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PRESTRESSED CONCRETE DESIGN EXAM 2025 | ALL
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A contractor pursuing approval for submittal items prior to construction ------ ---CORRECT ANSWER-----------------shop drawings and design drawings showing detailed engineering and installation The transition between the corrosion protection for the bond and free stressing lengths shall be designed to ensure ---------CORRECT ANSWER- ----------------continuous protection from corrosive attack The following responsibilities must be assigned before started a rock and soil anchor project,with the exception of ---------CORRECT ANSWER--------- --------a final punchlist for initiating the warranty of the system If grout is used to protect the outside of a steel trumpet, a minimum cover of __ is required ---------CORRECT ANSWER-----------------2 inches The use of UV- resistant coating bearing plates is ---------CORRECT ANSWER-----------------permitted as an alternate to a galvanized plate A coupler used in an anchorage system must be sealed to either the encapsulation or the tendon sheath using ---------CORRECT ANSWER------ -----------a heat shrink sleeve
The connection between the trumpet and the bearing plate must --------- CORRECT ANSWER-----------------be watertight The prestressing steel in the free length area is protected by --------- CORRECT ANSWER-----------------a corrosion- inhabiting comound,grout encasement,and the trumpet When encapsulation in not available under class I conditions, the contractor or installer ---------CORRECT ANSWER-----------------is permitted to use an epoxy- coated strand that has passed the appropriate water pressure test Type II Portland cement shall be used for grouting anchor system provided that ---------CORRECT ANSWER-----------------the sulfate content is between 0.1 and 0.2 percent Grout socks must conform to ---------CORRECT ANSWER----------------- ASTM D 4751 Plastic tubing wall thickness is acceptable for use in anchorage systems when ---------CORRECT ANSWER-----------------its normal thickness for PVC os .040 inches The test method for the melting point of wax ---------CORRECT ANSWER--- --------------is ASTM D- 566
admixture that will prevent the grout from flash setting when ambient temperatures rise above 100A and its unavoidable that the grout temperature would rise above 90A Fahrenheit When handling prestressing steel on site, care should be taken --------- CORRECT ANSWER-----------------not to expose the prestressing steel to a heat source above 450A Fahrenheit If the drilling subcontractor plans to dill and anchor hole at 3:00pm today for an anchor that will not be installed tomorrow morning at 7:00 am , the the subcontractor should ---------CORRECT ANSWER-----------------plan to re clean the hold prior to installing the tendon or the grout Drill holes designed to anchor a large soil excavation ---------CORRECT ANSWER-----------------must be drilled within a 12 inch diameter circle of its plan location First patent for Prestressed concrete from San Francisco, Callifornia in
- ---------CORRECT ANSWER-----------------P.H. Jackson Started modern development of prestressed concrete in 1928 --------- CORRECT ANSWER-----------------Freyssinet He introduced th explanation of prestressed concrete by means of a book. - --------CORRECT ANSWER-----------------Professor Magnel
Form of concrete in which internal stresses are introduced by means of high strength pre strained reinforcement ---------CORRECT ANSWER-------- ---------Prestressed Concrete Prestressed concrete Relies on _ and _ to achieve stress transfer to concrete ---------CORRECT ANSWER-----------------Bond and Bearing mechanism in prestressed concrete members ---------CORRECT ANSWER----------------- Steel is in Tension Concrete is in Compression Give atleast 3 reasons for prestressing: ---------CORRECT ANSWER--------- --------1. Eliminate cracking at service loading conditions.
