28 minute read
Code Updates
ASCE 7-10 Wind Provisions and Effects on Wood Design and Construction
By Philip Line, P.E. and William L. Coulbourne, P.E., M. ASCE
The major change for wind design in ASCE 7-10, Minimum Design Loads for Buildings and Other Structures, is often broadly described as the introduction of new wind speed maps (referred to as ultimate wind speed maps in the 2012 International Building Code (IBC)). Several coordinated changes include: • revised load factors for wind in allowable stress design (ASD), and load and resistance factor design (LRFD) load combinations; • removal of the Occupancy Factor for wind due to new wind speed maps that vary by Risk Category (analogous to Occupancy Category); • reinstating applicability of Exposure D in hurricane prone regions; • revised wind speed triggers for definition of hurricane prone region and wind-borne debris region; and, • revised pressure values for minimum design loads.
Comparison of Design Velocity Pressure
The net effect of changes to mapped wind speeds and wind load factors on the calculated design velocity pressure can be significant in some locations, as shown in Table 1. Locations outside of the hurricane prone region, excluding special wind regions, can be generally represented by a ratio of approximately 1.0, as shown for Dallas, TX. An expected outcome, due to the uniform hazard basis of the new maps, is Figure 1: Application of minimum wind loads. that design pressures for Exposure C locations in the hurricane prone low-rise buildings designed in accordance region (Boston, Virginia Beach, and Miami) with the envelop procedure for low-rise are smaller under ASCE 7-10. Assuming buildings. For comparison, the minimum Exposure D, which is applicable in hur- design pressure of 10 psf, applicable for ricane prone regions per ASCE 7-10, an both walls and roofs under ASCE 7-05, approximate 10 percent increase in design when factored for LRFD is equal to 16 psf pressure is observed for Boston, MA and an (i.e. 10 psf x 1.6 = 16 psf). approximate 16 percent decrease in design pressure is observed for Virginia Beach, VA. Wind Speed Triggers Minimum Design Wind Loads
Minimum wind load provisions of ASCE 7-10 for design of main wind force resisting systems (MWFRS), under the directional procedure and envelop procedure, have also been revised to specify a minimum 16 psf wall pressure and a minimum roof pressure of 8 psf projected onto a vertical plane (Figure 1). And, it is now less likely to be the controlling minimum design wind load, particularly for some building configurations in lower wind speed regions and for Changes to mapped wind speeds are also coordinated with revision of several windspeed “trigger” values, such as the definition of hurricane prone regions (Figure 2). The revised wind speed trigger in ASCE 7-10 for hurricane prone regions (i.e. 115 mph) represents an algebraic conversion of the wind speed trigger in ASCE 7-05. Revised wind speed triggers for wind-borne debris regions and glazed opening protection have also changed, and do not follow the same conversion and exclusive linkage to wind speed maps for Risk Category II.
Table 1: Comparison of design velocity pressures using ASCE 7-10 and ASCE 7-05 (33-foot mean roof height).
ASCE 7-10 ASCE 7-05 Ratio
[A] [B] [C] Design Exp C Exp D Design Exp C Risk Wind Speed Velocity Velocity Wind Speed Velocity Location Category (MPH) Pressure (psf) Pressure (psf) (MPH) Pressure (psf) [A]/[C] [B]/[C] Boston, MA II 128 35.7 42.1 105 38.4 0.93 1.10 Va Beach, VA II 122 32.4 38.2 114 45.2 0.72 0.84 Miami, FL II 170 62.9 74.2 146 74.2 0.85 1.00 Dallas, TX II 115 28.8 - 90 28.2 1.02 Boston, MA III, IV 140 42.6 50.3 105 44.1 0.97 1.14 Va Beach, VA III, IV 132 37.9 44.7 114 52.0 0.73 0.86 Miami, FL III, IV 181 71.3 84.1 146 85.3 0.84 0.99 Dallas, TX III, IV 120 31.3 - 90 32.4 0.97 -
Figure 2: Illustration of hurricane prone regions (FEMA P-804).
