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demolition of posttensioned concrete

demolition of posttensioned concrete

Demolition of post-tensioned concrete

Demolition of post-tensioned concrete Safe release of stored energy requires a reverse sequence of the original construction procedures The crack in this C segment extended in length and width after the string course was complete. The crack follows the position of the

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Demolition of Post-Tensioned Concrete Concrete ...

1976-6-1  Little has been published about the demolition of post-tensioned concrete but there is enough such concrete now in service to become a problem for demolition contractors. When a demolition sequence is being planned it is important to have a knowledge of the erection procedure and a set of the as-built record drawings.

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DEMOLITION OF POST-TENSIONED CONCRETE

DEMOLITION OF POST-TENSIONED CONCRETE. The author discusses the problem of the demolition of post-tensioned concrete, using as an example the demolition of nine prestressed concrete beams and the repair of others during the construction of bridges on the M3 motorway. In this example during prestressing operations on the first three of ten 3 ...

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Safe demolition of post-tensioned reinforced concrete ...

2018-9-24  Lack of as-built records and published papers can make safe demolition of post-tensioned structures difficult. John Riddle of Topbond explains how reverse-engineering techniques can be used to design the temporary bracing needed to contain post-tensioning forces during demolition.

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Safe demolition of post-tensioned reinforced concrete ...

2018-9-24  Lack of as-built records and published papers can make safe demolition of post-tensioned structures difficult. John Riddle of Topbond explains how reverse-engineering techniques can be used to design the temporary bracing needed to contain post-tensioning forces during demolition.

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Demolishing a Post-Tensioned Parking Garage

1991-10-1  Describes the demolition by headache ball of a post-tensioned concrete parking structure. Detensioning the tendons was found to be neither necessary nor desirable, since the ties provided by the tendons were an advantageous live force that could be controlled. Beam-column and anchor performance is

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PTI DC80.1 - Controlled Demolition of an Unbonded Post ...

2002-1-1  The purpose of this report is to document a specific controlled demolition procedure of an unbonded post-tensioned concrete slab, which was executed successfully on a large project. During the demolition process the response of the tendons being neutralized was monitored and documented. The observations made arc categorized and presented.

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CONTROLLED DEMOLITION OF A POST-TENSIONED BEAM

CONTROLLED DEMOLITION OF A POST-TENSIONED BEAM A controlled demolition process of a post tensioned beam, 810 mm thick and 685 mm wide, is described. The beam was designed to carry a uniform dead load of 146 kn/m and two point loads of 164

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Post-Tensioned building demolition - Demolition ...

2016-7-17  Canuck65 (Structural) 17 Jul 16 15:52. Ampersand, I was involved in the rehabilitation of a large, unbonded, post-tensioned parking structure where the slab tendons were de-stressed, removed and replaced. I personally witnessed the de-stressing of upwards of a thousand tendons. Keep in mind, every situation/structure is different.

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Demolition of Post-Tensioned Concrete Prestressed ...

2019-1-3  Demolition of. post-tensioned concrete Safe release of stored energy requires a reverse sequence of the original construction procedures. ittle has been published. L about the demolition of post-tensioned concrete but there is enough such concrete now in service to become a problem for demolition contractors. When a demolition sequence is being planned it is important to have a knowledge of ...

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Safe demolition of post-tensioned reinforced concrete ...

2018-9-24  Lack of as-built records and published papers can make safe demolition of post-tensioned structures difficult. John Riddle of Topbond explains how reverse-engineering techniques can be used to design the temporary bracing needed to contain post-tensioning forces during demolition.

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Demolition of Bonded Post-Tensioned Floor System

2021-1-28  Demolition of bonded post-tensioned floor system, when the strands break, they will not immediately shrink due to the abundance of grout in the galvanized duct causing bond force between strands and concrete. This is considered an advantage of the system. Tendon placement in post-tensioned floor mostly employs band-distribute layout as

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364.8T-02(11) Use of Hydrodemolition for Concrete

2017-8-5  of the appropriate method of concrete removal is crucial. Hydrodemolition is not recommended for concrete removal if there is a possibility that unbonded post-tensioned systems are within the concrete removal zone. References 1. Sprinkel, M. M., “Preparing Bridge Decks for Overlays,” Concrete Repair Digest, V. 8, No. 5, 1997, pp. 242-247. 2.

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Post-Tensioned building demolition - Demolition ...

2016-7-17  Canuck65 (Structural) 17 Jul 16 15:52. Ampersand, I was involved in the rehabilitation of a large, unbonded, post-tensioned parking structure where the slab tendons were de-stressed, removed and replaced. I personally witnessed the de-stressing of upwards of a thousand tendons. Keep in mind, every situation/structure is different.

