Optimizing “Big Box”

Construction

Lauren Hughes

Josh Hogan

Kevin Hanson

Joseph Garrott

Rose-Hulman Institute of Technology

Optimizing “Big Box” Construction

• Project Description

• Project Approach

• Research Results

• Future Work

Owners want to know….

Which wall to use?

Our Task

• Consider four different wall systems

• Perform a structural design of all four wall systems

• Complete cost estimate for all wall systems

Optimizing “Big Box” Construction

Create decision tool to determine most efficient wall system

Project Description

• Dr. Ed Alsamsam• Portland Cement Association

• Concrete as a building material

• Wants to make the decision easier for designers

Client

• Interviews with professionals • Investigation of wall systems• Design load calculations• Structural design • Construction planning &

scheduling• Cost estimate

Project Approach

ADVANTAGES• Elimination of formwork• Simple erection

DISADVANTAGES

• Labor intensive

• Locations of CMU plants

Concrete Masonry Shear Walls

ADVANTAGES• Versatility• Simple erection

DISADVANTAGES

• Forming labor & materials

• Curing time

Site-Cast Tilt-Up Panels

ADVANTAGES

• Quality control • Time savings • Elimination of formwork

DISADVANTAGES

• Transportation constraints

• Limited locations of plants

• Site constraints

Factory-Cast Tilt-Up Panels

ADVANTAGES

• Extra insulation

• Little or no maintenance

DISADVANTAGES• Height constraints • Limited shapes and sizes

Insulated Concrete Form Walls

Construction Planning & Scheduling

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

InsulatedConcrete Form

Walls

Site-Cast Tilt-UpPanels

Pre-Cast Tilt-UpPanels

Concrete MasonryUnits

Duration (Weeks)

Cost Estimate

• Microsoft Excel spreadsheet

• Based on Means Building Construction Cost Data

• Itemizes individual labor and material components of each wall system

• Input critical labor and material unit costs

• Output cost index per square foot of wall

Cost Estimate

Decision Tool Criteria

1. Is the building height greater than 20 feet tall?

2. Is there a precast plant within 100 miles?

3. Is there a masonry plant within 100 miles?

4. Are you willing to pay a premium for a faster completion?

5. Does the site have room for curing of site cast panels?

6. Does the site have crane access?

Decision Tool Example

An owner wants to build….

• 30 foot tall building• Nearest precast plant 50 miles • Nearest masonry plant 200 miles • Owner willing to pay for quicker completion• Sufficient flat space for formwork• Sufficient crane access

An owner wants to build….

• 30 foot tall building• Nearest precast plant 50 miles • Nearest masonry plant 200 miles • Owner willing to pay for quicker completion• Sufficient flat space for formwork• Sufficient crane access

Decision Tool Example

An owner wants to build….

• 30 foot tall building• Nearest precast plant 50 miles • Nearest masonry plant 200 miles • Owner willing to pay for quicker completion• Sufficient flat space for formwork• Sufficient crane access

Decision Tool Example

An owner wants to build….

• 30 foot tall building• Nearest precast plant 50 miles • Nearest masonry plant 200 miles • Owner willing to pay for quicker completion• Sufficient flat space for formwork• Sufficient crane access

Decision Tool Example

An owner wants to build….

• 30 foot tall building• Nearest precast plant 50 miles • Nearest masonry plant 200 miles • Owner willing to pay for quicker completion• Sufficient flat space for formwork• Sufficient crane access

Decision Tool Example

An owner wants to build….

• 30 foot tall building• Nearest precast plant 50 miles • Nearest masonry plant 200 miles • Owner willing to pay for quicker completion• Sufficient flat space for formwork• Sufficient crane access

Decision Tool Example

The most efficient wall system is

Factory-Cast Tilt-Up Panels!

Research Results

• Most significant components of total cost:• Material delivery• Regional variations in labor wages

• Cost of steel reinforcement varies little among the four wall systems

Future WorkContinuing Research• Greater detail in cost inputs• Fully automated tool• Interaction with professionals

Project Recommendations• Works well as a senior level design

project • Project is better as a team project • Scope and direction of the project

Summary

• Purpose – develop a decision tool to find most cost-efficient concrete wall system

• Results – flow chart to aid designers

Optimizing “Big Box” Construction