- Improve shear and torsion strengths
- Add protection to the steel A Sufficient precompression to ensure "Cracked free" at full design load. By Freyssinet 1930 ---------CORRECT ANSWER-----------------Full prestressing Pre composition is not sufficient to prevent the cracks and it is commonly used. ---------CORRECT ANSWER-----------------Partial Prestressing Method of mechanical prestressing when concrete is cast around the prestressing tendon against external abutment. ---------CORRECT ANSWER-----------------Pre Tensioning
It is Useful in design and gives some idea to the eccentricity which can be given to the prestressing force once the cross section has been selected. -- -------CORRECT ANSWER-----------------Internal Couple It is assumed parabolic ---------CORRECT ANSWER----------------- Equivalents load concepts (load balancing) A negative sign that indicates the load is acting upward on concrete load balancing method of design. ---------CORRECT ANSWER----------------- Equivalents Loading Development of Prestressed Concrete in San Francisco by Lin in what year? ---------CORRECT ANSWER----------------- 1957 Difference between Prestressed and Reinforced Concrete --------- CORRECT ANSWER-----------------Prestressed concrete combines high strength concrete with high strength steel in " active manner" while Reinforced Concrete combines concrete and steel bars by simple putting them together and letting them act together as they may wish. combines high strength concrete with high strength steel in " active manner" ---------CORRECT ANSWER-----------------Prestressed Concrete combines concrete and steel bars by simple putting them together and letting them act together as they may wish. ---------CORRECT ANSWER---- -------------Reinforced Concrete
A brittle material with its tensile capacity now improve by being compressed. ---------CORRECT ANSWER-----------------Concrete A ductile and now made to act in high tension by prestressing. --------- CORRECT ANSWER-----------------Steel Intensional creation of permanent stresses in a structure or assembly. ------ ---CORRECT ANSWER-----------------Prestressing In ____ , Engineer of San Francisco, Callifornia named ____________ obtained patents for tightening steel tie rods in artificial stones and concrete arches to serve as floor slabs ---------CORRECT ANSWER----------------- 188 6, P.H Jackson In ____, C. E. __________ of Germany , Independent secured a patent for concrete reinforced with metal that had tensile stress applied to it before the slab was loaded. ---------CORRECT ANSWER-----------------1888, W. Doehring in ____, ________ of United Stated suggested possibility of retighting the reinforcing rods. ---------CORRECT ANSWER-----------------1908, C.R. Steiner in ____, ____________ of Nebraska tried high strength steel bars coated to prevent bond with concrete by means of NUTTS. ---------CORRECT ANSWER-----------------1925, R.E Dill
In what year did the 47% of all bridges built in Germany? ---------CORRECT ANSWER----------------- 1965 How many percent % of all bridges built in Germany? ---------CORRECT ANSWER-----------------47% In 1978, Soviet Russia annually produced ______ m3 of prestressed concrete ---------CORRECT ANSWER-----------------25 Million In ______, A famed construction of __________ begun ---------CORRECT ANSWER-----------------1949, Philiadelphia Walnut Lane Bridge When did the use of Prestressed concrete become a standard practice in United States? ---------CORRECT ANSWER----------------- 1960 In what year does post tensioned bridges of medium span have gained momentum in the form of continuous / cantilever construction? --------- CORRECT ANSWER-----------------Late 1970's in this year there was only one pre cast pre tensioning plant in US --------- CORRECT ANSWER----------------- 1950 PCI ---------CORRECT ANSWER-----------------Prestressed Concrete Institute
PTI ---------CORRECT ANSWER-----------------Post Tensioning Institute FIP ---------CORRECT ANSWER-----------------International Federation for Prestressing In ---- , Both precast, prestressed members and post tensioned, cast in place concrete are being utilized? ---------CORRECT ANSWER----------------
- 1970 When did PCI formed? ---------CORRECT ANSWER----------------- 1954 In ______, The introduction of PCI's " Prestressed Concrete Handbook" and also the acceptance of P.C as structural designers ---------CORRECT ANSWER----------------- 1971 Classification and types ---------CORRECT ANSWER-----------------1. Externally /Internally Prestressed
- Linear/Circular Prestressing 3.. Pretensioning & Posttentioning
- End- Anchored / Non-End- Anchord tendons
- Bonded/Unbonded tendon
- PreCast, Cast in Place, Composite construction
- Partial & Full prestressing It is where the arch was prestressed by jacking against its abutments. ------- --CORRECT ANSWER-----------------Externally or Internally Prestressed
The procedure of economical to pre cast part of a member , erect it, and then cast remaining portion in place ---------CORRECT ANSWER-------------- ---Composite construction The concrete is said to be ________ when a member is designed so that under the working load there are no tensile stress in it ---------CORRECT ANSWER-----------------Full Prestressing If some tensile stress will be produced in the member under working load -- -------CORRECT ANSWER-----------------Partial Prestressing What are the stages of loading ---------CORRECT ANSWER-----------------1. Initial Stage
- Intermediate Stage
- Final Stage It is not subjected to any superimposed external loads ---------CORRECT ANSWER-----------------Initial Stage The stage during transportation and erection ---------CORRECT ANSWER-- ---------------Intermediate Stage When Actual working loads come on the structure. ---------CORRECT ANSWER-----------------Final Stage
