to reinforce overstressed columns, but our final analysis determined this to be unnecessary.

Advance Technology for an Advance ProgramFiber Reinforced Polymer

Main historic features were carefully preserved and cleaned. New working

environment was integrated into this setting. Old postcard of The Clarence

Sidney Funk cloisters

The original building was more private and separated from the University of

Chicago due to the high wall.

What is now the ‘Graduate Commons’ the grand hall made a successful

transformation from a non-secular use to a study and gathering space.

Images demonstrate the relatively large amount of additional underground space that was

required to make this a success.

‘Found space’ - new underground classroom provides ample indirect lighting for a

more ergonomic teaching environment.

Available space below the courtyard was maximized. The New MEP structure walls are cast immediately

adjacent to the existing foundations.

Existing spread

footings elevation

Jacked piles used to support

existing foundations

The buildings are united along the old alleyway. New 2nd level corridor provides enhanced circulation and

greater programming space.

New main entrance provides unity to the building.

1. Post-tensioned cast-in-place beams support underground classroom roof. 3D modeling and

coordination made the design and construction of these easier.

2. Underground classroom ceiling with the architectural finishes, light is reflected into the study and

learning space below.

1.

2.

Completed ramp above underground classroom, the open landscaping, steps and ramp creates an

inviting atmosphere.

It is possible to see students below through the glass as you walk along the access ramp.

Every space has a use and the main historic features were preserved and integrated into student life.

The finished student lounge is warm and inviting.

New second story corridor, supported on steel columns provides enhanced circulation and allows for

larger tiered classroom within the existing building. Existing exterior wall is left exposed.

Amount of carbon dioxide equivalents emitted into the

atmosphere in the process of constructing a building

Embodied carbon

• Raw material extraction

• Refining

• Manufacturing

• Transportation

“Dust to Dust” Assessment

?Photo: Wikimedia Commons , IFCAR

Which car has a bigger lifecycle environmental impact?

The gas guzzling Jeep Wrangler

The green Toyota PriusPhoto: Wikimedia Commons , CGP Grey

Energy Use Over Time

Source: CSIRO

• Steel and concrete contribute

the largest amount of

embodied energy to a

project.

• Generally, the more highly

processed, the higher the

embodied energy.

Embodied Energy in Structural Materials

Environmental Product Declarations

Thornton Tomasetti San Francisco OfficePhoto :Benjamin Grimes

Life-Cycle Impact Reduction

Existing material reuse

• Flooring

• Bricks

• Doors

• Trim

• Framing lumber

• Mantels

• Granite

Material cost reduced by 8.38%

Community Housing of Maine, Main HallLEED Silver

Standards Are Changing

Costal Maine Botanical GardensPhoto courtesy of Anne Marie Rowlands French

Architecture 2030 Challenge for Products

Environmental Product Declarations (EPDs)

LEED Version 4

BIM for Analysis

What We Measure

Blast furnace slag

Embodied Energy

(MJ/kg)

Embodied Carbon

(kgCO2e/kg)

Fly ash

Recycled steel

Concrete strength

Rebar