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GTI Plastic Duct GTI GTI USA

GTI plastic post tensioning duct sets the standard and offers the highest level of corrosion protection available for specified PT systems PL 1 through PL 3 as defined in fib and PTI ASBI The duct is manufactured in a wide variety of diameters and custom lengths Multiple connection details are available in both slip on style or welded

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PDF ASSESSMENT OF GROUTS FOR POST TENSIONING

2021 10 05 nbsp 0183 32 Post tensioning is one of the most widely used technologies in many major infrastructure projects The tendons are the lifeline of Post Tensioned structures and grouts act as their last line of

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Development of a Standard Accelerated Corrosion Test for

Recent corrosion problems found in Florida s post tensioned bridges have shown how important quality grouting materials and proper grouting techniques can be to the longevity of State bridges Portland cement grout is commonly used to fill the voids in post tensioning ducts after the tendon is stressed Portland cement grout provides a protective barrier high alkaline

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RC 1632 Evaluating Pretressing Strands and Post

reinforcement and post tensioning ducts Laboratory specimens simulated debonding and voids around steel reinforcement loss of cross section area of steel reinforcement and various grouting challenges The NDE methods used were 1 ultrasonic testing for delamination void detection 2 electrochemical measurements for assessing the corrosive environment and 3

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Applications and Limitations of Impact Echo Scanning for

of the Impact Echo Scanning IES system for void detection in post tensioned bridge ducts The nominal thickness of the test panels ranged from 0 2 – 0 7 m with plastic and steel ducts inside The diameter of the ducts ranged from 50 to 120 mm One tapered section with wall thicknesses between 0 2

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NONDESTRUCTIVE DETECTION OF POST TENSIONING TENDONS

obtained during solar heating and silicone rubber flexible heating blanket tests Post tensioning ducts and simulated voids were detected in specimens up to 30 cm 12 in thick with a 75 176 C 135 176 F temperature gradient using an infrared heater The post tensioning ducts were detected

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NONDESTRUCTIVE DETECTION OF POST TENSIONING

Detection of simulated voids and post tensioning ducts with 5 cm 2 in of concrete cover in 20 cm 8 in thick specimens was possible with a temperature gradient of 11 1 176 C 20 176 F obtained during solar heating and silicone rubber flexible heating blanket tests Post tensioning ducts and simulated voids were detected in specimens up to 30 cm 12 in thick with a 75 176 C 135 176 F

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Non Destructive Testing Methods to Identify Voids in

Non Destructive Testing Methods to Identify Voids in External Post Tensioned Tendons Vol 16 No 3 March 2012 −389 − systems seldom show these surface distress indicators

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10 1016 j conbuildmat 2006 04 009 DeepDyve

2020 06 11 nbsp 0183 32 Concerning the frequency response on post tensioning ducts the following three relationships between the wavelength and the depth of duct are known 7 1 f T 0 96 C p 2 T 2 f s C p 4 d 3 f V 0 96 C p 2 d where f T is the resonance frequency of the plate of thickness T f S is the resonance frequency of a fully grouted steel duct at the depth d f V is

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Testing for Grouts for Post tensioning Ducts Mo Civil

Testing for Grouts for Post tensioning Ducts Tests shall be done for grout to verify the strength and properties of the grout laboratory tests shall be done on mix trials sufficiently prior to the beginning of grouting process to confirm the properties of the grout mix tests such as setting time compressive strength permeability volume change fluidity bleed and others

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Non Destructive Assessment And Remedy Of Grouted

the art and state of practice review on the available non destructive testing NDT techniques ii conduct laboratory testing on simulated bridge deck segments with grout encased prestressing cables to evaluate promising candidate method identified from the literature review that may be applicable to detect voids in the ducts cable fracture or corrosion in post tensioned decks

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Impact Echo Testing Services IE Measure Concrete Thickness

Fast acquiring IE testing 1000 points hour Best for high resolution imaging of large areas for internal concrete conditions Example applications slab thickness profiling and flaw detection pavement testing location of ungrouted sections of post tensioning ducts Read a paper on the IES as applied to PT duct void location

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NONDESTRUCTIVE TESTING METHODS TO DETECT VOIDS IN

2003 05 30 nbsp 0183 32 NONDESTRUCTIVE TESTING METHODS TO DETECT VOIDS IN BONDED POST TENSIONED DUCTS The use of post tensioning in bridges provides durability and structural benefits to the system while expediting the construction process However there is considerable interest to determine whether a tendon duct is properly filled with grout or not

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Impact Echo Scanning for Grout Void Detection in Post

Impact Echo Scanning for Grout Void Detection in Post tensioned Bridge Ducts Findings from a Research Project and a Case History presented at ASCE Structures Congress Long Beach California May 2007 Authors Yajai Tinkey Ph D Olson Engineering Inc 12401 W 49th Ave Wheat Ridge CO 80033 USA yajai olsonengineering com Larry D Olson P E Olson

