<< Back to Construction Incident/Investigation Reports (Abridged)

Investigation of the December 19, 2008 Collapse of Atlanta Botanical Garden Canopy Walkway During Construction in Atlanta, GA

Attachment A Lab Report


May 29, 2009

Mr. Benjamin Ross
Assistant Regional Administrator for Enforcement Programs
U.S. Department of Labor – OSHA
Atlanta Regional Office
61 Forsyth Street SW, Room 6T50
Phone: 404-562-2300
Atlanta, Georgia 30303 email: Ross.Benjamin@dol.gov
   
Subject: Report for Material Testing Services
W10 and W8 Steel shoring beams
Atlanta Botanical Gardens Incident
Atlanta, Georgia
TEC Services Project No. TEC 09-0429.01
Dear Ross:  


Testing, Engineering, and Consulting Services Inc. (TEC Services Inc.) is pleased to submit this report of our materials testing performed for the subject project. The purpose of our work was to perform chemical and physical materials testing of select shoring beams to determine yield and ultimate strength of the steel for compliance with ASTM A36 and /or ASTM A992 specifications. This report briefly presents background information and the results of our materials testing. Our services were performed in accordance with our OSHA contract.

BACKGROUND INFORMATION

TEC Services was contacted by Michael Shea of OSHA regarding the subject project. We understand that OSHA requests materials testing of selected W8 and W10 steel beams that were used as shoring beams for the subject project. We understand that these beams were removed from the project site after a collapse during a concrete pour.

TEC Services was original contacted by Hardin representatives to perform selected testing. However, it was decided by the project team for TEC Services to perform the materials testing directly for OSHA. In an e-mail on April 17, 2009, Mr. Shea and Mr. Mohammad Ayub of OSHA requested a specific scope of materials testing be performed on 6 selected beams. The purpose of this testing is to determine if the steel materials satisfy the ASTM A36 and/or ASTM A992 specification.

FIELD OBSERVATIONS

On May 5, 2009 Mr. Philip Bender of TEC Services met with Mr. Marvin Sasser (Hardin Construction) and Mr. Americo Pagan (OSHA) at the Powder Springs warehouse to perform field measurements and obtain approximate 3 foot long samples from the six selected W8 and W10 beams. Field measurements of the selected beams were performed near the ends and middle of each member. Beam depth and flange width were obtained by steel rule and web and flange thickness measurements were obtained by ultrasonic thickness gauge. Field measurements were compared to AISC published values and ASTM A6-04. Some flange thickness dimensions were as much as 10% less than AISC published values. Our filed dimensions are included in Table 1 attached.

Six approximate 3 foot long beam samples were removed and returned to Lawrenceville, Georgia laboratory for further testing. Samples for testing were removed from beams labeled 6SX02, 6SX03, 6SX09, 7SX08, 7SX09, and 8SX03. A gas powered cut off saw was used to remove the samples from one end of each beam. Mr. Bender brought beam samples to the TEC Services Laboratory for testing.

LABORATORY MATERIALS TESTING

Select material properties were tested and compared to ASTM specifications to determine the grade of steel used in the six selected W8 and W10 shoring beams. TEC Services performed tensile testing of the specimens to determine yield strength, ultimate strength and elongation of the material in substantial compliance with ASTM A370-05. IMR Test Labs performed chemical testing in accordance with ASTM A36-08. Per request, TEC Services also reviewed the results of the chemical testing and compared them to the chemical requirements for ASTM A992-06. The IMR Test Labs cover letter with chemical analysis test results is included as an attachment to this report.

The results of the chemical testing indicate the shoring beams tested (6SX02, 6SX03, 6SX09, 7SX08, 7SX09, and 8SX03) meet the requirements of ASTM A36 and ASTM A992 steel. The results of the physical tensile testing indicate the material meets the requirements of ASTM A36 steel (minimum yield strength of 36 ksi, ultimate strength 58 ksi to 80 ksi, and minimum elongation of 21%). Two of the six beams tested (6SX03 and 8SX03) do not meet the physical requirements of ASTM A992 steel (yield 50 ksi to 65 ksi, minimum ultimate testing strength of 65 ksi, and minimum elongation of 21%.) A summary of our physical testing results is included in Table 2 attached.

CONCLUSIONS

Based on our physical and materials testing, the provided beams meet the requirements of ASTM A36 steel. Four of the six beams tested also meet the requirements of ASTM A992 steel (6SX02-W10x19, 6SX09-W10x12, 7SX08-W8x10, and 7SX09-W10x19). Two of the six beams tested do not meet the requirements of ASTM A992 (6SX03-W10x12 and , 8SX03-W8x10). Some section flange thickness measurements were less than AISC published dimensions.

