NUASCE

Peter Finch, project director from Amtrak gave a great technical presentation on the work done for the replacement of the vertical lift span of the Thames River Bridge located in Groton and New London, CT.  This bridge has a lot of traffic with about 38 trains per day and over 1600 annual openings, including opening for the United States Navy and Coastguard.

Some of the major design elements for this project were replacing the bascule, modifying the channel piers and constructing two 135 foot lift towers for a span of 188 feet, while retaining the approach spans and finding an efficient way to remove the old counterweights.

A major problem faced during this project was the settling of one of the piers after construction.  This became most important when the settlement did not appear to be stopping.  The settlement caused sinking and tilting of the pier which prohibited the opening of the bridge.  This problem was eventually solved through permeation grouting which filled the voids that had been causing settlement underneath the pier.

Though there were unforeseen challenges in the replacement of this lift span, the problems were solved effectively.  With a goal of July 4th, the bridge was complete for limited scheduled openings by July 1st and the approach spans are ready for painting in the near future.

This week, COE distinguished professor, PhD., P.E., and fellow ASCE member Mishac K. Yegian gave an enthusiastic presentation on the research he did for the Museum of Fine Arts in Boston involving the preservation of precious artifacts from the damaging effects of earthquakes.  The museum gets paid to lend the age old artifacts to other museums for viewing; however there was great apprehension in lending four particular sculptures to the Nagoya Museum in Japan due to the high seismic activity in that area.

Extensive research was done through the collaboration of Northeastern and the Museum of Fine Arts to evaluate the reduction of these seismic effects on the statues when placed on mechanical isolators.  When an object is placed on a mechanical isolator, the bottom plate of the mechanical isolator moves with the ground during an earthquake while the top plate, on which the object rests, undergoes far less disturbance.  This is occurs because the plates are separated by a geo-synthetic material that permits the plates to slide independently, allowing friction to absorb the earthquake and the energy to be isolated before it reaches the sculpture.

Models of the statues were made to conduct the research needed to find out if the mechanical isolators would actually be sufficient the aide against the seismic disturbances associated with the area.  The models were tested on a shaking table that simulated the museum floor during Kobe and Taft earthquakes.  The project was ultimately successful and the statues were able to be shipped and displayed in the Nagoya Museum in Japan.

Evan Souliere
Great Coasters
1 April 2009

Number of Students: 43
Number of Advisers: 2
Number of Faculty: 2

This week senior Evan Souliere gave a presentation of his work on roller coasters from his co-op at the company Great Coasters. Great Coasters is a company of about 10 employees that does design and construction of custom wooden roller coasters and repair of existing wooden coasters. They were featured on the discovery channel show “Build it Bigger” for one of their custom coasters. At this point, they have done 11 operating roller coasters. The interesting thing about the custom roller coasters is that they are designed to use the surrounding terrain and elements of the environment with many direction changes. For example, one coaster called “Thunderhead” was built into a large hillside with several turns that reversed direction.

The trains used for the coasters differ from the conventional standard due to the fact that each car is trailered to the car in front. This design prevents wear and tear on the wheels and the track, reducing maintenance costs for the park because standard re-tracking is not needed. The anatomy of a coaster design follows an analysis of 2-D truss structures with batters off the side for loading and interior chords. The steel track rests on top of a sequence of these trusses.

The coaster design process begins with the park/client accepting the rendering of a concept. A final design includes a plan view and a 2-D profile view. An energy line is important to the design, as it is the limiting factor for the coaster train to return back to the station safely. This line varies depending on temperature conditions. Construction of a coaster involves permits, land clearing and foundation surveying. Bent drawings are done for each and every single bent before construction. Once tracking and trains are installed, testing is done as a safety precaution. Although restraints are always used, the coasters are designed so that restraints are not necessary and people will not fly out from their seats. Great coasters is in the process of constructing 3 new coasters around the world. One coaster, Toro, is undergoing bent construction, while another, Prowler, is in the land clearing/foundation construction process. The final coaster is for the Terminator movie and is still undergoing design.

Peter Quigley
25 March 2009

Number of Students: 41
Number of Advisers: 1
Number of Faculty: 0

For this week’s lecture, Peter Quigley gave a talk on the new construction going on at the Museum of Fine arts in Boston. The existing site has undergone several additions over time since 1909. With the demolition of the existing mechanical plant and restaurant, the new addition will include a courtyard, gallery, and large pavilions.

