Friday, October 7, 2016

ASCE 7-16 launches early 2017

ASCE 7-16 will be online in early 2017 and it looks like it will be a smooth transition with 7-10 and 7-16 available online with side by side provisions and commentary as well as redlining changes from 7-10.


Watch the video which seems to be geared towards the next generation of younger engineers
ASCE 7-16 video here


as well as this video with a preview of changes



Wednesday, August 31, 2016

Arcitc Module Design

Currently working on the structural design of a module which will be transported by truck to the North Slope of Alaska. The design was carried out with the clients specifications which require the use of ASCE 7 for design loads. In addition to ASCE 7 the client specified frost jacking and adfreeze strength from permafrost for the vertical support members. Additional considerations into snow drift loadings were carried out as well as windward and leeward wind forces on the structure. Point loads were added for valve and piping dead loads.






Thursday, August 25, 2016

Kennedy Fracture Critical Inspection



Last week I made the trip down to Louisville KY to assist with the Kennedy Bridge Fracture Critical Inspection. The trip got off to a rocky start with multiple flights being delayed and I spent about 14 hours stuck in the Denver Airport.


After getting to Louisville we were able to get started on the inspection despite a couple days of iffy weather that consisted of fog and scattered rain showers. On days that did not rain we were able to inspect the upper chord and diagonals. The lower chord, floorbeams and general photos were left for rainy days.


We were able to efficiently move throughout the structure only being delayed by locations that required NDT. We worked in groups of two or three, each group carried mag particle (MT) with them as to reduce the load on each climber while still being able to confirm deficiencies.















Monday, August 8, 2016

Loading Dock Seismic Analysis

Currently working on the seismic analysis of a loading dock in Alaska. Using RISA 3D I have been able to construct a 3D model using existing plans from the 1960s. The model is very detailed to capture the necessary dynamic properties with lump masses to represent dead loads not captured.


I'll update this as I have time to include more information






Monday, June 6, 2016

Passed the PE


After hundreds of hours of studying spread across four months and an 8 hour exam, I found that I have passed the PE exam. Now I am officially a Professional Engineer in Alaska.

 

Tuesday, October 20, 2015

Sherman Minton Bridge Inspection

Copied Info from Wiki until I have time to update this post about our inspection


The Sherman Minton Bridge is a double-deck through arch bridge spanning the Ohio River, carrying I-64 and US 150 over the river between Kentucky and Indiana. The bridge connects the west side of Louisville, Kentucky to downtown New Albany, Indiana.




History[edit]
In 1952 the "Second Street Bridge" was reaching peak traffic, and the K&I Bridge faring similarly. Arthur W. Grafton commissioned two studies in 1952 and 1953, with their results being a need for two bridges in Louisville; one crossing to Jeffersonville, Indiana, and the other to New Albany. Hoosiers as far as Scottsburg, Indiana (30 miles (48 km) away) were vastly against making any bridges toll, and many residents of Louisville were against toll bridges as well.[1] When the Interstate Highway System was announced by President Dwight D. Eisenhower, the solution became clear. The Federal government would finance 90% of both bridges, with Indiana paying 10% of the New Albany bridge, and Kentucky paying 10% of the Jeffersonville bridge.[1]
The New Albany bridge was given to Hazelet & Erdal, of Louisville to design in 1956. Construction began in June 1959, and was completed in August 1962. It was built at a cost of $14.8 million. In December 1962 Indiana governor Matthew E. Welsh announced it would be named for the former United States Senator and Supreme Court justice Sherman Minton, who was a native of New Albany.[2] The American Institute of Steel Construction in 1961 named it the most beautiful long-span bridge of the year.[1]



 View of the bridge from the Main Street in New Albany
On February 5, 2009, a fifteen container coal barge lost power and was pushed downstream by the current and struck the bridge's central pier. The Indiana Department of Transportation (INDOT) closed the bridge for several hours while it was inspected for damage. When no damage was found, the bridge was reopened later the same day.[3]
Closure of 2011-2012[edit]
On September 9, 2011, Indiana Governor Mitch Daniels ordered the bridge closed. This was done after construction crews found cracks in the main load-bearing structural element. Experts from INDOT, the Kentucky Transportation Cabinet (KYTC), the Federal Highway Administration (FHWA), and private engineering firms and academic institutions participated in determining the severity of this crack and others found on the bridge, and determine whether the bridge could be saved.[4][5][6]


