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 to Know About Falsework

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With any large construction project, there are multiple stages where the structure isn’t ready to support itself.

That’s where falsework comes in. Similar to a parent’s job with their child, falsework’s job is to provide support until the structure can be supported on its own.

What else is important to know about falsework’s role in construction? Keep reading to learn more.

1. It is Different Than Formwork!

First off, falsework is not synonymous with formwork! While both of these structures play similar roles in construction, they have key differences to be aware of.

First, let’s just define what it is we are talking about. Falsework is defined as any construction used to support vertical loads for another structure until it becomes self-supporting. It is commonly used when supporting girders or arch bridges.

If falsework’s job is to support, then formwork’s job is to mold. Formwork holds the concrete in place until it hardens to the desired shape.

The concepts are similar, but it is critical to use the terminology correctly to avoid confusion.

2. Types of Falsework

There are various types of falsework components in the market, some that are marketed as systems by different manufacturers. Some systems use aluminum frames and leg assembly. Other systems will utilize props made of steel, while others will simply incorporate wood.

Typically, you will encounter a combination of systems and random components as part of a complete falsework assembly on a job-site. One such example would be a shoring tower for bridge girders. These can contain a mix of steel, aluminum, and wood components for one single tower.

3. Centring

This is not a typo – we do indeed mean centring and not “centering”. This term is commonly used in architectural terms to describe the support of arches during construction.

During construction, arches and domes are unstable until the keystone is inserted at the top of the arch. Centring works to support and hold up the arch until it is completed and able to support itself.

4. It Can Be Used with New and Old Structures

The way we have referred to falsework’s role so far makes it seem like it is only used with new projects or the construction of new structures. While it is most commonly used in these circumstances, it is possible to use it with existing structures as well.

Falsework can be used as a temporary support for structures that have been damaged, that were left incomplete, or for overloaded structures that are past their service life.

Older buildings might need this kind of temporary support for several reasons. It could have been damaged after years of use or even from natural disasters and need to be rebuilt. Or it could just be breaking down and need to be repaired, like old historical buildings for example. Another common use is for brick facade retention during the remodeling of a buildings interior.

Bottom Line

Stress and pressure aren’t just things you feel during a big construction project; the building or bridge is feeling pressure well! Falsework provides support and takes on the loads and stresses so that your structure will be supported even when it can’t support itself.

We mentioned that the design and implementation of this type of support can be difficult, and many factors must be considered. It is always recommended to get a qualified engineer involved when supporting these large structures, and DHG’s team of falsework engineers is happy to help. Contact us today to learn more about our falsework design services.

4 Tips for Safe Demolition

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Are you aware of the regulations that govern demolition of buildings, bridges, and other structures? Did you know that regardless of the type of structure being demolished, the same set of OSHA standards apply?

Before you start tearing down that next structure, it’s important to have your safety protocol in place. You’ll want to be sure you comply with the appropriate OSHA standards, and that you’re taking the right steps to keep everyone in the area safe.

These four important measures will help get you on the right path to safe demolition. Read on to find out more.

The Basics of Demolition

1. Training Your Employees – Who is Responsible?

When it comes to demolition, it’s important to make sure that only experienced and properly trained employees perform this type of work. Contrary to industry belief, demolition is far from an unskilled task. Removing any structural member can destabilize the entire structure, and increase the chance of unplanned collapse. Only employees who have been trained thoroughly under the supervision of a competent person should ever be allowed to perform this type of work.

It is the employer’s responsibility to provide training for the specific work environments that will be encountered during the demolition process. OSHA clearly defines this duty in 1926.21(b)(2).

2. Provide Proper PPE – More Than the Simple Stuff

One would hope this would be obvious, but based on our anecdotal observations, one would be wrong! It is critical that all personnel not only have the correct equipment on hand, but they must be using it properly. This includes the basics – hardhats, safety vests, proper eyewear, hearing protection, gloves, steel-toed boots, etc.

Depending on the type of demolition, specialty project specific equipment may also be required. This could include fall protection, respirators, hazmat suits, and other items.

The Competent Person is responsible for making an assessment of the job site to determine what specific hazards may be encountered, and what equipment will be necessary.

3. Brace! Stabilize! Brace! Stabilize!

Question – would you remove the legs from a table while eating dinner from it, expecting it not to fall over (this is not a trick question)? Of course not! Similarly, would you think it is ok to remove structural supports from a bridge or building without first figuring out how to stabilize it? Let’s all pray the answer to that is “no” as well!

