Monday, June 29, 2015
Its been a busy 18 months but I'm finally wrapping up my Masters of Civil Engineering with a Structural concentration. Just need to finish my Capstone Project, which will be a three hinged glulam tied arch that will carry the Appalachian Trail over the Kennebec River in Caratunk Maine.
Sneak peak of the design so far:
Hydraulic using HEC-RAS
Preliminary Structural Analysis using Visual Analysis (will hopefully be able to use MidasCivil for a refined analysis)
Monday, June 15, 2015
Since the Tunnels in Boston are congested during most hours of the day inspections which require lane closures need to be done between 10pm and 5am. The typical closures we have been working in go out at 11pm and we need to be out of the closure by 4am.
This doesn’t leave us a lot of time to finish out inspections so we are usually very organized and prepared to inspect before we enter the closure. Most notes are refined down to a check list and previous tables of deficiencies are used to keep track of changes. Since our inspections for this assignment are just overhead inspections we spend a great deal of time looking at the lighting supports, panels and hangers. We look at all the overhead items but these tend to be the elements which have the most notable deficiencies. We also need to inspect the hangers which are located in the exhaust plenum. The exhaust plenums are often very dirty and cover us in soot, which is why we wear tyvek suits to protect our fancy field clothes.
Friday, June 12, 2015
After our In-depth inspection of the Kennedy earlier in the year, we had to test the pins. Using non-destructive testing (NDT), to be more accurate ultrasonic testing (UT) we were able to verify that our visual inspection was correct and there were no deficiencies. Using rope access we were able to access the pins without the need of traffic control or heavy access equipment.
Monday, June 8, 2015
The field verification inspection was very straight forward and now issues were found. The details from the plans were verified and no changes were needed. Issues that could have arose would be a flat or reverse curvature in the corrugated section which would show that the structure is either under designed, it has seen a load which was much greater than it was designed for or that the earth fill could be eroded leading to the live load not being distributed. To inspect the structure and give myself a little more practice I decided to use rope access instead of carrying down ladders through the 4 feet of snow still surrounding the bridge.
Wednesday, June 3, 2015
The Hernando de Soto Bridge is a through arch bridge carrying Interstate 40 across the Mississippi River between West Memphis, Arkansas and Memphis, Tennessee. Memphians also call the bridge the "New Bridge", as it is newer than the Memphis & Arkansas Bridge (carrying Interstate 55) downstream, and the "M Bridge", due to its distinctive shape. It is of similar construction to the Sherman Minton Bridge between Louisville, Kentucky and New Albany, Indiana.
At night, the bridge is illuminated by 200 sodium vapor lights along its "M" shape structure. The bridge was first lit on September 5, 1986, after $373,000 of private funds had been raised to fund the cost and installation of the lights. Due to some river traffic having issues with the lights at night reflecting on the water, the city installed a remote switch to toggle the lights on and off briefly while the vessel passes under the bridge. During the 2011 Mississippi River floods, the bridge became dark for about 2 months because the transformers that supply the electricity for the lights were removed to prevent damage to them by flood waters. The bridge was re-lit in a ceremony which occurred on June 21, 2011.For our inspection we had to turn the lights off each day and turn them back on after we were finished.
The weather varied from 80F sunny to 34F with sleet. With varying weather we had to pay close attention to the radar and incorporate it into our rescue plan.
One of the days the Memphis Fire Departement came out to see how we can access the bridge by rope access. We were able to answer questions they had and they were able to talk to us about their rescue capabilities.
Tuesday, March 3, 2015
Thursday, February 19, 2015
Thought I'd start to post some of my rope access techniques/skills, I'm sure some other engineers might be interested in learning some rope access techniques/skills for when access is limited.
Here I'll quickly discuss the Bowline knot, which I use often for rope access, hiking and kayaking. CMC Rescue posted a great video on how to tie the bowline knot and you can watch it below. Usually seeing a knot being tied is much easier than reading how to do it.
The Bowline (ABOK # 1010, p 186) makes a reasonably secure loop in the end of a piece of rope. It has many uses, e.g., to fasten a mooring line to a ring or a post. Under load, it does not slip or bind. With no load it can be untied easily. Two bowlines can be linked together to join two ropes. Its principal shortcoming is that it cannot be tied, or untied, when there is a load on the standing end. It should therefore be avoided when, for example, a mooring line may have to be released under load.There are a few variations of the bowling knot:
- With a Safety Knot either in the Loop or Line
- Yosemite Tie-off
- Eskimo Bowline
- Left Handed Bowline
Monday, December 29, 2014
A few weeks ago I attended a Society of Professional Rope Access Technicians (SPRAT) training course in Bristol RI at Axcess Rescue for my SPRAT Level II certificate. This means that the past year and half I have accomplished:
SPRAT LEVEL II (LEAD TECHNICIAN)
- Minimum of 6 months and 500 logged rope hours as a SPRAT level 1 (verification of SPRAT log book should be acceptable).
- Complete a four-day rope access training course from a qualified trainer (recommended, not required).
- Complete a level 2 written test
- Level II Field evaluation by an independent SPRAT Evaluator on day 5.
At the training I was able to learn the follow:
- Management and communication awareness
- Job Safety Analysis proficiency
- Principles of mechanical advantage systems
- Load sharing anchor mastery
- Pull-through anchors
- Rope systems analysis
- Cross hauling – (platform and pitch head)
- Rescue hauling – (platform and pitch head)
- Aid climbing
- Pick-off rescue with victim in ascent
The rope access course reviews all level I skills such as:
- Equipment use and inspection
- Job Safety Analysis awareness
- Level 1 Knots
- Back-up device use and handling
- Use of ascending system for ascent and short descents
- Use of a descender for descent and short ascents
- Use of work seat/Bosun’s chair
- Passing Knots in ascent and descent
- Rope-to-rope transfers
- Negotiating a rope deviation (redirect)
- Short rebelay
- Long rebelay
- Negotiate an edge
- Installing and Passing Rope Protection
- Configurations and Strengths of Simple Structural Anchors
- Awareness of load-sharing anchors and force magnification charts
- Climbing with shock-absorbing Lanyards
- Belaying – Methods and communication
- Lowering a load with a two rope system
- Pick-off rescue with victim in descent
- Theoretical rope concepts such as fall factors, safety factors, min. breaking strengths, and safe working loads
A great part about the training was being able to see Level IIIs train next to me. Hopefully in a few years I will be in their shoes going for my Level III. The second part the was useful about the training was the Axcess Rescues instructor has been a big part of the SPRAT organization and has help mold and shape it into the organization it is today.
A great way to stay fresh or learn new rope access techniques are the great videos that are posted on youtube. They walk you through the techniques as if you were in the course.