An unexpected location for falling danger, anchorage was the failure point here.

Previously, on Battlestar Galactica: …Ah, sorry, perhaps a little too much television lately.  In our last article we were discussing the harness and anchorage system within fall arrest.  Today we discuss the connectors and decelerators in fall arrest, cover fall restraint, and dabble into conclusions on fall protection in general.

The connector is the item which links the harness to the anchor.  This element is usually a rope which can be either lifeline rope or static rope.  Lifeline rope is designed to stretch when in tension, so that some of the energy of the fall is absorbed by the stretching.  Static rope does not stretch, and is designed to reduce falling distance.  Depending on the requirements of the site, either may be used, as long as the fall is stopped without damaging the person.

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Fall Protection

The dangers of falling can be found in the most unlikely of places.

“Better safe than sorry.” – American Proverb

To the masses of Joe Publics walking down your city streets every day, fall protection may only include mittens and a scarf, but it is important for those working at heights to know the important difference between the protective measures required for a chilly breeze as opposed to a large vertical plummet; if you have ever worked in high places then you too have had the ever-creeping fear of slipping and going splat grow in the back of your mind.

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Although there is the odd deviant, obeying the law is important!

The Laws of Tendering

“Law is a bottomless pit; it is a cormorant,–a harpy that devours everything” – Jonathan Swift (1667-1745) prophesizes the current condition of Engineering Law and Ethics as taught at any major university.

For those of you engineers out there reading this blog, you too had to sit through a law course in your undergraduate career. If there is as much similarity between this writer, his old classmates, and the rest of the engineering demographic in the known universe as can be reasonably assumed, then engineering law and ethics was the class we all skipped in our desperate attempts to get a decent passing grade in concrete and steel. With that in mind, this article will cover the section of course notes on tendering that we burnt after the final exam, which perhaps is more interesting to all of us now that we have to be professional engineers while avoiding being sued by everyone under the sun.

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The Future of Green Engineering

Figure 1: One of the world's first sustainable engineers

In recent years, focus has been shifting towards changing our behaviour to be more sustainable and environmentally friendly (read: greener). You may have surmised that land development and construction have not been spared from this new initiative. So how does this new mindset change the way we design, construct, and operate new buildings?

One of the main goals of sustainable design is to improve on efficiency [1]; this efficiency can manifest itself in different aspects of a building. For example, it may change the way building design, construction, and day-to-day building operations are approached. When talking about efficiency, we generally refer to how effectively resources are used.

Green Roofs

Some features seen on sustainable building include green roofs, which reduces the amount of water run-offs, solar panels and solar water heaters, which help harness renewable energy and reduce dependence on fossil fuels, reflective building surfaces, which reduces the amount of energy absorbed by the building and thus energy expended into controlling building temperatures, and high quality insulation which also help on reducing energy consumption.

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Part 1 – Part 2 – Part 3 – Citations

In this amazing bridge demolition blog post there are several references that were studied that helped compile this post.

They are listed below.

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Complete Bridge Demolition

Shoring Towers to OWSJ

“Blow’d up real good.” – John Candy

Part 1 – Part 2 – Part 3 – Citations

Common Bridge Demolition Processes for Entire Removal

When a bridge is to be replaced, the original bridge must be removed so that the new one may be constructed. Various methods exist for the removal of large structures, inclusive of heavy impact breaking, hydraulic shearing, staged removal, and explosives.

Heavy impact breaking [2] is a common method for demolishing large portions of a structure. This type of demolition is commonly used by either large scale pneumatic drills (Figures 7 and 12), or a ball-and-crane set up (Figure 13), where a large mass is swung or dropped onto the structure to break it up into pieces (helicopter mounted balls and rig mounted “whiphammers” also exist, which involve a restrained arm attached to a spring, that releases blows onto a structure at high speeds). Ball-and-crane demolition in specific is very dangerous because if the crane misses the ball may swing wide enough to tilt the crane over (Figure 14). Heavy impact breaking is popular because it is simple and can do massive damage, however it is not effective for structures surrounded by people or attached to other structures because it can create large clouds of dust, loud noise, and large vibrations. In addition, for structures with stressed tendons, heavy impact breaking is dangerous because uncontrolled dislodging of the tendons can be hazardous when they lose their anchorage and snap. Furthermore, impact breaking may have difficulty cutting reinforcement, thus requiring cutting in sequence with the breaking.
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Selective Bridge Demolition

Part 1 – Part 2 – Part 3 – Citations

“Do not remove a fly from your friend’s head with a hatchet.” – Ancient Chinese Proverb

Diamond Cutting Saw

Common Selective Bridge Demolition Processes

Selective demolition involves removal of part of the structure which is to be replaced. This process may take the form of cutting or mini-blasting. Cutting bridge sections is a measure of demolition in which parts of the bridge are cut out for replacement and many methods for doing so exist. Mini-blasting involves dislodging parts of the structure with small explosives. Depending on demolition requirements, wire cutting, diamond sawing, splitting, jack-hammering, abrasive water jetting, or mini-blasting may be used.

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Never play cards with the Joker

A Beginner’s Guide to Bridge Demolition

Part 1 – Part 2 – Part 3 – Citations

Introduction

“I’m a simple man. I like dynamite, and gunpowder, and gasoline!” – The Joker.

With the growing number of engineering services available today, it’s easy to do some realistic comparisons. This article provides some great tips and helpful hints as it applies to why using an engineer is the safest way to demolish bridges. Whether its complete bridge demolition or selective demolitions complete control and predictable outcomes is synonymous with safety. This article will be published in 3 parts for you to enjoy. It will include some pretty wild videos that illustrate demolition done properly and demolition gone bad. Here is the introduction.

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