Initially, construction began with shearwall installation and demolition. Pre-excavation was needed with soil mix walls to prevent any damage to remaining wings of the museum. The new courtyard will use an interesting facade system with non-linear cables. Normal systems can use a beam, a cable and strut, or cables with a removed strut. The designers of the courtyard were looking for a system that would be most transparent to allow for a clear view to the outside gardens. A cable analysis proved that linear cables would be unstable under wind conditions. However, conditions proved to be stable with non-linear cables, so a transparent system could be utilized. An interesting column model was also used inside the courtyard, with a composite steel section infilled with concrete, over a reinforced concrete column for fire protection. This gives the building 2 hour fire protection, which is unique for this type of structure. Overall, the addition will bring 165,000 square feet of new space with an increased live load capacity. The project is expected to be complete in the coming years, with a grand opening in late 2010.

Number of Students: 56
Number of Advisers: 2
Number of Faculty: 3

This week’s lecture featured Robert Nagi from VHB on the development of wind farms. Wind farms can be land based, shore based, or ocean based. The most efficient locations are offshore in the ocean, because of the constant availability of powerful wind gusts. Civil engineers play a large role in wind farm development. The process requires wind assessment, design, environmental studies, land acquistiion and permitting, manufacturing and construction, and transportation. There is a growing need to test wind blades for characteristics including bending and vibration. Construction and manufacture of the blades usually happens far away from testing facilities, so transportation is a very important issue.

Since wind blades can be huge, around 30 to 40 m in length, transportation can become a difficult procedure, especially through dense areas. There are many factors that need to be taken into account, such as the turning radius of the truck carrying the wind blade. Operators must watch for obstacles in the path of the container in 3 dimensions, including signs above, dips in the roadway, overhead bridges, etc. One example of a VHB job is at the Charlestown site in Massachusetts, which is very close to the ocean. The challenge with this site is that it is necessary to travel through neighborhoods on city streets. A solution to this challenge is the use of a special expandable truck with steerable back wheels, which helps to negotiate turns that would be impossible with a normal static truck. The use of new technology is helping to improve wind blade transport for the future.

For this week’s lecture, Mauro Scali from Simpson, Gumpertz, and Heger spoke about the process and applications of concrete petrography.   Concrete petrography is the study of hardened concrete micro-structure using microscopic techniques.  This study can help with the understanding of concrete conditions that lead to the failure of structures.  Mauro explained that the answers to questions on how and why a structure collapsed can be found by knowing exactly where to look.  It is important to not only understand the problems in the concrete, but also how to repair the issues.

The process begins with an important visual examination of the concrete.  Fractured aggregate and inadequate bonds in the concrete can be discovered just by looking at a photo of a structure.  Photographs of existing conditions are vital because they can show factors in the surrounding environment affecting concrete.  Next a cross cut section sample can also reveal more imperfections in the concrete.  Finally, microscopic examinations of ground down samples will show important information such as the degree of cementation or the water/cement ratio.   There are numerous causes for specific issues in concrete.  Cracking caused by drying shrinkage, corrosion, and freeze/thaw cycles or an improper water/cement ratio will add to structural failures.  One way to counteract cracking is with air entrainment.  Very small air voids added to concrete act as buffers that relieve expansive stress due to freezing, etc.   Concrete petrography is key in determining how a structure will fail.

Special thanks to Abe Finkelstein, our Secretary, for the write up.

Hey Everyone,

Here is this week’s update for ASCE:

Elections:
This Wednesday at 11:45am in 108 Snell Engineering, elections will be held for next year’s ASCE officers. If you would like to nominate someone, please email Rachael at meehan.r@neu.edu The following is a description of each position:

President : Makes sure everything runs smoothly.
Vice Presidents (2) : compiles annual report. Helps out the president.
Program Coordinators (2) : Sets up lecture series. This includes contacting and confirming pizzas, reserving rooms, ordering pizza, and any other necessary items for the meeting.
Treasurer : Handles money.
Publicity Coordinator : Makes posters for the meetings each week.
Secretary : Writes summary of each lecture.
Webmaster : updates the website (extensive web knowledge not necessary)

*There are currently no candidates for secretary so far.

Bocce:
Please play your next round by this Wednesday, April 8th.

Steel Bridge:
The steel bridge team would like to thank everyone who came out to support them at the competition this weekend.