Coordination with Codes and Standards
IBC adopts ASCE 7-10 provisions for wind design by reference, and incorporates ASCE 7-10 wind speed maps. A conversion of mapped wind speed to an ASD basis (i.e. Vasd per 2012 IBC is calculated as Vasd = Vult x 0.61/2) is added to the IBC to coordinate with previously established IBC wind speed triggers. For wood construction, the conversion is necessary for use of tables covering attachment of wood structural panels for wind, wind applicability limit for conventional light-frame construction, and wind uplift connector requirements in Section 2308. Within the 2012 International Residential Code (IRC), new maps illustrate ASD-based wind speeds. The IRC format of the wind speed map eliminates the need for conversion of the mapped value as is done in the IBC; however, the contour lines do not directly align with those in ASCE 7-10 maps incorporated in the IBC. The 2012 Wood Frame Construction Manual (WFCM) for One- and Two-Family Dwellings includes ASCE 7-10 Risk Category II wind speed maps, tabulated requirements for wind speeds ranging from 110 mph to 195 mph for both Exposures B and C, and a conversion table to adjust tabular values for Exposure D. The removal of the occupancy factor adjustment to wind loads in ASCE 7-10 will generally limit ease of applicability of WFCM load tables to other occupancy categories. Prior WFCM load tables were based on occupancy Category II, and were easily adjusted by the occupancy factor.
Summary
Model building codes and standards that rely on the new wind design approach in ASCE 7-10 include the 2012 IRC, the 2012 IBC, and the 2012 WFCM. Each of these documents addresses implementation of ASCE 7-10 in a different manner. This will likely create confusion for the users of these documents, as they reconcile new wind speed basis of ASCE 7-10 maps and different formats of the maps appearing in the 2012 IRC and 2012 IBC. For wood construction in accordance with the WFCM, the Risk Category II wind speed map is incorporated into the standard directly as it appears in ASCE 7-10 and tabulated requirements will be associated with ASCE 7-10 mapped wind speeds.▪
Philip Line, P.E. is the Director, Structural Engineering, American Wood Council. He may be reached at pline@awc.org. William Coulbourne, P.E., M. ASCE is the Director, Wind and Flood Hazard Mitigation, Applied Technology Council. He may be reached at bcoulbourne@atcouncil.org.
This article is based on a more comprehensive paper outlining additional details on changes to wind load provisions in ASCE 7-10. The longer, more comprehensive version has been posted online at STRUCTURE’s website, www.STRUCTUREmag.org.
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NCSEA News
Hotel Monteleone, New Orleans, Louisiana February 10-11, 2012
Soft Soil – Water and Wind
Friday/Saturday lectures, along with a Friday afternoon tour of the Inner Harbor Navigation Canal (IHNC) and Lake Borgne Surge Barrier.
Friday, February 10
8.0 Professional Development Hours
8:00 a.m. – 8:10 a.m. – Introduction of Topic 8:10 a.m. – 9:10 a.m. – Overview: Inner Harbor Navigation Canal (IHNC) and the Lake Borgne Surge Barrier The centerpiece of the New Orleans Hurricane and Storm Damage Risk Reduction System (HSDRRS), the Inner Harbor Navigation Canal (IHNC)–Lake Borgne Surge Barrier, is designed to reduce risk for some of southeast Louisiana’s most vulnerable areas (New Orleans East, metro New Orleans, Gentilly, Ninth Ward and St. Bernard Parish) from storm surge generated in Lake Borgne and the Gulf of Mexico during a 100-year event. Nearly two miles long and 26 feet high, it is the largest design-build civil works project in the history of the Corps. Angela DeSoto Duncan, P.E., is the Director for Civil Works, TetraTech INCA Engineers. She recently joined INCA after a 24-yr career with the Corps of Engineers. She was the Corps Design Lead for the IHNC-Lake Borgne Barrier and was responsible for Corps design oversight of the project. 9:10 a.m. – 10:10 a.m. – Geotechnical Engineering and Test Pile Program, Lake Borgne Hurricane Surge Barrier The Lake Borgne Hurricane Surge Barrier comprised the installation of a 1.8-mile long barrier wall, three navigational structures, and two floodwall transitions to existing hurricane protection. This presentation describes the subsurface investigation, pile load tests, and geotechnical decisions that were necessary to support the aggressive schedule for the installation of the barrier wall piles. The barrier wall is comprised of vertical 66-in. diameter concrete cylindrical piles and 36-in. diameter steel pipe driven on batters. William Gwyn, P.E., the Geotechnical Engineer of Record, is the President of Eustis Engineering, a geotechnical engineering and materials testing firm that specializes in the soft deltaic and alluvial soils that typify southeastern Louisiana. 