Seismic Engineering

Qualified Engineer Needed?

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Various standards and codes require that an engineer’s services are to be used for certain scaffold designs and installations.  Is that really necessary?  After all, thousands of scaffolds are constructed daily without any input from engineers.  Furthermore, do these engineers need to be qualified engineers or will any engineer be acceptable?  And even furthermore, aren’t scaffolds only to be designed by a qualified person.  And even more furthermore, doesn’t the U.S. federal Occupational Safety & Health Administration, OSHA, have one regulation that requires a “registered professional engineer” and other regulation that requires a “qualified engineer?”  Is there a difference?  Can you be a qualified engineer without being a professional engineer and can you be a professional engineer without being qualified?  The answer is yes, yes, yes and yes.

While OSHA requires that all scaffolds shall be designed by a qualified person, that is, an individual who has the ability to solve or resolve the issues at hand, certain scaffolds shall be designed by a registered professional engineer, while in other cases a “qualified engineer” is allowed.  That sounds confusing but it shouldn’t be.  To become a qualified registered professional engineer, an individual must meet the requirements set forth by the engineering profession.  First, an individual must hold a degree from a recognized accredited school—typically a college or university.  After successfully passing an 8-hour exam on the fundamentals of engineering, the candidate must then work under the supervision of a registered professional engineer for at least 4 years.  At that time, the candidate is allowed to take another 8-hour exam to verify that he/she is qualified to become a professional engineer.  The next step is for the professional engineer to apply for registration in the state or province in which he or she chooses to work.  Some states require additional examination before granting registration.  For example, California requires that the candidate pass an exam on seismic engineering.  Upon payment of a fee, in some states a substantial fee, the candidate is granted registration.  The registration is typically a 2-year registration; renewal in most states requires continuing education.  It is important to note that in addition to registration as a professional engineer, many states require a license to offer engineering services and of course a permit to conduct business in the state of registration.  Registration is indicated by the use of the initials P.E. in the U.S. and P.Eng. in Canada behind the engineer’s name.  Registration can be easily verified on state/provincial websites.

Registration as a “registered professional engineer” does not mean that you are qualified to design scaffolds.  Registered Professional Engineers must comply with the regulations of the state in which they are registered and also should comply with the ethics promulgated by the profession.  One of the tenets, and rules, is that engineers only practice within their field of expertise.  This means that not all registered professional engineers are qualified to design scaffolds.  Unfortunately, there are engineers who think they have the expertise but don’t.  Abuse of the title is often seen in the courtroom where supposed “experts” proclaim knowledge of scaffolding and regulations.  It appears the courts have allowed great latitude in the term “expert witness” to the consternation of qualified engineers. 

State and provincial boards monitor engineers’ activities and punish those who violate the rules.  The punishment ranges from letters of admonition to fines to license cancellation to imprisonment.  Interestingly, one can have a legitimate degree in a field of engineering but cannot offer engineering services without being a Professional Engineer.  In other words, unless you are registered, you cannot offer to provide engineering services.  Licensure is a serious controlled business.

Unfortunately, the term “engineer” had been diluted over time, to the frustration of the professional engineering community.  While railroad locomotive engineers are known to be a different type of engineer than discussed here, the term engineer is used in many other fields of endeavor, where it can create confusion.  While it is expected that professional engineers meet certain criteria regarding physics, material strength, structural analysis and other science fields, a “sales engineer” clearly is not a professional engineer.  Safety engineers do not meet the normal criteria for a professional engineer.  Custodial engineers and software engineers are other examples. 

What does a qualified engineer provide that a qualified person cannot is a legitimate question that deserves an objective answer. Qualified engineers can determine the strength of materials, components and structures to determine if a design is adequate for its intended purpose.  Engineers can evaluate existing situations for structural adequacy and compliance with applicable standards, regulations and industry practices.  In the case of scaffolding, the engineer must know the applicable regulations, the equipment being used in the design, and the impact the design will have on adjacent structures.  Depending on the scope of work, the engineer may also be required to understand other aspects of the project, including contracts and scheduling.

  A qualified registered professional engineer can provide the assurance that a scaffold is correctly designed, will provide the expected functionality and, most importantly, will not collapse!  A qualified registered professional engineer can analyze situations and offer creative economical solutions.  There is no doubt that many scaffolds can be designed by a qualified person, that is an individual with the knowledge and expertise to solve or resolve the issues at hand.  However, there are instances when the situation requires the special advanced education and expertise of a qualified professional engineer.  If you don’t know what those circumstances are, your qualified registered professional engineer should be able to tell you.

What You Need to Know: Earthquake Resistant Buildings

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Earthquake resistant buildings save lives. They limit property damage and comply with the latest seismic building codes.

If you do business in high earthquake hazard areas, here’s what you need to know about seismic building codes.

1. Seismic Building Codes are Getting Tougher

In 2015, Los Angeles overhauled their seismic regulations. 15,000 buildings needed retrofitting to better withstand the effects of earthquakes.

For decades, safety advocates worked to pass ordinances strengthening two types of structures. First were the brittle concrete buildings on L.A.’s major boulevards. Second, the boxy wood-frame apartment buildings built on top of carports. Over 65 people died when these types of buildings collapsed during earthquakes in 1971 and 1994.

2. Designing Earthquake Resistant Buildings is a Regional Endeavor

Building codes are based on the base shear formula. This formula measures how much earthquake-generated shear force will try to push the house off the foundation base. The simple formula multiplies the expected ground acceleration by the building’s weight.

But there’s no set amount for anticipated ground acceleration. For example, Los Angeles anticipates a different base shear than the California Building Code does.  The International Existing Code’s ground acceleration is different still. Keeping this in mind, it’s always best to use a base shear that’s tailored to your geographic region.

3. It’s Not Just the Building, It’s The Ground Underneath

Earthquake resistant buildings are great. But let’s say a building’s foundation sits on soft soil. Despite the advanced engineering techniques used, it could still collapse in an earthquake.

But, if the soil beneath a structure is solid, engineers can improve how the entire building foundation system responds to seismic activity.

One example is base isolation. In this method, a building is floated above the foundation on bearings, springs or padded cylinders. A solid lead core is used for vertical strength with rubber and steel bands for horizontal flexibility. This allows the foundation to move without moving the structure above.

4. Seismic Engineering has a Bright Future

All around the world are examples of newer structures withstanding earthquakes. One example is the Transamerica Pyramid in San Francisco.

During the Loma Prieta quake, the building shook for more than a minute and the top floor swayed a foot side to side. A deep concrete and steel foundation and a buttressed exterior allowed the building to escape structural damage.

Sensor readings were taken from the building’s frame and processed by the U.S. Geological Survey. The results showed the building could withstand an even larger seismic event.

The future of seismic engineering doesn’t just look forward. Retrofitting older buildings is as important as new construction. One bright spot is engineers are effectively and economically adding base-isolation systems to existing structures.

After the 1989 Loma Prieta quake, engineers retrofitted the city halls of San Francisco, Oakland, and Los Angeles. These earthquake-resistant structures will be tested. When and how remains to be seen.

The Final Analysis

More jurisdictions are mandating seismic building code compliance. That’s where DHG comes in. Our experience with earthquake resistant design ensures your clients’ buildings will comply with the latest codes.

To see our seismic engineering services up close, contact us for a consultation.