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STRUCTURE magazine Post-Tensioned Concrete Construction

Once the de-tensioning and demolition are complete, the profile of the tendons can also be adjusted within the work area to address the new structural spans and geometry. Once the tendon work is finished, including the addition of new end anchorages, the concrete floor slab is recast with rebar reinforcement (Figure 3). Bonding agents help ...

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Post-Tensioned Bridge Assessment Assessment Demolition ...

2015-7-7  Parametric study of the residual strength of deteriorating simply-supported post-tensioned concrete bridges Authors: D. G. Cavell , P. Waldron Source: Proceedings of the Institution of Civil Engineers - Structures and Buildings, Volume 146, Issue 4 , 1 Nov 2001 (341–352)

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CONTRARY TO POPULAR OPINION, POST-TENSIONED SLABS

2005-9-1  Another considerable cost advantage is the fact that concrete construction can provide more floors within a given height restriction, particularly through the use of posttensioned suspended concrete floors. These can be some 300mm thinner than alternative methods of construction.

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Assessment of Stresses in Post-Tensioned Concrete Bridges ...

This paper presents the results of trials carried out on a post-tensioned concrete six-cell box structure to determine the in-situ stress levels. The techniques used were based on the stress-relief which occurs during the removal of concrete cores and the re-establishment of

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CSDA Contractor Scans for Post ... - Concrete Openings

Using a Hilti PS 1000, Semidey scanned the concrete to locate the post-tension cables in order to see how deep they were embedded in the concrete slab. Once he was sure of the depth, he marked the Husqvarna Quick Cutsaw blade that was being used to cut a small trench for the electrical line.

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Demolition of Post-Tensioned Concrete Prestressed ...

2019-1-3  Demolition of. post-tensioned concrete Safe release of stored energy requires a reverse sequence of the original construction procedures. ittle has been published. L about the demolition of post-tensioned concrete but there is enough such concrete now in service to become a problem for demolition contractors. When a demolition sequence is being planned it is important to have a knowledge of ...

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Post-Tensioned building demolition - Demolition ...

2016-7-17  I am beginning to prepare a structural demolition plan and shoring plan for a multi-story post-tensioned structure. I have assessed the equipment the contractor will be operating on the decks, and I have designed the shoring required under the working surface before demolition of a floor may begin.

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Logan International Airport, West Parking, Controlled ...

2021-7-5  A portion of the West Parking Garage fifth floor was cast on a snowy day. When the forms were stripped, contractor observed cracks and ice-filled voids in the slab. The owner and contractor needed to know if the 20,000 sq ft deck could be repaired or

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Post-Tensioned Bridge Assessment Assessment Demolition ...

2015-7-7  Parametric study of the residual strength of deteriorating simply-supported post-tensioned concrete bridges Authors: D. G. Cavell , P. Waldron Source: Proceedings of the Institution of Civil Engineers - Structures and Buildings, Volume 146, Issue 4 , 1 Nov 2001 (341–352)

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Contemporary Post-tensioned Concrete Construction ...

Controlled demolition of an unbonded post-tensioned concrete slab (PTI special report). Post-Tensioning Institute, Pheonix AZ, 34 pp. Google Scholar Bletzacker, R. W. (1967).

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Chapter 1 - Introduction Bridge Demolition Practices ...

Advances in design and construction such as prestressed and posttensioned concrete, longer spans and high strength materials, increased use of continuous spans, curved girder, box girder, and cable-stayed bridges yield structures where demolition

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Controlled Demolition of Prestressed Concrete Handout.pdf ...

View Notes - Controlled Demolition of Prestressed Concrete Handout.pdf from CIVE 510 at Drexel University. cfw_1qu 510 /CNE 5540 Taking down an unbonded post-tensioned concrete

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ViewpoinT Creating Openings in UnbOnded pOst

2018-4-4  20 ConCrete repair Bulletin May/june 2013 icri Creating Openings in UnbOnded pOst-tensiOned slabs By Don Kline i t is often necessary to create openings in existing concrete slabs. Openings may be large, such as those required for a new stairway, or small core penetrations, such as those required for plumbing risers.

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Comparison of NDT techniques on a post-tensioned beam ...

Following the complete demolition of a prestressed concrete bridge in southern France, a suspected weak post-tensioned beam was retained for non-destructive testing (NDT). Ground penetrating radar, Ferroscan ® (covermeter), gamma-ray radiography and impact-echo methods have all been tested and their results then discussed after the autopsy of ...

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CASE STUDY: INVESTIGATING THE FAILURE OF KHANI

Babeldaob Bridge. They both had post-tensioned single cell concrete box girder non-prismatic sections. Koror-Babeldaob Bridge was a balanced cantilever prestressed concrete box girder bridge with a main span of 240.8 meters and a total length of 385.6 meters built in the Republic of Palau in 1978 by Socio Construction Company [6]. Figure 4.

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