10:30 a.m. – 11:15 a.m. – Structural Design of Gates The IHNC Lake Borgne Surge Barrier is constructed near the confluence of the Gulf Intracoastal Waterway (GIWW) and the Mississippi River Gulf Outlet (MRGO), a natural funnel indentified as an area of critical vulnerability in the Hurricane and Storm Damage Risk Reduction System (HSDRRS). The design consists of two 150-foot-wide flood control gates at GIWW (a buoyant sector gate and a concrete barge swing gate), a 56-foot-wide vertical lift gate with vehicular bridge at Bayou Bienvenue, and complete floodwall closure of the MRGO. The gates are closed in advance of a hurricane, providing surge protection with a watertight barrier to elevation EI 26.0. The IHNC sector gate is a fully buoyant steel gate designed to be closed in advance of hurricane landfall and can be operated with up to 10 feet of differential head. Dale Miller, P.E., S.E., the Project Engineer of Record, is currently serving as one of the PIANC U.S. Commissioners and managing the design of the IHNC Lake Borgne Surge Barrier Project in New Orleans, including two miles of innovative floodwall and three major navigation gates. 11:15 a.m. – 12:00 p.m. – IHNC–Overcoming Construction Challenges In April of 2008 the U.S. Army Corps of Engineers awarded their largest ever design-build civil works contract to Shaw Engineering and Infrastructure Inc. (Shaw E&I, Inc.) for the engineering, procurement and construction of the IHNC HSDRRS. This presentation will address the challenges and lessons-learned for the construction of this non-traditional one-of-a-kind civil works project. Charles M. Hess, Vice President of Operations for Shaw E&I, Inc., and Shaw’s FEMA Account manager, was responsible for all aspects of Shaw’s FEMA Individual Assistance – Technical Assistance Indefinite Delivery/Indefinite Quantity (ID/IQ) contract. 12:00 p.m – 1:00 p.m. – LUNCH 1:00 p.m. – 1:45 p.m. – Moderated Discussions and Video Highlights Enroute to the IHNC 1:45 p.m. – 4:30 p.m. – Tour–Inner Harbor Navigation Canal (IHNC) and the Lake Borgne Surge Barrier 6:30 p.m. – 7:30 p.m. – RECEPTION
Register at www.ncsea.com.
Cost: $350 for one day, or $595 for both days. Price includes breakfast, lunch, breaks, and Friday reception. Accommodations: Reserve your room at the Hotel Monteleone by January 17, 2012, and pay the reduced rate of $165 per night.
8:00 a.m. – 9:15 a.m. – ASCE 7-10 Wind Loading and Design This session includes coverage of revised wind speed maps and a building classification system based on risk of a natural hazard to the building or contents instead of occupancy, as used in the past. It will focus on the analytical (directional) method for determining wind pressures, including wind pressure determination for both the Main Wind Force Resisting System (MWFRS) and Components and Cladding (C&C). William L.Coulbourne, P.E., holds Certifications in Structural Engineering and Building Inspection Engineering and is a national expert in wind and flood mitigation. He has been involved in FEMA Mitigation Assessment Teams for over 15 years, including every major hurricane and flood disaster since 1995. 9:15 a.m. – 10:30 a.m. – Design Aspects of Fluid-Containing Walls, Soil-Retaining Walls and Flood Walls on Soft Soils This presentation will review some of the design and construction aspects to be accounted for in layout, jointing and construction of three types of reinforced concrete walls for fluid-containing structures, soil-retaining structures and hydrodynamic flood walls founded on soft soils. Design examples of each type of wall will be reviewed, illustrating the design differences and foundation considerations required by structural engineers, along with an application to a replacement flood wall system for the HSDRRS. Mike Sheridan, P.E., SECB, is the Lead Structural Engineer for the Memphis District of the U.S. Army Corps of Engineers and has 26 years of private and public structural engineering experience. 10:45 a.m. – 12:00 a.m. – Building Design for Coastal Flooding Improved foundation performance is one significant contribution to reducing losses from severe coastal events and helping communities recover faster. This session will present information on how to identify all coastal hazards, including the effect of scour and erosion on the flood loads and foundation design. An example of a coastal foundation design will be included. William L. Coulbourne, see 8:00 a.m. session. 