OSHA 1926.850(a) requires that prior to demolishing any structure, an engineering survey by a Competent Person must be performed. If the structure is complex, a Qualified Person (i.e. professional engineer) may be required to provide a sequenced demolition plan with engineered bracing and shoring layouts.

Demolition of large structures is tricky business. When in doubt, get an engineer involved.

4. Clean Up Properly

After demolition is complete, your work isn’t over. It’s also important to make sure the cleanup process is done safely.

Jagged concrete and exposed rebar are just two of many hazards encountered after the jackhammering has stopped. When possible, it is always recommended to utilize loaders and skid steers for debris removal. If hand removal is required, the competent person needs to be extremely vigilant to ensure employees handle the debris piles safely.

Final Thoughts

Thousands of demolition projects are completed safely every year. Following these tips (which are by no means exhaustive) along with the guidance provided in OSHA Subpart T will help ensure your next demolition project is done safely as well.

Need help with an upcoming demolition project?

Get in touch with our demolition engineers today and learn how we can help.

The Many Benefits of Value Engineering

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Let’s face it, most companies could stand to operate in a stronger, more effective manner. Be it time wasted in meetings or too many resources used, these mistakes can be costly.

In the construction world, value engineering is a great way to combat that waste. Created during World War II by General Electric, this process is all about helping businesses become more efficient.

And if you’re a contractor, there’s one universal truth: your process could be more efficient. And what does efficiency lead to? More money.

Read on to learn why it’s time to invest in value engineering services.

Value Engineering Advantages

Bidding & Value Engineering

While faster timelines and teamwork are great (we will dive into that later on), let’s first focus on the overall goal here: profits. And by investing in value engineering services, you’ll ensure that your company is adding more to the bottom line than ever before.

A revelation to many companies is that value engineering is not just achieved during the project, but it can be even more effective before bid time.  It’s shocking to see how many companies wade into a bid simply winging it: “Sure, that beam is probably big enough for that wall”, or even better “Yeah, we should be able to get away with only one crane for that critical lift.”

Wouldn’t it be nice to know what it will actually take to build your project before you bid it?  Two outcomes will be achieved in this exercise.  First, no cost surprises during construction – raise your hand if you ever “won” a bid you wish you would have lost! Second, increased bid winning percentages – bid confidently knowing you can build the project faster and cheaper than your competition, no more “padding” necessary.

“But if I lose the bid, how am I supposed to account for the engineering costs?”  This is the line in the sand that separates the sophisticated contractors from everyone else, and where we need to think about the big picture.

The smart contractor will look at the cost of value engineering in the bidding phase as an expense, not as a cost of goods sold (COGS).  Trying not to go into an accounting lesson here, but an expense is just like any other general or administrative cost such as paper or pens for the office.  COGS are actual project costs like materials and field labor. Why is this distinction important?

Smart contractors expense the value engineering because they know that they will not win every bid.  They set an annual budget for it and spread this expense into their overhead. They do this knowing that they will get a far greater return than this amount over the course of an entire year. A recent client example looked something like this:

  • – $ 25,000 engineering investment
  • + $100,000 annual project cost savings
  • = $ 75,000 annual net profit (300% ROI)

Does an investment that yields 300% seem like something you want? I’ll assume so given the fact the most recent interest rate on a “high yield” savings account is 1.15%.

Conversely, other contractors instead look only at the immediate result, and view the up-front engineering cost as COGS. “I spent $2,000 on pre-bid engineering and I lost the project, now I just have to eat it. I’m never doing that again!”

Think of the absurdity of that statement.  Imagine yourself walking into Caesars Palace, winning a bet, and then Caesars abruptly shuts down the casino. Crazy, right?  A Casino will never do this because they know over the long run, they will win that money back – and then some. Losing even 100 bets means nothing because they will win 110 bets back!

Similarly, companies in the ENR Top 50 don’t stop spending money on pre-project engineering because they lose some bids here and there. Instead they forge ahead knowing that over the long run, they will have a great return on their investment!   

The choice here is what type of contractor do you want to be?  Great contractors, and great companies for that matter, think about the long run and focus on the big picture.  Big picture focus = big profits. 

Overall Scheduling Outlook

Worried about how adding engineering services could impact your schedule?  Don’t be.  One of the key performance metrics that is reduced by value engineering is overall project duration.