What are the types of load in Final Stage: ---------CORRECT ANSWER------ -----------1. sustained load
- working load
- cracking load
- ultimate load It permits better control in mass production and often economical. --------- CORRECT ANSWER-----------------Precasting form of concrete in which internal stresses are introduced by means of high strength pre strained reinforcement ---------CORRECT ANSWER-------------- ---Prestressed Concrete Prestressed relies on _______ or __________ to achieve stress transfer to concrete. ---------CORRECT ANSWER-----------------bond or bearing mechanism Induce internal actionsof such magnitude distribution to counter actthe external loading ---------CORRECT ANSWER-----------------Prestressing Forces It combines concrete and steel bars ---------CORRECT ANSWER-------------- ---Reinforced Concrete combines high strength with high strength steel in an "active manner" ------- --CORRECT ANSWER-----------------Prestressed Concrete
In a unbonded system, the force applied to the concrete after tensioning ---- -----CORRECT ANSWER-----------------comes from the anchorage zone only Post-tension manufacturing plants must be certified by ---------CORRECT ANSWER-----------------PTI unbonded plant certification program Prior to cutting the tendon tails after tensioning,the field records of stressing activities must be forwarded to and approved by ---------CORRECT ANSWER-----------------the engineer of record In the event that a new set of stressing equipment is delivered to project,the equipment should contain___ for review prior to being used on- site ---------CORRECT ANSWER-----------------a current calibration chart relating gauge pressure to force applied According to the field procedures manual for unbonded single strand tendons,all of the following items are necessary for post- tension document control except ---------CORRECT ANSWER-----------------concrete strength results When reporting stressing results,the following information is necessary to record ---------CORRECT ANSWER-----------------Jack and gauge serial # & elongation measurements and percentage deviation When moving post-tension cables across the site, the use of __ is permitted ---------CORRECT ANSWER-----------------Nylon slings,with unloading as close to the intended placement as possible
When storing post-tension cables,care must be taken to ---------CORRECT ANSWER-----------------prevent the cables from being exposed to weather elements and moisture during delivery, it is the ___ responsibility to ensure the delivered items match the shipping list ---------CORRECT ANSWER-----------------buyers On a two-way flat plate,a minimum of __ over each column first --------- CORRECT ANSWER-----------------2 uniform tendons should be placed A minimum of _- of tendon tail must be available at the stressing end. ------- --CORRECT ANSWER----------------- 12 inches When installing a post-tension system,the installer should have a minimum of ---------CORRECT ANSWER-----------------5 years experience, be a PTI certified installer, and use the same crew that installs the system to stress the system The layout and installation of post- tension cables ---------CORRECT ANSWER-----------------takes precedence over the placement of electrical and mechanical conduit & other necessary reinforcing steel
--verify that the contractor has stressed the fixed-end anchorages to ensure wedges have been seated The jacking force specified for 1/2- inch diameter tendons is normally --------
- CORRECT ANSWER-----------------33 kips The inspection of a post- tension system is the responsibility of --------- CORRECT ANSWER-----------------The engineer of record ,the special inspector , the general contractor, and a PTI certified installer Temperature tendon profiles will ---------CORRECT ANSWER----------------- remain at a constant height throughout the slab The edge form should be marked showing the center of each post tension tendon from ---------CORRECT ANSWER-----------------The approved installation drawings All of the following can affect tendon elongation field measurements except ---------CORRECT ANSWER-----------------the jack extends or retracts slowly Prior to stressing tendons, the inspector should check that --------- CORRECT ANSWER-----------------the tendon is perpendicular to the anchor & the amchor is parallel to the face of the concrete, unless the plans specify a different angle
During stressing operations,the special inspector ---------CORRECT ANSWER-----------------should measure the tendon elongations after each cable is stressed The last calibration date of the stressing equipment must ---------CORRECT ANSWER-----------------not exceed 6 months from the stressing date Cleaning the tendon tails prior to stressing improves ---------CORRECT ANSWER-----------------The consistency and permanence of the paint mark & the efforts to keep the underside of the jack clean Tensioning cables should not begin until ---------CORRECT ANSWER-------- ---------concrete cylinder breaks show that member has attained the minimum compressive strength specified for stressing on the project plans When preparing for stressing, it is necessary to ---------CORRECT ANSWER-----------------Check to make sure the stressing equipment is clean, especially the jack gripper and seating plunger areas,remove PT coating from the tendon and clean out the anchor cavity, and seat the wedges with use of hand seating tool __ is an acceptable field measured elongation of a tendon with a theoretical delta of 6-3/4" ---------CORRECT ANSWER----------------- 6 - 3/ When recording post- tension stressing results, the inspector should note -- -------CORRECT ANSWER-----------------The serial number of the jack and gauge, weather conditions, the name of the general contractor and the name of the equipment operator