12:00 p.m. – 1:00 p.m. – LUNCH and presentation by Dennis Boehme, Hayward Baker 1:00 p.m. – 2:00 p.m. – Foundations in Soft and Challenging Soils When designing foundations in soft soils, there are three options: Use the soft soil directly, improve the soil, or use deep foundations. This talk will focus on ground improvement and deep foundations, describing the different techniques available and giving guidance for their use. Mike Wysockey, P.E., Ph.D., is the President of Thatcher Engineering, a specialty subcontractor working in design-build earth retention, pile driving, drilled foundations, and marine construction. His publications range from shore erosion, to the effect of local soil conditions on earthquake motions, to the capacity of deep foundations. 2:00 p .m. – 3:00 p.m. – Design of Piles and Piers for Lateral Loads Design of deep foundations for lateral loads will be discussed in two parts, battered piles and plumb piles, with the majority of the presentation focusing on vertical piles, outlining design procedures, and case histories. Mike Wysockey, see 1:00 p.m. session. 3:15 p.m. – 4:15 p.m. Hurricane and Tornado Shelter Design This session will provide technical information important to consider when designing shelters for use in either tornados or high wind events such as hurricanes. The wind load provisions of ASCE 7-10 Minimum Design Loads for Buildings and Other Structures, the ICC-500 Storm Shelter Standard, and FEMA 361, Design and Construction Guidance for Community Safe Rooms, form the basis for this presentation. William L Coulbourne, see 8:00 a.m. session.
Prepare for exam day success with this SE exam review course designed by the National Council of Structural Engineers Associations (NCSEA), Kaplan Engineering Education, and leading structural engineers from across the profession.
January 21-22: Vertical Forces Review February 25-26: Lateral Forces Review
Visit www.ncsea.com and follow the “Hot Topics” link for the NCSEA/Kaplan SE Exam Review Course, to register and for more information on the course and the instructors.
Upcoming NCSEA Webinars
January 10, 2012: Rehabilitation of Timber Structures – Paul Gilham January 24, 2012: Reorganization of the ACI 318 Building Code – Randall W. Poston, Ph.D., P.E., S.E. These courses will award 1.5 hours of continuing education. The times will be 10:00 am Pacific, 11:00 am Mountain, 12:00 pm Central, and 1:00 pm Eastern. Approved in All 50 States.
NCSEA News
The Newsletter of the Structural Engineering Institute of ASCE Structural Columns
Thursday, March 29, 2012
Track Blast
8:00 AM – 9:30 AM
New and Innovative Materials for Blast Protection Seismic Design of Midrise Cold-Formed Steel Framing Systems Chicago’s Leadership in Tall Buildings Floor Vibration Serviceability Can Alternative Delivery Method Help the Engineering Community?
Seismic Buildings 1 Buildings 2 Business 1
10:00 AM – 11:30 AM
Predicting Blast Loads Associated with Complex Threat Environments Seismic Design and Analysis: General Topics Tribute to Clyde Baker’s Impact on Chicago High Rise Building Foundations Integrating Environmental and Seismic Performance Metrics Trial Designs and Building Code Issues
12:00 PM – 1:45 PM Opening Plenary Luncheon and Awards Program
2:00 PM – 3:30 PM
Blast Effects on Infrastructure Innovative Seismic Solutions I Healthcare and Research Facilities Achieving Design Build success with Early Involvement of Specialty Contractors and a Collaborative, Model Driven Process 2011 Masonry Code & Specification Update
4:00 PM – 5:30 PM
Collapse Resistance of Steel Frame Structures: Connection Behavior, Slab Effects, and Robustness Assessment Innovative Seismic Solutions II Advances in Full-Scale Monitoring of Tall Structures Sustainability and Steel Evaluation and Analysis of Existing Masonry Structures
5:30 PM – 6:30 PM Young Professionals Mixer 6:30 PM – 8:00 PM SEI and PCI Welcome Reception in Exhibit Hall (Sponsored By PCI)
Friday March 30, 2012
7:00 AM – 8:15 AM CASE Breakfast
Track Blast
8:30 AM – 10:00 AM
The New ASCE/ SEI Standard for Blast Resistant Design Achieving Economy and Seismic Safety in LowDuctility Steel Buildings The History of Chicago’s Highrise Structures 2011 Tornado Season: Lessons in Building Design for Structural Engineers Profitability Killers and How to Avoid Them
10:30 AM – 12:00 PM
Blast Resistant Structures in the Petrochemical Industry Seismic Base Isolation and Damping Chicago Sports Stadiums SEI Reconnaisase Report on the Christchurch Earthquake Key Financial Indicators to Look for When Running a Structural Firm