If the engineering takes two weeks to complete but shaves four weeks off your schedule – this is a win for you and your project.

The trick is to not focus on the immediate schedule impact – think in the long-term when evaluating your options. Just as mentioned before, you must focus on the big picture.

Your Clients Get a Better Result

Construction is ultimately about creating what the client has envisioned. Focused value engineering will by definition provide your client with the same outcome for lesser cost. Depending on contractual obligations, the contractor may pass on or keep the savings.

From a customer service perspective, owners always appreciate the contractor who is considerate and mindful of their specific needs.  Building owners will be much happier with the result if you provide them with a value engineered structure that minimizes maintenance costs.  Modest value changes such as adding some additional cheap roof anchors can save them tens of thousands of dollars over the life of the building in window washing costs.

Simply presenting your client with value options will ensure them that you are constantly focused on their best interests. 

Your Team Will Come Together

Value engineering can be a team building experience. Bringing the project group together to solve a complex problem will galvanize relationships. You will also find out who your superstars are as the best members of your team will rise when presented the challenge.

By the end of your value engineering experience, your team will be stronger and morale will be higher.

Start Saving Money Today

Ready to take the next step from simply being good, to instead being great? We would love the opportunity to help take you to that next level.

Get in touch today to learn how you can leverage all the value engineering services DH Glabe & Associates has to offer.

OSHA Update: Walking Working Surface Regulations

By | Blog, Facade Access, Fall Protection, OSHA Standards & Regulations | No Comments

Earlier this year, OSHA made headlines for the way it would revise the regulations regarding fall protection for general industry.

Did you know about the change?

As explained by the department itself, the modification accounts for modernization of technology along with updates to old regulations.

It’s important that building owners and managers understand the new developments. If you don’t, you could be facing fines from the government – or worse, accidents at your property with increased legal liability. 

There are several subtle changes in the regulations that have large implications.  Specifically, the changes in fall protection for facade access and building maintenance could potentially be costly for building owners.

Here’s what you need to know.

Standards for Window Washing & Exterior Maintenance

You’re probably aware of the complicated protocol that already exists around suspended scaffolding systems.

Now, a few new rules have been tossed into the mix for General Industry. OSHA has basically adopted various ANSI, ASME, and IWCA standards that were loosely followed in the past.  These are now law with clearly defined minimum requirements. 

The most important example is the minimum load any rope descent (i.e. boatswain or bosun’s chair) anchorage must now support. Prior to this update, a minimum of two to one safety factor was allowed (typically resulting in an anchor that could support around 1800 pounds). Now, ALL anchorages must be able to hold 5,000 pounds minimum.

Height standards are also changing for rope descent systems. No rope descent system can be anchored 300 feet above the base of a building barring some sort of extraordinary circumstance. Owners of buildings above this threshold will now have to accommodate the switch to powered platforms for window washing.

The ANSI/IWCA I-14 standard was widely considered the industry standard regarding anchorage testing and inspection. OSHA has now adopted the intent of this standard into the 1910.27 regulation. Building owners are now required to have their roof anchorages load tested upon installation, inspected annually, and load tested again every ten years.

The key takeaway from these changes is that OSHA is shifting much of the safety burden onto building owners and away from contractors.  Building owners are now REQUIRED to provide and have written certification that their anchorages meet the new standards.  Gone are the days where contractors could provide temporary anchorages to aid in window washing and exterior maintenance. 

Deadlines for Implementation

The new regulations for rope descent can be costly as mentioned, but OSHA is not allowing much time for building owners to get up to speed. There are no “grandfather” type exceptions in the regulation, just a set deadline of November 20, 2017 to comply.

What does it mean if your building is not ready by then?

To put it simply, you will not be allowed to legally wash your windows or undergo exterior maintenance work until it is. There are options such as boom lifts for lucky building owners that have properties accessible from the ground, but any type of rope descent access that requires overhead suspension is not allowed.

Penalties for Accidents

There are no new fines that have been introduced as part of this new OSHA regulation overhaul. Keep in mind though that OSHA already approximately doubled fines towards the end of 2015.   

Fines however, could be the least of one’s worries. As most building owners already know, potential legal damages in the event of a serious accident would far exceed any fines OSHA could levy. Throw a non-compliant building into the case, and the liability skyrockets. 

A Good Thing?