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GROUTED POST TENSIONING TENDON EVALUATION

POST TENSIONING EVALUATION TECHNIQUES Post tensioning evaluation techniques vary from simple visual inspection to advanced ultrasonic impact echo void detection which can be used alone as well as in a combination to have a more complete evaluation Visual inspection The visual inspection focuses on identifying cracking

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Diagnosing Deficiencies in Post Tensioned Bridges

Visual inspection 10 post tensioned system PTS bridges utilizing New Directions for Florida PT Bridges Volume 9 Contract documents review Select bridges whose PTS were at a high risk of deficiencies Phase 2 Determine type of NDT and or IT of tendons and locations Perform NDT and IT of tendons using a statistical approach

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Testing Post Tensioning Ducts for Voids NDT Corporation

Testing Post Tensioning Ducts for Voids Grout voids in post tensioning ducts create the potential for corrosion and failure of tendons Sonic ultrasonic impact echo testing is used to locate grout voids Voids are verified with a small drill hole and tendon corrosion conditions documented with a bore scope video

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Detection of Voids Soft Grout and Tendon Corrosion NDT

NDT Corporation uses nondestructive testing methods to identify specific locations within internal post tensioning ducts where grout voids and soft grout exist Then verifies the nondestructive testing results by drilling a small hole to the duct opening the duct with tools designed for this task and verifying grout condition with probing and documenting tendon corrosion with video

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Grouting procedures for post tensioning system

2020 10 29 nbsp 0183 32 Grouting is very essential for post tensioned elements for the protection of high tensile steel elements as well as for better behavior at the ultimate stage of bonded cables Cement grout surrounding the steel element provides an alkaline environment which protects the steel from corrosion Hence it shall be ensured that grout is present in the entire duct without

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Impact Echo Scanning Evaluation of Grout Void Conditions

Post Tensioning Ducts for Tendon Corrosion Mitigation By Yajai Tinkey and Larry D Olson P ost tensioned PT systems have been widely used for bridge transportation systems since the late 1950s If a good quality control plan is not implemented however there is a strong possibility that during construction the ducts may not be fully grouted This results in voids in some

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Detecting Voids in Grouted Tendon Ducts of Post Tensioned

1996 07 01 nbsp 0183 32 Numerical and laboratory studies demonstrated that the impact echo method could be used successfully to detect both complete and partial voids in grouted tendon ducts Afield study was then conducted on an exist ing post tensioned bridge Fully grouted partially grouted and ungrouted tendon ducts located in actual bridge girders were examined The results of

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New York Post Tension LLC VIDEO GALLERY

Non Destructive Testing NDT and Evaluation of Post Tensioning Tendons with Voids The tendon paths of internal post tensioning tendons are determined using Ground Penetrating Radar devices This technique can be used successfully and is relatively fast in locating metal ducts and mild reinforcement embedded in concrete Plastic ducts can also be located by an

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Void Volumes GBG

Where voids are discovered or suspected in post tensioned ducts a simple pressure test using compressed air can be used to determine the approximate void volume The equipment consists of a pressure cylinder of known volume approximately 8 litres and an expanding plug to seal in the hole used to access the duct The pressure cylinder is pressurised to approximately 1000

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Non destructive testing methods to identify voids in

2012 02 29 nbsp 0183 32 However the sounding inspection method is not affected by the discontinuities and successfully identifies voids in test specimens Thus the sounding inspection can be an effective tool for identifying voids because of its easy application in the field A considerable number of Post Tensioned PT bridges have been constructed because PT systems enable them to

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EVALUATING NONDESTRUCTINE TESTING TECHNIQUES

to detect voids in bonded post tensioned ducts by elie george andary a thesis presented to the graduate school of the university of florida in partial fulfillment of the requirements for the

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Detection of Voids Soft Grout and Tendon Corrosion in

velocity testing in identifying open air and water filled grout voids and soft grout areas within post tensioning ducts The testing procedure is a three step process 1 Accurately locate and mark PT duct locations with ground penetrating radar GPR 2 Evaluate grout conditions in the duct with nondestructive sonic ultrasonic impact

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Newsletters NDT Corporation

Testing Post Tensioning Ducts for Voids Grout voids in post tensioning ducts create the potential for corrosion and failure of tendons Sonic ultrasonic impact echo testing is used to locate grout voids Voids are verified with a small drill hole and tendon corrosion conditions documented with a bore scope video

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GROUTING TESTS ON LARGE POST TENSIONING SECONDARY

GROUTING TESTS ON LARGE POST TENSIONING TENDONS FOR SECONDARY NUCLEAR CONTAINMENT STRUCTURES Tests of sedimentation bleeding and expansion of neat cement grouts were made as part of a program to insure successful grouting of large capacity long vertical post tensioning tendons and large capacity tendons on sharp curvatures Water

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PDF Non destructive testing methods to identify voids in

Based on literature review several Non Destructive Testing NDT methods are compared for effectiveness of identifying voids in external PT tendons and the

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Non Destructive Testing Methods to Identify Voids in

2015 10 29 nbsp 0183 32 Home Documents Non Destructive Testing Methods to Identify Voids in External Post Tensioned Tendons