Weathering Steel Multi-Girder Rating

Started the new job last Monday and jumped on a rating right away.

The rating is part of a contract for RIDOT and is a steel multi-grider system with a composite deck. The bridge is located in downtown providence and spans 102 feet over the Woonasquatucket River.

First I calculated the dead loads and live load factors and then I moved onto setting up the BRASS-Girder input file.

The bridge had for bays with different types for utilites which made selecting which girders to rate a little more difficult.

Its been over a year since I last used BRASS so I had to shake out some of the rust (lots of errors and looking up most of the input order). After about three tries I was finally able to get it to run correctly.

Newport Bridge Inspection

This coming week I will be down in Newport RI to inspect the Pell Bridge. This will also be my last week with WSP Sells, as I start my new job with Michael Baker Engineering on the 3rd. 

The Pell bridge carries RI Route 138 from Newport to Jamestown and has a structure length of 11,247 feet with a maximum span of 1,601 feet. at the highest point the deck is about 200 feet above the water and over 400 high at the tops of the towers. luckily I'm not afraid of heights!
The past few weeks the bridge has been inspected from water level on a barge with an 80 foot manlift. This coming week we will be using two 62 foot snoopers (under bridge inspection units). We will be able to see about 2/3 of the underside from our first setup and later able to inspect the remainder from the other side.

From what I've heard the Pell has the longest suspension span in New England and is ranks 75th in the world.

Pedestrian Overpass

This past week I completed the inspection for the India Point pedestrian overpass in Providence RI. The bridge allows foot traffic to cross over I-195, Ramp EI and India Street. The bridge give access from the Eastern half of Providence to cross I-195 to a small park on the water.

The bridge was built in 2008 and has a total structure length of 250.9 feet with a maximum span of 91.2 feet (over I-195). The maximum span consists of concrete butted box beams.

The top of the bridge consists of stone pavers, vegetated garden lighting and seating. During the inspection we noticed that the bridge had an unusual amount of water draining at one corner of the bridge. My only assumption would be from the irrigation for the gardens. Hopefully this does not continue to leak and cause damage to the structure. 

Bike Path Thru Girders

The past two days I was out inspecting two bridges which were converted to carry new bike paths instead of railroad lines.

Since the bridges were both rehabilitated recently they were a breeze to inspect. Other than gouges along the bottom flanges, the bridges were in excellent shape. Both bridges were simple spans consisting of built up thru plate girders.

It was also nice to have friendly people riding by instead of the typical motorist who shouts motivational words as they pass.



Critical Finds

This past week I was busy with bridge inspections in Rhode Island and worked about 90ish hours in five days. The week started off hot and muggy and was made even worse when I started finding broken welds in our first shift and then section loss holes in beam ends in my second shift.

This continued for most of the week and was really making me question the integrity of the past inspections. Both the state and federal government QC the actual inspection reports and do a great job making sure the provided information makes sense and correctly identifies the condition of the bridge but should they go one step further and field check some bridges too? Should consultants be rated on the accuracy of their field investigations?

I've also noticed that some of the past inspection reports from different consultants have started to take a "lazy" approach to writing a report. Instead of writing the conditions they observed they state that the conditions are generally the same as the past inspection. I feel that an inspection report should convey the current conditions of a bridge and not the conditions observed in the past.

Well that's enough venting for now, I meant to write about the process of critical finds but was side tracked,  I'll post pictures and bridge information for the past month or so this coming week when I have a nice and easy 40 hour week.

Rolled Steel Beams

The past two weeks I've been very working on the routine inspection of the Huntington Viaduct in Providence RI. The rolled steel beam superstructure with composite concrete deck spans across Route 10, AMTRAK and a lot of grass.

After this week when I have time I'll update with photos and more info but for the time being I need to crash since this will most likely be a 90 hour work week. 

Arch Design

The past few weeks I've been busy helping with the design of a few bridges. A few weeks ago we submitted our 90% bridge design for five bridge in western Mass. Two weeks ago we submitted our PS and E for an Inverset bridge up in central Mass. This past week we were very busy trying to get our 90% bridge design and 100% highway design finished.

Unlike the bridges in western Mass I was only able to design a few components of the arch in south eastern Mass but helped a lot with the drawings.

A taste of the designs which I accomplished this past month:

U-Wingwall

Curtain Wall

Backwall

Elastomeric Bearing

Retainer Plate

Bridge Rail

Pedestal

Chamber

Seismic

Thermalmovement

Drainage

Piece Weights for Precast Abutment backwall, stems and footings

Fracture Critical Bridge Inspections

So after a couple buys months of design work, I'm back on inspections.

While I was in the office, a few others were out in the field complete fracture critical inspection which were held up with paper work discrepancies between RIDOT and AMTRAK.

Right now I'm trying to do my best to help complete a few of the reports. The reports end up being slightly easier than a routine or inventory inspection since they focus on only the fracture critical elements of the bridge.

A fracture-critical bridge is one that does not contain redundant supporting elements. This means that if those key supports fail, the bridge would be in danger of collapse. This does not mean the bridge is inherently unsafe, only that there is a lack of redundancy in its design. -From AASHTO

Fracture critical members a usually defined by having an AASHTO fatigue detail or category which is greater than C (A being low and E being high risk).

Typically bridges such as steel trusses, thru girders and steel pier bents contain fatigue details which are greater than a C.

Bridge  1

  Bridge 2  

 Bridge 3  

 Bridge 4  

Bridge 5 

Bridge 6 

  

Bridge 7 

 

Bridge 8