Those who will face the immediate brunt of these costs will certainly disagree that this is good change in the short run.  However, the new regulations have many benefits:

  1. Standardization of many loosely followed standards into one clear-cut law;
  2. Increased protection for workers. With permanent exterior maintenance systems now mandated, the potential for falls decreases;
  3. No more guessing – workers now know for certain whether the anchorages their lives depend on are safe for use;
  4. Long term savings in risk premiums as accidents are mitigated.

Regardless if this OSHA update benefits you or not, it is important that you understand it like the back of your hand.

Update Your Facade Access System Now

Dirty windows can make for cranky tenants. The sun’s harmful UV rays continuously pound building exteriors. If you are unable to wash windows or provide exterior maintenance against weathering, your building is in trouble.

The team at DH Glabe & Associates has the expertise to get your building compliant in the most cost-effective manner possible.

Feel free to reach out to someone on our team today to learn how we can help you.

FEA: The Next Best Stress Analysis

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The future of stress analysis has actually been around for over 60 years!

Finite Element Analysis (FEA), also known as Finite Element Method (FEM) is being used in the most modern applications, but the methodology has been effective for over half of a century.

What can it do for your company? Keep reading to get a brief overview.

What Is Finite Element Analysis (FEA)?

In a nutshell, the finite element analysis is a numerical method for solving problems in engineering and mathematical physics. It measures how a design will respond to weight, pressure and stress. Will it bend, break, or hold?

It’s best used when analyzing problems involving complicated geometry, loads, and material properties when analytical solutions can’t be obtained.

An analytical solution will do a stress analysis for trusses or beams, with mass concentrated on the center of gravity. Whereas FEA helps with more complex design geography.

It can help you understand:

  • The strength, heat transfer capability and fluid flow of complex objects
  • The performance and behavior of a complex design
  • The strengths and weaknesses of the design

The History of Finite Element Analysis

It can be traced as far back as A. Hrennikoff and R. Courant in the early 1940s, who used the methods of elasticity and structural analysis for aeronautical engineering.

Then in the late 50s and early 60s, China’s K. Feng used it for analysis of dam construction.

Today, the fundamentals are still one of the most reliable methods of stress analysis, trusted by people across the world.

According to Andres Gameros, “This analytical methodology has been used since the 1960s. In the years since its first use, Finite Element Analysis has grown and developed into a standard of design engineering worldwide.”

FEA has ushered in several commercial software packages which are used around the world, including Solidworks and LUSAS amongst many.

The Real World Uses for This Form of Stress Analysis

Today, this type of stress analysis is being used in:

  • Aircraft like the Boeing 787-9 Dreamliner
  • Complex bridge design
  • Some of the world’s biggest brands including General Motors (GM), Faraday Future, and Siemens
  • The oil industry
  • Aerospace engineering
  • High-end construction
  • Biomedical research and the textiles

As Autodesk’s Vikram Vedantham explained, “Structural FEA has the capability to influence engineering at multiple levels – from mainstream solutions that provide trends and insights to guide product development, to high-end solutions that aim to match real-world data.”

He added, “Picking features and capabilities is determined by the time of use, the persona involved, the level of depth, the geometry, the nature of the design, its use case and the size of the firm.”

So how does one pick a firm to take care of their FEA or any other type of stress analysis? Choose the firm with proven expertise, as well as a combined 5,500 projects, 32 years of combined experience and 54 combined professional licenses.

To learn more about how we can help you, please feel free to contact us.

Hanging Out

By | Blog, Resources, Scaffolding | No Comments

The suspension rope supporting a temporary platform is the single most important element of a suspended scaffold. You may not agree with this—too bad for you. What if the rope breaks? The platform can only go down and if you are at a considerable height, the result will be mostly unpleasant. Understanding this suggests that we should probably be sensitive to the condition of the rope to which we trust our lives.

What is a rope? A typical definition describes a rope as a cord that consists of twisted strands of material, such as hemp or wire. Of course, that begs the question of what cords and strands are. For that matter what is hemp? Can you smoke it? Perhaps not. How about this: a rope is a bunch of string or thread twisted together to make a bundle that can hold some weight. In the case of suspended scaffolds, the strings are normally wire although other materials such as hemp and polypropylene can be used, depending on the application.