SENIORS:
The brick ceremony will be held next Wednesday, April 15 at 11:45 am in 108 Snell Engineering. See you there!!

Thank you everyone for a great semester.

Kaitlin McCarthy
NUASCE President
Mccarthy.ka@neu.edu

Hey Everyone,

Here is this week’s update for ASCE:

Lecture Series:
This Wednesday, our very own Evan Souliere will be speaking about roller coaster design. In particular, he will be focusing on 3 wooden roller coasters that are opening this year that he helped to design. The meeting will be at 11:45 am in 108 Snell Engineering.

Bocce:
Due to inclement weather, I have pushed the deadline for first round games to Wednesday. However, most second round games do not depend on the outcome of the first round since both teams have bys. If this is the case, please try to play your game this week.

Officer Elections:
Officer elections will be held on Wednesday, April 8th instead of a lecture. If you are interested in running, please have a friend nominate you at this week’s meeting. The following is a description of each position:

President: Makes sure everything runs smoothly.

Vice Presidents (2): Compiles annual report.  Helps out the president.

Program Coordinators (2): Sets up lecture series. This includes contacting and confirming pizzas, reserving rooms, ordering pizza, and any other necessary items for the meeting.

Treasurer: Handles money.

Publicity Coordinator: Makes posters for the meetings each week.

Secretary: Writes summary of each lecture.

Webmaster: Updates the website (extensive web knowledge not necessary)

*There is currently no one running for secretary or webmaster and these are both great positions for first time officers. Please note that these elections are for next Spring. Therefore, you must be in the division that co-ops from July-December. Please email me with any questions.

Steel Bridge:
The competition is this Saturday at Wentworth! Feel free to stop by and cheer on our team. See schedule below:

7:00 AM Setting up of all school bridges for Aesthetic Judging
8:00 AM Aesthetic Judging begins
9:30 AM Construction and Loading of Bridges
12:30 - 2:00 PM Lunch Available, ongoing during Construction and loading

Contact Matt Kelly at Kelly.mat@neu.edu for more information.

See you Wednesday.

Kaitlin McCarthy
NUASCE President
mccarthy.ka@neu.edu

Hey Everyone,

Here is this week’s update for ASCE:

Lecture Series:
This Wednesday, Peter Quigley from Weidlinger Associates will be speaking about the structural aspects of the Museum of Fine Arts addition currently under construction. The meeting will be at 11:45 am in 108 Snell Engineering.

Bocce:
The official bocce bracket is up outside of Professor Tillman’s office. Please play first rounds by this FRIDAY! There are still spaces available to sign up if you would like to play.

SENIORS:
The date for the brick ceremony has been set! The ceremony will be Wednesday, April 15th (Reading Day) at 11:45 am in 108 Snell Engineering Center.

If you have any questions, please feel free to contact me.
See you Wednesday.

Kaitlin McCarthy
NUASCE President
mccarthy.ka@neu.edu

Pat Barb S&F Concrete
25 February 2009

Number of Students: 41
Number of Advisers: 1

This week’s lecture featured Pat Barb from S&F concrete.  Pat spoke about the different aspects of concrete construction projects, specifically the Clarendon condominium project in Boston, MA.  This project involved both conventional construction and up-down construction methods.  Up-down construction allows for the development of the building’s superstructure while excavation below grade is still in progress.  For the first time, cast-in-place concrete was used in an up-down construction project.  In order to carry out this process, it was necessary to determine how to transfer temporary loads from the superstructure to prevent a collapse on unfinished supports.  This was accomplished with the use of bearing plates at the top of load bearing elements and continuous reinforcing for columns and shear walls.  Construction began with the pouring of a deep foundation, followed by the slurry wall and caisson installation.  Water underneath the excavation holes caused problems with the curing concrete, so the slurry wall needed to be deep enough to counteract this.

Pat also spoke about the different considerations when choosing form work systems on a construction project.  These considerations included safety and intended use for desired quality, schedule and available equipment, and labor/productivity costs.  Usually, jump systems or rail climbing systems are used.  However, new perimeter protection systems can be used to improve safety, efficiency, and overall construction progress.  These systems involve attaching plywood around construction areas to provide a safe enclosure for workers and for the public below, minimizing fall exposure and falling debris.

Special thanks to Abe Finkelstein, our Secretary, for the write up.