Seismic Buildings 1 Buildings 2 CASE
12:00 PM – 1:30 PM Buffet Lunch in Exhibit Hall
1:30 PM – 3:00 PM
Multi-Hazard Robustness Assessment Building Structural Systems From Hazard to Design – A Case Study of the Benefit on Nonlinear Response History Analysis in Practice Wind Loads on Super-Tall Towers Preliminary Study of the Damage Caused by the 2011 Tohoku Earthquake Making the Transition from Project Manager to Principal – Panel Discussion
3:30 PM – 5:00 PM
Design Concepts for Progressive Collapse Mitigation What the Future Holds: ASCE 41-13 – Seismic Evaluation and Upgrade of Existing Buildings Human Perception of Motion in Wind-excited Tall Buildings Performance of Structures in the Canterbury New Zealand Earthquakes
6:00 PM – 9:00 PM Chicago! Mid America Club Reception (Sponsored by Alfred Benesch and Co. and Thornton Tomasetti, Inc.)
Saturday March 31, 2012
Succeeding at Ownership & Leadership Transition During Uncertain Times
Track Blast Seismic Buildings 1 Buildings 2 Sustainability
8:00 AM – 9:30 AM
Blast Resistant Curtainwall Design Considerations for Timber Buildings
10:00 AM – 11:30 AM
Historic Structures: Balancing Blast Protection & Aesthetics Reducing Seismic Risk for Soft-Story Woodframe Buildings Design and Construction Planning of Iconic Tall Buildings with Current Technologies and Global Perspective – Part 2 Innovative Solutions to Challenging Stability Design Problems Sustainability and the Structural Engineer: The First World ChallengeTEJH Synopsis
Design and Construction Planning of Iconic Tall Buildings with Current Technologies and Global Perspective Steel Connection Design Sustainable Structural Engineering-Gaining Greater Benefits to Communities in Developing Nations
12:00 PM – 1:45 PM Closing Plenary Luncheon and Business Meeting 2:00 PM – 6:00 PM Post Conference Seminars
Non-Building
Structures 20th A&C Bridge Practice
Wind Loads on Solar Collectors Systems and Rooftops Recent Innovations and Application of Passive Seismic Control I ABC’s of Rapid Construction
Advances in Analysis and Design of Wind Energy Structures Recent Innovations and Application of Passive Seismic Control II
Opening Plenary Luncheon and Awards Program Evaluation and Retrofit New Directions in of Petrochemical Damage Detection Strucutres and Pipelines Using Structural Health Monitoring Emerging Trends in Rail Bridges
Transit Rail and Movable Bridges Bridge Research and
Implementation PCI Special Topics
Seismic Effects I Diaphragm Seismic Design Methodologies – Part 1 How Digital Databases are Changing the Ways in which Engineers Do Research and Write Codes
Seismic Effects II Diaphragm Seismic Design Methodologies – Part 2 Finite Element Analysis of Nuclear Structures
Seismic Effects III Concrete Structures Behavior in Recent Seismic Events Student Structural Design Competition
Tunnel and Underground Structures: Second Avenue Subway Project, New York Selected Issues in Analysis and Computation Movable Bridges Experimental Investigation of the Seismic Performance of Horizontally Curved Bridges
Young Professionals Mixer SEI and PCI Welcome Reception in Exhibit Hall (Sponsored By PCI) Concrete Blast Resistant/ Disproportionate Collapse Design Life-Cycle Performance of Structural Systems under Multiple Hazards
CASE Breakfast
Non-Building
Structures 20th A&C Bridge Practice
Seismic Response of Nonstructural Systems in the Tests at E-Defense Optimal Design Using Advanced Computational Methods Aesthetics and Special Criteria for Pedestrian Bridge Designs
Design, Analysis and Testing of Nonstructural Components Benchmark Cases of Optimum Structural Design Pedestrian Bridge Vibration
Buffet Lunch in Exhibit Hall Bridge Research and
Implementation Business 2 Special Topics
Finite Element Analysis Techniques for Fatigue and Fracture Evaluation and Design IDOT Ongoing and Recently Completed Research, Development and Implementation Efforts The Typical Claim Against a Structural Engineer – Panel Discussion
The Case of the Sagging Floors Topics in Structural Engineering Education and Research
International Buildings
Seismic Testing, Analysis, Qualification, and Performance-based Design for Raised-access Floors and Equipment NB230 – Miscellaneous Topics on Nonbuilding Structures/Nonstructural Advances in Hybrid Simulation
Calibration and Validation of Concrete Models Midwest DOT Bridges Design of Concrete Bridges with Innovative Materials Demarcating the Profession: Where Should We Draw the Line? Design of Timber Buildings: General Considerations
Structural Collapse Due to Snow: 2010-11 Winter
Chicago! Mid America Club Reception (Sponsored by Alfred Benesch and Co. and Thornton Tomasetti, Inc.)