We appreciated the opportunity to provide our professional services to you and the management team on this important project. Should questions arise concerning this proposal or if we may be of further service please contact us at 770-995-8000.

Sincerely,


TESTING, ENGINEERING AND CONSULTING SERVICES, INC.


Signature on file

Philip J. Bender
Project Engineer
  Signature on file

Kurt W. Heinrichs, P.E.
Principal Engineer
GA Registration No. 18741

Attachments

Table 1. Beam Measurements with Nominal Designation
Table 2. Summary of Physical Test Results
IMR Cover Letter with Chemical Analysis Results
Instron Stress vs. Strain Curves


IMR Logo





IMR Logo
  IMR Test Labs - Charleston
4500 Leeds Avenue, Suite 306, Deck 70
Charleston, SC 29405

Phone 843.740.2901 Fax 843.745.1165
Email imr@imrcharleston.com
PO Number
2009110

TEST REPORT

IMR Report Number 90470
 
Date Received
May 7, 2009

Description
I-Beam Samples
TEC Project # 09-0429

Sample ID
6SX02 A
6SX03 A
6SX09 A
7SX08 A
7SX09 A
8SX03 A

Material
Carbon Structural Steel

Specifications
ASTM A36-08
SUMMARY
Six samples measuring approximately 1.5" by 2.5" - 3" and labeled by the client were received for chemical composition analysis. Figure 1 shows the samples as received.

The samples meet the chemical composition requirements of ASTM A36-08 for all structural steel shapes.

Results are provided on the follow page(s).

  Reviewed by Reviewed by
  Signature on file

Michael Carroll
Metallurgist
Signature on file

Wil Barwick
Lead Analytical Chemist


All procedures were performed in accordance with the IMR Quality Manual, current revision, and related procedures. The information contained in this test report represents only the material tested and may not be reproduced, except in full, without the written approval of IMR Test Labs. IMR Test Labs - Charleston maintains a quality system in compliance with the ISO/IEC 17025 and is accredited by the American Association for Laboratory Accreditation (A2LA), certificates #740.01 and #740.02. IMR Test Lab's liability to the customer or any third party is limited to the amount charged for services provided. All samples will be retained for a minimum of 1 month and may be destroyed thereafter unless otherwise specified by the customer. The recording of false, fictitious, or fraudulent statements or entries on this document may be punished as a felony under federal statutes.

TEC Services Page 1 of 2 IMR # 90470
     
IMR Test Labs • 4500 Leeds Avenue, Suite 306 • Charleston, SC 29405

RESULTS              
Element Beam Samples (wt. %) Requirements for
all 1Shapes
(wt.%)
6SX02A 6SX03A 6SX09A 7SX08A 7SX09A 8SX03A
Carbon 0.08 0.14 0.10 0.16 0.08 0.21 0.26 max
Manganese 0.84 0.68 0.83 0.93 0.83 0.71 Not Specified
Phosporus 0.01 0.02 0.01 0.01 0.01 0.02 0.04 max
Sulfur 0.02 0.03 0.04 0.02 0.02 0.02 0.05 max
Silicon 0.19 0.23 0.25 0.18 0.16 0.06 0.04 max
Chromium 0.02 0.13 0.05 0.13 0.03 0.05 Not Specified
Copper 0.10 0.21 0.27 0.31 0.16 0.02
Molybdenum 0.01 0.02 0.03 0.03 0.01 < 0.01
Nickel 0.04 0.10 0.14 0.10 0.05 0.03
               
1Unless copper steel is specified or the flange thickness is over 3 inches
Method(s): ASTM E415-08

Figure 1: Samples as received
Figure 1: Samples as received

TEC Services                                                                 Page 2 of 2                                                                IMR # 90470



TEC Logo
TEC SERVICES
Testing Engineering Consulting
TESTING, ENGINEERING & CONSULTING SERVICES, INC.
JOB NAME:   OSHA  
JOB NUMBER:   09-0429.1  
BY: Philip J. Bender DATE: 5/20/2009
CHECKED BY: Kurt W. Heinrichs DATE: 5/20/2009