It was initially feared the bridge would remain closed from several months to up to 3 years, and that the entire span would have to be either completely replaced or extensively renovated before the Sherman Minton Bridge could reopen to traffic. However, engineers determined the crack that initiated the bridge closure dated back to the bridge's original construction in the 1960s, but had not been discovered until the summer of 2011 because another structural component was covering it. On September 23, 2011, Kentucky Governor Steve Beshear and US Secretary of Transportation Ray LaHood announced the 2.5-inch crack has been repaired, but the bridge would remain closed until crews completed an inspection of the remainder of the bridge.[7] Five to seven additional cracks were discovered during the following inspection in welded areas in a load-bearing steel beam. "The fissures were discovered in a type of steel frequently used in the 1950s and 1960s that is now known to be susceptible to cracking. ...". This necessitated the bridge being closed for an extended period of time for repairs. Repairs cost $20 million and ultimately took four months to complete.[8]
In a news release from the Indiana Department of Transportation, dated October 18, 2011, Governor Mitch Daniels announced that Louisville based Hall Contracting of Kentucky had been awarded the repairs contract in the amount of $13.9 million. A time frame of 135 work days was announce with an incentive of $100,000 per day to finish early. Likewise, a penalty of $100,000 would be deducted from the contract payments for each day over. Repair cost were covered by the Federal Highway Administration, who announced on September 30, 2011 that it would contribute 25% of the cost, with the remaining 75% being equally split between Indiana and Kentucky.
The contract attached 2,400,000 pounds (1,100,000 kg) of reinforcing steel plating along both sides of the bridge ties spanning 1,600 feet (490 m). The repairs along with regular maintenance increased the bridge's safety and reliability and extend its useful life by at least 20 years.[9]
Repairs were completed and the Sherman Minton Bridge reopened at 11:50 pm on February 17, 2012.[10]


Construction[edit]
The bridge is a double-deck configuration—westbound traffic from Kentucky to Indiana travels on the upper deck of the bridge, while eastbound traffic from Indiana into Kentucky travels on the lower deck of the bridge. It is of similar construction to the Hernando de Soto Bridge in Memphis, Tennessee (but the de Soto Bridge is single-deck).
The steel used was T1 steel, which in the early 1960s was "innovative material" but is much weaker than modern steel. Classification of the bridge is "fracture critical" because if one part of the bridge should fail, the entire bridge could be at risk.[11]






 










References[edit]
 Wikimedia Commons has media related to Category:Sherman Minton Bridge.
1.^ Jump up to: a b c Kleber p.123
2.Jump up ^ Kleber pp.123,418
3.Jump up ^ Mike Dever (2009-02-05). "Sherman Minton Bridge Reopens". WAVE 3 News. Retrieved 2011-09-12.
4.Jump up ^ "Sherman Minton bridge shut down; crack found in bridge". Louisville, Kentucky: WDRB. September 9, 2011. Retrieved September 9, 2011.
5.Jump up ^ "Sherman Minton Bridge closed indefinitely due to structural cracks". Louisville, KY: The Courier-Journal. September 9, 2011. Retrieved September 11, 2011.
6.Jump up ^ Barrouquere, Brett; Cappiello, Janet (September 12, 2011). "Traffic nightmare over closed Ohio River bridge". Associated Press. Archived from the original on August 20, 2014. Retrieved September 12, 2011.
7.Jump up ^ LAHOOD: One Sherman Minton Bridge crack repaired; no timetable for re-opening WDRB-TV, Sept 23, 2011
8.Jump up ^ "Sherman Minton Bridge repairs to take six months, cost $20M". The Courier-Journal. October 1, 2011. Retrieved October 1, 2011.
9.Jump up ^ "Sherman Minton Bridge Repair to Require 135 Work Days" (PDF). Indiana Department of Transportation. Retrieved 27 October 2011.
10.Jump up ^ http://www.corydondemocrat.com/Articles-i-2012-02-21-224052.114125-Motorists-celebrate-bridge-reopening.html
11.Jump up ^ "Agency: Sherman Minton Bridge's Steel More Brittle". Associated Press. 12 September 2011. Retrieved 12 September 2011.
Kleber, John E., ed. (2001). The Encyclopedia of Louisville. University Press of Kentucky. ISBN 0-8131-2100-0.

Monday, June 29, 2015

Wrapping up my Masters Degree


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

Tunnel Overhead Inspections



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

Kennedy Bridge Pin Testing

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

Corrugated Steel Low Profile Arch Load Rating

Recently I finished a load rating for a corrugated steel low profile arch which carries a rural road over a small brook. Unlike the recent masonry and concrete load ratings I have worked on, this load ratings was not as cumbersome. The rating criteria is much more straight forward with the codes that are currently in place. Much like the arches this structure can be analyzed using a column earth load and a live load which is distributed through the depth of the earth fill. We were able to model the live load action thru the earth fill using STAAD and creating influence lines.

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.