Non-Building
Structures 20th A&C Bridge Practice
Bridge Research and
Implementation Business 2 Special Topics
Design of Unique and Unusual NonBuiliding Structures
Evaluation and Design of New and Existing Buildings Against Disproportionate Collapse Unique Structures Recent Advancements in Collapse Assessment of Structures Under Earthquakes International Bridges Implementation of Structural Health Monitoring in Management and Inspection of Bridges Cabled Stayed Bridges Construction and Special Topics
Closing Plenary Luncheon and Business Meeting Post Conference Seminars Lessons Learned from the Recession and Where Do We Go from Here Retrofit of Concrete
Creative, Collaborative, and Communicative: Perspectives on Developing a Future Generation of Engineering Leaders Forensic Engineering
To view the interactive Technical Program, including all presenters and abstracts, on the SEI Website, visit www.structurescongress.org
CASE in Point
The ACEC Council of American Structural Engineers (CASE) is currently seeking contributions to help make the structural engineering scholarship program a success. The CASE scholarship, administered by the ACEC College of Fellows, is awarded to a student seeking a Bachelor’s degree, at minimum, in an ABET-accredited engineering program. We have all witnessed the stiff competition from other disciplines and professions eager to obtain the best and brightest young talent from a dwindling pool of engineering graduates. One way to enhance the ability of students in pursuing their dreams to become professional engineers is to offer incentives in educational support. In addition, the CASE scholarship offers an excellent opportunity for your firm to recommend eligible candidates for our scholarship. If your firm already has a scholarship program, remember that potential candidates can also apply for the CASE Scholarship or any other ACEC scholarship currently available. Your monetary support is vital in helping CASE and ACEC increase scholarships to those students who are the future of our industry. All donations toward the program may be eligible for tax deduction and you don’t have to be an ACEC member to donate! Contact Heather Talbert at htalbert@acec.org to donate.
CASE Announces the Release of Two NEW Products!
CASE 9-2: Quality Assurance Plan
Elements Essential for Quality Client Service High-quality client service – from project initiation through construction completion – is critical to achieving project success and maintaining key client relationships. Elements essential for quality service include: • Client and project ownership by the individuals responsible for the project. • Continual staff education, including both leadership and technical skill development. • Firm-wide standard of care. • Quality control process with a complete communication loop. • Written Quality Assurance Plan. As part of the Ten Foundations of Risk Management, CASE Tool 9-2: Quality Assurance Plan provides guidance to the structural engineering professional for developing a comprehensive, detailed Quality Assurance Plan suitable for their firm. A well-developed and implemented Quality Assurance Plan ensures consistent high-quality service on all projects, and includes: 1) Quality Control Review 2) Firm-wide Standards 3) Construction Quality Assurance The quality control review may consist of three elements: Design (Jury) Review, Engineering Review and Construction Document Review. Comprehensive firm-wide standards (consisting of design/analysis standards, documentation standards and construction administration standards) enable staff to gain historical firm-wide benefits while providing resources to ensure the design and documentation are clear, concise, accurate and consistent. Construction quality assurance is an important element of the quality assurance plan since it is the final step in the process. Developed by the CASE Toolkit Committee, this tool is available at www.booksforengineers.com.