Rope has been around just about forever. Evidence of rope’s use shows up in ancient Asia and Egypt. Wire ropes were invented about 1831 or so by Wilhelm Albert, a German involved with mining. He sought a solution to the very real problem of using chains where the failure of one link meant the failure of the whole chain. By twisting individual wires/strings into small bundles (strands) and then twisting the strands into a rope, (a big bundle), any defects are spread over more components, thus avoiding the problem of the weak link.

The industrial revolution encouraged rapid development of wire rope technology and the use of wire rope continued to increase. In 1841, John A. Roebling, designer and constructor of the Brooklyn Bridge, began manufacturing wire rope in America. Continued research and development discovered that more wires in the rope offered more flexibility and in 1884, researcher Tom Seale developed the parallel strand, where he used different diameter strands to make the rope. Figure 1 illustrates the Seale design.

While iron wire was initially used for metal ropes, steel wire began to be used in the late 1800’s. In fact, steel wire rope was first used in the construction of the Brooklyn Bridge in New York; the main ropes are still in use, demonstrating the durability and longevity of wire ropes. Over time, other wire rope designs have appeared, including the Filler strand, the Warrington strand and the Lang lay rope. Each design has its advantages and the job requirements will dictate the choice.

Wire rope is strong stuff, especially considering its relative light weight. Wire rope load capacity is governed by the rope material, configuration and diameter. While wire rope is available in an almost infinite number of diameters, normal diameters for suspended scaffolds are 5/16 or 3/8 inches. By its nature, rope can only handle tensile loads (you can’t push a rope!). However, the great advantage of a rope is that it can still handle the rated load whether the rope is 5 feet or 500 feet long. Within limits, that means the rope can hang down a 300-foot tall building and still support the same load as the rope will on a 50-foot tall building.

Adjustable suspended scaffolds typically use drum hoists or traction hoists. Drum hoists wind the wire rope on a drum or spool attached to the scaffold platform while a traction hoist passes the rope through the machine. Consequently, a drum hoist and rigging must support the weight of the wire rope while a traction hoist does not.
As with all materials, wire rope, while rather durable, can be damaged by improper handling and use and can also just wear out through continued use. Consequently, suspended scaffold erectors, and users, must be adequately trained in the potential hazards. For example, erectors must know how to handle the wire rope, including how to pay out the rope and how to wind it back up at the end of the job. The rope must be installed so the bottom end of the rope can hang free.

The attachment of the rope to its anchor is obviously critical to the strength of the suspension system. At a minimum, when loops in a rope are being made, a thimble and three fist grips (no u-bolts please) must be used, spaced at the manufacturer’s recommendations. The bolts must be tightened in compliance with the manufacturer’s recommendations; they must be re-tightened after the first loading of the suspension system, and then typically every day after that. The entire scaffold system including the suspension rope, must be inspected prior to each workshift. Properly trained suspended scaffold operators will know to inspect the suspension wire ropes every time the platform is raised or lowered to ensure that the rope is still in useable condition. It is rather undesirable to get the rope stuck in the traction hoist when 100 feet in the air. Even less desirable is having the suspension rope break when 100 feet in the air!

Suspended scaffolds get some impressive media coverage when failures occur since the incident leaves workers dangling high above the street below. Reporters nervously describe the precarious (and assume a dangerous) situation, leading the uninformed observer to believe that these devices are incredibly unsafe and a peril to the users. Since wire ropes on properly designed scaffolds can support six times the expected load, when the scaffold fails, it isn’t because the equipment is hazardous, but rather it is because somebody just plain screwed up. Don’t you be one of them!

5 Essential Facts About Facade Access Design

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Facade design is an important aspect of any building project, but that doesn’t mean simply considering what the exterior of the finished building will look like.

Facade access design is an essential consideration. A good system will allow for maintenance to take place safely and at a reasonable cost. Maintenance operations can include setting up advertising, cleaning windows, fixing damage and more.

Here are five essential things you need to know about facade access design.

There are temporary solutions…

Temporary solutions for facade access include rope descent systems and hydraulic access platforms.

While these are relatively low-cost solutions, they have their drawbacks too. For example, a hydraulic lift will not reach the highest floors of a tall building, while rope descent work can take quite a long time.

… and permanent solutions

To secure a re-usable solution, a range of systems including monorail cradles or fixed davits might be favored depending on the jurisdiction (California, New York and other states have their own set of specific regulations).

Monorail cradles are useful on large flat or curved surfaces – they travel along a rail at the top of the building and can be lowered to the required level for access to the facade. They may not be appropriate to use for more ‘experimental’ facade designs.

