ASPIRE Fall 2012 - Aspire - The Concrete Bridge Magazine

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created with vertical post-tensioning. This connection transferred the unbalanced moment during placement of the drop-in girder spans on the pier cap. Strongbacks were designed to support the girder loads. Concrete pumping trucks were used in series to install the self-consolidating concrete in the drilled shafts. MSE retaining wall and articulated concrete block mattresses were used as an access road. The new bridge abutments, wingwalls, and MSE walls were all subject to scour and required deep foundations. The abutments and wingwalls were installed on prestressed concrete piles, and the MSE walls were constructed on controlled modulus columns. A controlled modulus column (CMC) is a soil improvement method used to stabilize an area of typically poor soil. An auger forcibly displaces soil and grouts a column of concrete into the ground. The Mullica River Bridge has 2129 CMCs on the project. Additionally, articulated concrete block mattresses were installed to provide scour protection for the existing bridge. Superstructure Concrete was selected as the material of choice for the new superstructure to eliminate future painting costs associated with steel bridge sustainment in this coastal area. The new bridge is a 1230-ft-long continuous, spliced, post-tensioned concrete girder bridge with four main spans of 220 ft and two end spans of 175 ft. It is currently one of the longest, continuous, post-tensioned spliced girder units in North America. Modular deck joints are provided only at the abutments. The seven lines of AASHTO Type VI Modified post-tensioned concrete composite girders were spaced at 8 ft 6 in. on centers. The Type VI girders are haunched over the piers and support dropin segments. The girder depth varies from 78 in. deep at midspan to 108 in. deep at the piers with each pier segment weighing 137,500 lb. Specified concrete compressive strength for the beams was 8 ksi. The sequence of girder erection consisted of: • erecting pier segments at five piers, • installing drop-in segments in the four main spans, • installing drop-in segments in the two end spans, and • casting closure joints. Pretensioning was provided in each of the segments to account for anticipated shipping, handling, and erection stresses. Corrugated plastic ducts were embedded in the beam for the post-tensioning tendons. The design specified four tendons each consisting of twelve, 0.6-in.-diameter, seven-wire strands. Two tendons were tensioned after the girders were erected to achieve continuity. The remaining two tendons were tensioned after the concrete deck slab was placed and cured. Temporary moment connections between the haunched girders and the pier cap were The high-performance concrete (HPC) deck construction for the Mullica River Bridge went smoothly from start to finish. The specifications detailed important requirements such as a 14-day wet cure burlap application along with Rainhart Profilograph ride quality testing. Two-stage post-tensioning provided residual compression in the deck due to the tensioning of two of the four girder tendons after the composite deck had been placed. A time-step analysis model was used to evaluate the loading during the girder erection and the post-tensioning phases. Careful consideration and evaluation for temporary unbalanced load conditions on the permanent structure, vertical and horizontal deflections, and loads of both the girders and piers were conducted as each component was constructed. The benefit of this methodology was the elimination of the typical shored construction method using temporary support towers for the superstructure (prior to splicing), resulting in considerable construction cost savings. Summary This project presented significant environmental challenges and considerations, restrictive construction windows, unique seismic design applications, and is currently on pace to open, with traffic flowing in both directions and over both structures, by December 2013. __________ Tom Fisher is the project manager, Dave Rue is the structural lead, and Judson Wible is a structural engineer, all at Parsons Brinkerhoff Inc., Lawrenceville, N.J. Elizabeth Trimpin is a project manager, New Jersey Turnpike Authority, Woodbridge, N.J. For additional photographs or information on this or other projects, visit www.aspirebridge.org and open Current Issue. 24 | ASPIRE, Fall 2012
1104_Helser_usa:Layout 1 21.06.2011 16:40 Uhr Seite 1 When it comes to your next project … Helser Industries has a one track mind ! For over 50 years Helser has engineered and manufactured precise custom steel forms to meet the unique requirements of their customers. Helser’s expertise was utilized in the construction of the Las Vegas monorail. The success of this high profile project was instrumental in Helser forms being specified for the monorail system currently under construction in Sao Paulo Brazil. Whether your project requires precise architectural detail, structural elements or transportation application, 1-503-692-6909 Helser Industries is on track to get it done right and get it done on time! www.helser.com ASPIRE, Fall 2012 | 25
Page 1 and 2: THE CONCRETE BRIDGE MAGAZINE FALL 2
Page 3 and 4: Photo: Alfred Benesch and Company.
Page 5 and 6: ASPIRE, Spring 2012 | 3
Page 7 and 8: DESIGN CONSTRUCTION ANALYSIS ASPIRE
Page 9 and 10: see the Summer 2012 issue of ASPIRE
Page 11 and 12: to accurately create the concrete e
Page 13 and 14: fib Approach The Model Code for Ser
Page 15 and 16: Precast concrete spliced U-girders
Page 17 and 18: 3½” 3’-7” 3’-7” 5” 2½
Page 19 and 20: Epoxy-Coated reinforcing Type 205 S
Page 21 and 22: the up-station and down-station dec
Page 23 and 24: eight deck segments of the viaduct
Page 25: earth (MSE) walls to minimize the e
Page 29 and 30: After the concrete ribbon arch desi
Page 31 and 32: New Grouting Specification This spe
Page 33 and 34: Typical cross section, cast-in-plac
Page 35 and 36: AESTHETICS COMMENTARY by Frederick
Page 37 and 38: Looking north at the completed Blac
Page 39 and 40: ASPIRE, Fall 2012 | 37
Page 41 and 42: Precast segments were cast using th
Page 43 and 44: CREATE. ENHANCE. SUSTAIN. Second Pe
Page 45 and 46: Segmental Concrete Solutions by Cra
Page 47 and 48: The 120 segments in the main span o
Page 49 and 50: on detecting ASR in the field, conf
Page 51 and 52: Figure 5. Fifth Street Bridge over
Page 53 and 54: 2013 Call for Papers Abstracts due
Page 55 and 56: FREE On-Site Shotcrete Informationa
Page 57 and 58: Complete Solutions and Support for
Page 59 and 60: ASPIRE, Fall 2012 | 57
Page 61: www.holcim.us www.larsa4d.com www.m

ASPIRE Fall 2012 - Aspire - The Concrete Bridge Magazine

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