CASE Document 7-2011
Commentary on AIA Document A295–2008 “General Conditions of the Contract for Integrated Project Delivery” The American Institute of Architects (AIA) has developed a family of documents intended for use when the Integrated Project Delivery method is used. These documents are entirely new, not updates of existing documents. The Integrated Project Delivery approach is a collaborative process involving all participants through all phases of the Project. The AIA documents assume that the primary parties in Integrated Project Delivery are the Owner, Architect, and Contractor, and the Agreements are written in that manner. Another document prepared by the AIA is titled Integrated Project Delivery: A Guide, which provides the principles and techniques of Integrated Project Delivery from the AIA perspective, and appears to be the basis for the provisions of AIA Document 295-2008. The SER should read and become familiar with AIA Integrated Project Delivery: A Guide before entering into an Agreement for an IPD project. CASE Document 7-2011 provides assistance to the Structural Engineer of Record (SER) when entering into an agreement with an Architect when the project delivery approach is Integrated Project Delivery. Developed by the CASE Contract Committee, this commentary is available at www.booksforengineers.com.
The Council of American Structural Engineers (CASE) is a national association of structural engineering firms. CASE provides a forum for action to improve the business of structural engineering through implementation of best practices, reduced professional liability exposure and increased profitability. Our mission is to improve the practice of structural engineering by providing business practice resources, improving quality, and enhancing management practices to reduce the frequency and severity of claims. Our vision is to be the leading provider of risk management and business practice education, and information for use in the structural engineering practice. Your membership gets you free access to contracts covering various situations, as well as access to guidance on AIA documents, free national guidelines for the Structural Engineer of Record designed to help corporate and municipal clients understand the scope of services structural engineers do and do not provide, free access to tools which are designed to keep you up to date on how much risk your firm is taking on and how to reduce that risk, biannual CASE convocations dedicated to Best Practice structural engineering, bi-monthly Business Practice and Risk Management Newsletter, AND free downloads of all CASE documents 24/7. For more information go to www.acec.org/case or contact Heather Talbert at htalbert@acec.org. You must be an ACEC member to join CASE. You can follow ACEC Coalitions on Twitter – @ACECCoalitions.
CASE Business Practice Corner
If you would like more information on the items below, please contact Ed Bajer, ebajer@acec.org.
Responsibility after Being Value Engineered
If a design is value-engineered, is the original design invalidated? The engineer that value-engineered the project still has an obligation to perform to the prevailing standard of care and, generally, would be required to seal any modifications but probably only the modifications. The original engineer is not released from liability for errors and omissions in the original design by the revision, but would not have responsibility for the revisions unless they reviewed and approved them. With properly worded language, the VE engineer can limit his/her liability to only their revisions.
Asked to Certify Something Beyond Control
Many public entities are issuing contracts that require the retained engineer to provide “certifications” that go well beyond the engineer’s scope of work and beyond the engineer’s experience or knowledge. Some states have statutory language that says the use of “certify” or “certification” constitutes a professional opinion and does not amount to a warranty or guarantee, express or implied. Some state Boards have language that the engineer should decline to sign or seal any document that relates to matters beyond their technical competence or their scope of services.
Authority to Stop Work
Some contract documents allow the Engineer to stop work that may become defective, even though the same documents may expressly state safety procedures are the domain of the contractor. Some firms disclaim the right to stop work under any circumstances. However, if the engineer “assumes” control of site safety through their actions, they may lose any immunity granted to them and severely impact their insurance coverage. There should be no question of what to do in the case of imminent danger. The consequences for failure to take action prior to an accident are far greater than when accused of entering into the domain of the contractor’s safety responsibilities.
Contract Language: Comply With All Codes, Standards and Regulations
This is common language in many contracts. The problem is with “all”. Thousands of laws and regulations are on the books. They change frequently and are open to interpretation. In some cases, they conflict with one another. As a professional you are already required to comply with codes and laws, and if you don’t it’s negligence per se. If you can, delete this clause from your contract and delineate your obligation in your scope of services. If you can’t delete the clause, try to delete the word “all” or put in a finite date when this responsibility ends.