Table 1. Beam Measurements with AISC Nominal Designation

  Field Measurements  
Beam Label   Flange   AISC Reported
Nominal Designation
Depth, d Width, bf Thickness, tf Thickness, tw
(in) (in) (in)* (in)*
6SX02 10 1/4 4 0.357 0.262 W10x19
10 1/4 4 0.352 0.260
10 1/4 4 0.349 0.262
AISC** 10/1/4 4 0.395 0.250
6SX03 9 15/16 4 0.200 0.202 W10x12
9 15/16 4 0.201 0.199
9 15/16 4 0.194 0.204
AISC** 9 7/8 4 0.210 0.190
6SX09 9 15/16 3 15/16 0.225 0.193 W10x12
10 3 15/16 0.226 0.192
10 3 15/16 0.227 0.190
AISC** 9 7/8 4 0.210 0.190
7SX08 7 15/16 4 0.213 0.174 W8x10
7 15/16 4 0.203 0.174
7 15/16 4 0.207 0.176
AISC ** 7 7/8 4 0.205 0.170
7SX09 10 3/8 4 1/16 0.386 0.274 W10x19
10 3/8 4 1/8 0.367 0.267
10 3/8 4 1/16 0.367 0.271
AISC** 10 1/4 4 0.395 0.250  
8SX03 8 3 15/16 0.204 0.175 W8x10
7 15/16 3 15/16 0.203 0.177
8 3 15/16 0.209 0.177
AISC** 7 7/8 4 0.205 0.170

* - Measured with Ultrasonic Thickness Gauge
** - AISC 2005 Edition Published Dimensions

    - Indicates dimension below AISC published dimension



TEC Logo
TEC SERVICES
Testing Engineering Consulting
TESTING, ENGINEERING & CONSULTING SERVICES, INC.
JOB NAME:   OSHA  
JOB NUMBER:   09-0429.1  
BY: Philip J. Bender DATE: 5/20/2009
CHECKED BY: Kurt W. Heinrichs DATE: 5/20/2009


Table 2. Summary of Physical Tests

Sample ID Yield Strength
(0.2%, offset),
Fy

Ultimate Strength,
Fu
Modulus, E Elongation
(ksi) (ksi) (ksi) (%)
6SX02-W1 59 69 29,059 36%
6SX02-W2 58 69 29,050 36%
6SX02-F1 57 68 28,873 36%
6SX02-F2 56 67 28,981 36%
         
6SX03-W1 48 68 29,062 34%
6SX03-F1 46 66 29,377 29%
6SX02-F2 47 66 29,224 27%
         
6SX09-W1 53 68 29,329 34%
6SX09-F1 51 67 29,340 33%
6SX09-F2 52 66 29,031 31%
         
7SX08-W1 57 76 29,098 30%
7SX08-F1 55 76 29,131 28%
7SX08-F2 55 76 29,458 30%
         
7SX09-W1 62 71 29,125 35%
7SX09-F1 56 67 29,078 36%
7SX09-F2 60 70 29,051 33%
         
8SX03-W1 53 71 29,080 31%
8SX03-F1 47 68 28,470 27%
ASTM A36 36 (min) 58 -80 N/A 21% (min)
ASTM A992 50 -65 65 (min) N/A 21% (min)

    - Does not meet ASTM A992 Specification Tensile Requirements


Chart 1. Specimen Identification: 6SX02-F1, 6SX02-W1, 6SX02-W2, 6SX02-F1 - For problems with accessibility in using figures and illustrations, please contact the OSHA Directorate of Construction at (202) 693-2020.
Chart 1. Specimen Identification: 6SX02-F1, 6SX02-W1, 6SX02-W2, 6SX02-F1

Chart 2. Specimen Identification: 6SX03-F1, 6SX03-W1, 6SX02-F2 - For problems with accessibility in using figures and illustrations, please contact the OSHA Directorate of Construction at (202) 693-2020.
Chart 2. Specimen Identification: 6SX03-F1, 6SX03-W1, 6SX02-F2

Chart 3. Specimen Identification: 7SX08-F1, 7SX08-W1, 7SX08-F2 - For problems with accessibility in using figures and illustrations, please contact the OSHA Directorate of Construction at (202) 693-2020.
Chart 3. Specimen Identification: 7SX08-F1, 7SX08-W1, 7SX08-F2

Chart 4. Specimen Identification: 6SX09-F1, 6SX09-W1, 6SX09-F2 - For problems with accessibility in using figures and illustrations, please contact the OSHA Directorate of Construction at (202) 693-2020.
Chart 4. Specimen Identification: 6SX09-F1, 6SX09-W1, 6SX09-F2

Chart 5. Specimen Identification: 7SX09-F1, 7SX09-W1, 7SX09-F2 - For problems with accessibility in using figures and illustrations, please contact the OSHA Directorate of Construction at (202) 693-2020.
Chart 5. Specimen Identification: 7SX09-F1, 7SX09-W1, 7SX09-F2

Chart 6. Specimen Identification: 8SX03-F1, 8SX03-W1 - For problems with accessibility in using figures and illustrations, please contact the OSHA Directorate of Construction at (202) 693-2020.
Chart 6. Specimen Identification: 8SX03-F1, 8SX03-W1


For problems with accessibility in using figures and illustrations, please contact the
OSHA Directorate of Construction at (202) 693-2020.