For flat surfaces with less width, a fixed davit may be more cost-effective than a monorail cradle. Fixed davits are single arms which sit in one position and are used to raise and lower a maintenance platform.

Whichever of the two solutions you opt for, permanent or temporary, you will need to ensure that there is also a fall protection system to protect the people who are working on the facade.

Equipment needs to be inspected regularly

Just as facades need to be accessible, so does your facade access system so that it can be inspected and tested for safety at regular intervals.

OSHA 1910.66 states that all permanent equipment used to access a facade must be load tested when installed, and visually inspected every year. Additionally, OSHA 1910.27 states that each anchorages must be inspected annually and re-tested every 10 years.

Novel facade design calls for a novel approach

As modern architects create buildings with new and artistic facades, it’s important to think about how the facade will be accessible for maintenance purposes.

Sometimes, this will require an approach which is slightly different from the norm. This must be considered at an early stage of the project.

If the architect’s vision for facade design would result in a building which causes problems for facade access, there may have to be a compromise – or a novel approach.

It’s always good to get a second opinion

Our facade access design consultancy services allow building owners and architects to take advantage of our expert knowledge to create facade access designs that are safe and cost-effective.

We provide turnkey structural design and engineering solutions for new buildings, and can also help retrofit existing buildings to bring them up to code.  Contact Us today to find out how we can help with your façade access project.

I’m Digging Your Shoring Plan!

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Due to the complexity and property line constraints of modern construction, earth shoring requires a solution that must conform to both engineering and safety guidelines during all stages of construction.

Here are the 5 key concepts to remember for an earth shoring design:

1. Applicable codes: The type of project will define the requirements for an engineered earth shoring plan. For instance, a design that allows for inches of deflection at a multi-story urban high-rise may not be compatible with AREMA requirements for railroad earth shoring. While a contractor may be able to get away with using a cantilevered design, a similar design that incorporates the locomotive surcharge loads into the analysis may fail simply by being out of tolerance for railroad deflection guidelines. In this case, the common solution is to add soil anchors to keep the design in compliance.

2. Material: This is typically a contractor preference. If a contractor has a substantial inventory of steel I-beams/H-piles and wood lagging, it is in the best interest of the client for the engineer to design the system accordingly. Piles may need to be spaced more tightly and the design may not be as efficient as sheet piles, but it does eliminate the need for the contractor to spend more money.

3. Sequencing: With most earth shoring designs, there is a sequence of installation that must be followed based on the applied loads that change with depth. For example, in a cofferdam design, if wale frames are required, the contractor may have to install the wale at a specified elevation prior to proceeding. This elevation may be above the final excavation depth, but the engineer should have determined that this is the maximum depth that the shoring can support in a cantilevered condition and/or without restraint at the base. This may be a result of deep excavations where the substrate alone at the base is not adequate to support the lateral load. Oftentimes, many scenarios must be analyzed to ensure that the members are not overloaded and the entire shoring design is code-compliant at any given stage.

4. Embedment Depth: As a general guideline, the minimum embedment depth of a pile must be 75% of the retained height to ensure adequate development and base restraint.

5. Workers at the Top of the Excavation:  While the designer may account for the surcharge loads at the top of the excavation, it is also important to consider the impact of workers. If a guardrail is required based on project conditions, then it must be OSHA compliant and any loads/connections required shall be accounted for in the design of the pile. Common practice is to weld a guardrail post at the top of the pile, but this must be checked not only for load application, but also for maximum spacing.

Engineered shoring plans are critical components of construction plans, and a well-thought out design will save the contractor both time and money. As the saying goes,”Think before you dig!”

5 Impressive Things Built (or Fixed) Using Cofferdams

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Everyone knows about dams. But have you heard about a cofferdam?

Cofferdams have been around for a long time. People have used these when excavating very large plots of land or building foundations of water-based structures such as bridges or piers. The cofferdam keeps water from flowing into these sites, ensuring a dry foundation.

The cofferdam has been used to build and fix some impressive things. Check out the five most inspiring objects constructed by using these fascinating dams.

5 Impressive Things Built (or Fixed) Using Cofferdams

Cofferdams have helped civilizations divert water, gain new territory, build dry structures safely, and even recover history. They can be as simple as a pile of sandbags set up to use as a barrier during wartime or complex as a double sheet piling used in modern-day bridge construction.

