Concrete Encased Steel Beams

A few weeks ago I did a routine inspection of a concrete encased steel beam bridge. The bridge is located in Tiverton RI. The five concrete encased beams span 35.1'. To access the underside of the bridge we used a small boat which halfway through the inspection sprung a leak. The remaining time was spent in waders, which happened to also have leaks. 

The beams exhibit spalling to the encasement along the undersides exposing the steel bottom flanges. The exposed steel bottom flanges have areas of section loss up to 44% of the original thickness. We were able to find the remaining thickness with a D-meter after spending some time cleaning the surface and making it smooth enough the get a reading.

The concrete deck has several spalls in each bay with exposed and severed rebar.

Just upstream from the bridge there is a spillway with a fish ladder. The damned off pond has large schools of fish and it was a crazy site since they were probably farmed fish and were not afraid of people.

Concrete two Cell Culvert

Currently working on an inspection report of a two barrel concrete box culvert I inspected a couple weeks ago. 

The inspection started off a little hairy with our inspection van getting stuck in mud and soggy grass next to the highway. We attempted to get it out but after a lot of effort we were able to get it more stuck. Next we called a tow truck to help us get out.

While waiting for the truck we started the inspection. The previous inspection noted only 12" of water but when we arrived at the channel we noticed that recent rain had elevated to water depth and was nearly 4 feet deep. So instead of wearing hip waders we opted out for full waders.

With flashlights in hand we started down the 250 foot long barrel. At the end we noticed downed trees partially blocking the inlet. The second barrel was completely clogged and we had to back track down the first barrel to gain access to the second.

The second barrel was much deeper and had a faster flow with white water at the clogged end.

The high water might have also hurt the local animal community.

 

Jumping on the Christmas train.

Okay so it has been a little while and I have honestly not been too busy with work but I have been pretty busy enjoying life. For me that means a lot of doing stuff outdoors (biking, skiing and even joined a rock gym too). 

 

An engineer playing with legos and wearing a star wars shirt, it seems so out of place right! 

Since these only take a few minutes I figured it was time to make an update again.

Just wrapping up a few inspection reports for RIDOT. Currently wrapping up a prestressed concrete I-beam ramp located in East Providence.

The I-195 off ramp has severe deterioration to the pier caps and columns. Timber cribbing was added a few years ago. The concrete I-beams have a few locations of spalling with sections loss to the exposed rebar and stirrups.

The best part of the inspections was that the bridge was near my favorite pizza place in Providence Fellini's.

Iway - Proposed changes to city streets

RIDOT and the City of Providence have been working together to make a plan for the areas downtown once the old I-195 corridor is demolished. With the input from the public the DOT has come up with a nice layout for the post demolish areas.

Demolition of the old highway is wrapping up now and reconstruction of city streets a few were bisected by the construction of the original highway and will take place in 2012.

The following are pictures of the design maps presented at the public meetings and text from their website..

Wickenden Street/East Side Plans

Most recently, RIDOT has selected Alternative 2 among three proposed alternatives for reconfiguration of Wickenden and South Main Streets near the old highway. Revisions to the original proposal include:

•Reduce the number of lanes on the South Main Street (I-195 west-Exit 2 Off-ramp) approach from 4 to 3 lanes.

•Eliminate the channelized right turn lanes from Point Street (east) to South Water Street (south) near Corliss Landing.

•Reduce the width of the median on Wickenden Street to 12± feet. Providing a median on Wickenden Street is the best way to enhance pedestrian safety. The median will provide refuge for pedestrians who do not, or cannot cross the entire width of the street in one phase of the signal sequence. The median will be landscaped and will provide an aesthetically pleasing separation to opposing traffic.

•Eliminate the eastbound left turn lane on Wickenden Street to South Main Street (north).

•Open Benefit Street south of Wickenden Street to one-way southbound through traffic.

•Provide bump-outs at the intersections to enhance pedestrian safety by reducing the crossing distances.

•Route the shared-use path along the southerly sidewalk of Wickenden Street rather than in the median.

The following are RIDOT's thoughts regarding suggestions raised during the public process that are not being adopted:

Intersection at South Main Street and Pike Street:

The volume of traffic using the off-ramp to South Main Street (Exit 2) is significant. The traffic flow will be continuous in the morning rush hour.

Attempting to provide a safe pedestrian or vehicle crossing of South Main Street at this location would require a traffic signal.

There is not enough distance between the end of the interstate off-ramp and the intersection to allow drivers coming off the ramp to perceive a signal and react to it.

There is concern that a signal at this location would cause traffic to stop on the off-ramp and create congestion on the interstate. This will conflict with many of the improvements being realized with the Iway project. Moreover, having vehicles stopped beyond the off-ramp and on the interstate would expose them to rear-end crashes.

Left turn from westbound Wickenden Street to South Water Street (south):

Significant congestion would likely be caused on South Water Street, Point Street and Wickenden Street through Fox Point if this left turn is allowed. The current intersection configuration has three lanes in the westbound approach and a by-pass right turn lane in the eastbound direction. These will be eliminated with the redesigned alternative (Alternative 2).

The proposed alternate route for traffic destined to South Water Street (via South Main Street and Dollar Street) is only two-tenths of a mile, less than a one minute drive. This time and distance is insignificant considering the average trip for vehicles passing through this intersection.

Left turn from India Street (north) to Point Street westbound and pedestrian/bicycle crossing at India Street:

There is not adequate sight distance because of the vertical crest and horizontal curve caused by the Point St. Bridge to make a safe left turn out of India Street. Most vehicles exiting the India Point Park and waterfront area can conveniently use the new South Main St., which is signalized at Wickenden St.

Crossing Point Street would not be safe for pedestrians because the crest on the Point Street Bridge does not give drivers or pedestrians adequate sight distance.

West Side Plan Changes

Revisions to plans for areas west of the Providence River along the old highway corridor include:

•Elimination of proposed Eddy Street between Ship Street and Clifford Street.

•Accommodations for bicycles on all the new sections of streets.

•A mid-block pedestrian crossing across Dyer Street between Ship and Dorrance Streets to provide access between the new park and the Downtown and Jewelry Districts.

•Eddy Street will be three lanes wide with bike lanes in each direction. Dyer Street will be three lanes with bike and parking lanes in each direction.

Rebuilding the Pawtucket River Bridge

RIDOT is currently replacing the Pawtucket River Bridge, which carries I-95 over the Seekonk River in Pawtucket. The bridge currently is posted at 18 tons, forcing trucks to use alternative ways such as I-295,  Route 146 or local detours on the city's streets.

A total of seven bridges will be rehabilitated as part of this $81 million project. The bridges will be constructed in phases and soon the posting will be removed.

Currently when I drive over this bridge there are two state troopers at each end waiting for trucks over the weight limit to pass over. The fine is a few thousand dollars to the driver and not worth the risk in my mind at least.

RIDOT announced the other day that it has started construction of three steel arches for the first part of the Pawtucket River Bridge replacement.

Using prefabricated sections of steel will make for a faster onsite construction time. They estimated that it will only take two weeks to complete the construction but I think with this winter weather heading in it might take a little long

The next phase of the $81 million project will involve demolishing the existing I-95 North bridge and building a new structure in 2012. RIDOT will then shift I-95 South traffic to that new span, a step that will completely eliminate the 18-ton weight limit on the Interstate. Construction will continue with the demolition and reconstruction of the third major span, after which RIDOT will remove all traffic shifts on the highway. The bridge being built this fall will remain in service and be used for traffic entering and exiting the highway from George Street and School Street. -From RIDOTs website

Flickr Photos From RIDOT

I-195 Demolition in Providence Slide Show

Not much of a post but saw this slide show online and thought it was pretty cool showing the demolition of most of the I-195/I-95 interchange in Providence while they were putting in the Iway.

Demolition Slide show

RIDOT Finally Opens Iway Ramp

 

So a while ago I think I wrote about inspecting a ramp and how we found pier columns with extensive cracking before they had been opened for traffic.

After non-destructive testing was done they found out that one column had significantly lower compressive strength than the design called for.

The ramp was not opened and repairs were ordered. The superstructure was braced with shoring and the top of the concrete pier column was taken done to the reinforcement and the concrete was placed again.

The other week when I was in the area I noticed that the ramp was opened October 3rd to all traffic and was the last ramp to open for this project.

Steel Multi-Beam with Cover Plate Rating

Started my second rating today. The bridge is located in Newport RI and is near "THE" Newport bridge which I inspected a few weeks ago.

The bridge consists of ten rolled steel beams which span 86'-1" and carries RI 138 with a composite concrete deck and asphalt wearing surface. The bridge has a line of summitry along the median which made the rating slightly easier from a ten beam system to two five beam systems. I ended up choosing a typical exterior and interior beam and both fascia beams which displayed section loss at the abutments.

After choosing the beams to rate, I calculated the dead loads and live load factors and then I calculated the equivalent plate geometry to account for beams with section losses. Since BRASS-GIRDER does not include a command for section loss the beams were modeled as plate girders with section properties that compare to the rolled beam.

I then moved onto setting up the BRASS-Girder input file, which were broken down into as built and as inspected for those with section loss.

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.

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.