While today the cofferdam is particularly useful for earth shoring engineering projects, it continues to be used in the engineering world as a helpful tool in water diversion projects.

1. Battleship U.S.S. North Carolina

Because ships are a water-borne craft, their preservation often depends upon a dry work environment. When it comes to this battleship located in Wilmington, North Carolina, the use of a cofferdam will integrate a memorial walkway for visitors and water-free access to the battleship for preservation and repair work.

The project, nearly six months away from completion, is unique because it won’t rely on the cofferdam for underwater construction. This battleship will be open to visitors and kept looking sharp above water.

While this battleship will cost a hefty $8 million, it will, in fact, be a permanent installment. This is another great aspect of the cofferdam: it can be both temporary or fixed. The permanent cofferdam enables future maintenance and repair work on structures like the U.S.S. North Carolina.

2. The Hoover Dam

It may seem counterintuitive to say that dams are made by using dams. But with this impressive dam that’s become an icon of the American road map, cofferdams were a huge part of the construction.

The Hoover Dam construction was an architectural and engineering feat in Nevada in 1933. Before the dams were installed, workers removed 250,000 cubic yards of silt from the river in order to ensure a solid starting foundation.

Two cofferdams were required to make sure the construction was dry and water-free. Both were made from earth and rockfill, and relied on an additional rock barrier to prevent any additional water seepage. While some people were worried that the spring Nevada floods may damage all of this foundation pre-work, the damming worked and construction went along as planned.

3. Ancient Roman Bridges

When we said that the cofferdam has been around for a really long time, we meant it. For thousands of years, civilizations have found the cofferdam useful, and you see this in many of the bridges of Ancient Rome.

Early populations relied on more basic forms of the cofferdam in order to control waters for drinking supply, irrigation, and land control. Often this entailed the diversion of a river. Legend has it that King Cyrus of Persia used the cofferdam in order to divert the Euphrates River in his pursuit of the city of Babylon. This meant that an entirely new empire was established based off of the use of this dam alone!

Similarly, the Romans made use of this handy type of damming when bridging the Danube River. Trajan’s Bridge, built as a result of cofferdam wood pilings, enabled the Romans to travel to contemporary Romania. This bridge totaled nearly 4500 feet in length.

4. The Tapan Zee Bridge, New York City

The Tapan Zee provides a great example of how cofferdams still help with important construction feats today. This incredible bridge spanning the Hudson River cost nearly $4 billion to construct. Its completion would not have been possible without the use of the cofferdam.

A complex software was used to design the steel dams, 90 feet by 45 feet, used in construction. The software also took soil type into consideration. Because the Hudson contains a lot of river silt and soft deposits, the Tapan Zee dams had to be backfilled in order to create a solid base for the bridge piers.

5. The La Belle ship

The La Belle shipwreck has long been an icon of the Texas coast, and the cofferdam made sure that La Belle remained a fixture of seventeenth-century history.

In 1687, this ship crashed along the shoreline as a result of poor weather and difficult seas. Manned by a New World explorer, this ship was the last of four ships sent to explore the unknown coasts. When La Belle crashed and sank, it became sealed in mud for over three hundred years.

In 1995, an archeological team discovered the site of La Belle’s sinking. Such a recovery requires a lot of complicated engineering. The Texas Historical Commission constructed a cofferdam system around the sunken ship. This elaborate system cost over $2 million.

The mission was successful, and in 1997 the full extent of the treasure was known. Hundreds of incredibly preserved artifacts and much of the ship’s original structure were recovered. If it weren’t for the cofferdam, we would never know this history.

Cofferdams of the Future

There’s no doubt about it: the cofferdam is versatile, useful, and amazing. It has enabled people to bring history back to the surface, cross rivers, and construct impressive architecture. The cofferdam will continue to be an essential part of contemporary engineering projects.

At DH Glabe & Associates, cofferdams are our bread and butter when it comes to earth shoring engineering. To date, we’ve completed over five thousand company projects in thirty-two years, relying on the expertise of over fifty professional licenses. We assist with both civil and commercial projects using a variety of technology, including H-piles, mechanically stabilized earth walls, sheet piles, geofabric, and secant pile walls.

Earth shoring is not all we do. No matter the size or type of your engineering project, at DH Glabe & Associates we pledge to be with you every step of the way. Contact any of our construction engineering experts today to learn about what we can do turn your project into a reality this year.