JPH02161010A - Edge stracture of precast concrete pile using prestressed coupler nut - Google Patents

Abstract

PURPOSE:To obtain a pile with a simple edge structure by interlocking a coupler nut having screws in and out of one end thereof and having an interlocking projection to the other end with the head of a PC steel bar, and using it as a bolt hole for connecting ends after introducing prestress. CONSTITUTION:A coupler nut 1 having a female screw to screw with a bolt 7, a male screw to screw with an end plate 10 and a conical interlocking projection is interlocked with the head 9 of a PC steel bar 8. Then, a jack introducing prestress is fixed with a fixing bolt 12, and prestress is introduced. After that, the bolt 12 is removed to use it as a fixing screw for a end connection bolt 7, and it is used both as the PC steel bar and connection bolt. According to the constitution, a prestressed concrete pipe with a simple edge structure can be obtained.

Description

[Detailed description of the invention] 3-1. Industrial Field The present invention aims to obtain a highly earthquake-resistant pile cap structure in prestressed concrete pile foundation structures for architecture and civil engineering, and to efficiently introduce prestress into PC steel bars and connect the superstructure. A prestressed coupler nut that has the dual functions of fixing a PC steel bar and connecting a male thread to form a connection mechanism that transmits prestress to reinforcing bars, and a new prestressed concrete pile end structure using this prestressed coupler nut. Regarding.

3-2. Prior art prestressed concrete piles are a type of pile that combines high-strength concrete and high-tensile PC steel bars, and generates large bending strength by applying prestress by tensioning the PC steel bars. In the foundation construction method using this type of pile, a high-strength, high-quality antibody section is formed by factory manufacturing, but on the other hand, in terms of earthquake resistance of the headland joint, the headland structure is not manufactured with connection with the foundation slab in mind. At present, sufficient measures have not been taken in terms of structural construction. Up to now, a method of embedding a female coupler in the pile head to form an anchoring hole for superstructure connection reinforcing bars has been proposed as a pile cap processing method to obtain a pile cap joint with high earthquake resistance. However, the application to the end structure of piles has not been implemented due to manufacturing difficulties, and the situation has not been improved.

The standard end structure of this pile consists of a PC steel bar 8 and a joint end plate 10, as shown in Figures 1 and 2, with PC steel bar fixing holes 4 and reinforcing bar through holes on the circumference. 11 and a jack mounting bolt hole 13 for fixing a jack mounting bolt 12 is provided.

Generally, the type of pile that requires seismic performance at the head joint is a pile with high bending strength in which PC steel bars 8 are arranged very densely at a pitch of 50 CIN to 70 cwl.
Further, anchor reinforcing bars for fixing the joint end plates 10 to concrete are arranged between the PC steel bars 8, and have female threaded male threaded portions 6 between the main reinforcing bars.

The fixing end portion 4 of the PC steel rod has a protrusion 5, such as a conical shape, formed therein to fix the head 9 of the PC steel rod.

FIG. 4 shows a prestressed coupler nut of a type in which the required pieces 2 are combined to form a protrusion 5, such as a conical shape, for fixing the head 9 of the PC steel bar inside the fixed end 4 of the PC steel bar. 1 is shown.

The end structure of the prestressed concrete pile using the prestressed coupler nut 1 is as shown in the detailed cross-sectional view of FIG. The connecting end 3 of the male screw is fixed to the top, the upper end 3 is used as the fixing hole 3 for the upper structure connecting reinforcing bar 7, and the lower end is used as the fixing hole 4 for the PC steel bar.

FIG. 5 is an end plan view of a prestressed concrete pile, in which only reinforcing bar holes 11 are provided on the circumference of the joint end plate 10.

4. Use 3-4 effect prestressed coupler nut to fix PC steel rod fixing hole. It is almost impossible to add functionality such as embedding the jack mounting bolt hole 13-.

As mentioned above, the conventional headland structure has its limits in terms of improving various functions, and the PC steel bar fixing hole 4 and the jack mounting bolt hole 13, which is the introduction point for prestress, are far apart. Therefore, there remain problems such as the prestress cannot be directly introduced into the PCii rod 8.

3-3, Configuration The present invention will be explained based on typical embodiments.

As shown in Fig. 3, the prestressed coupler nut 1-1 is composed of a male threaded joint end 13 and a PCW4 rod fixed end 4, and connects the male thread 7.12 and the PC steel rod 8 at both ends. In the manufacturing process for introducing prestress, this male threaded joint end 13 is connected to the jack mounting bolt 12, and prestress from the jack is introduced, and is also introduced into the PCfIA rod 8, and is also connected to the footing. In the process of forming the pile cap joint, the superstructure connecting reinforcing bars 7 are joined to form a joining mechanism that effectively transmits prestress to the superstructure.

The male threaded joint end 13 has a female threaded part to which the male thread is joined inside, a reinforcing bar through hole 11 to be fixed to a dovetail threaded reinforcing bar hole provided in the joint end plate 10, and a superstructure connecting reinforcing bar fixation externally. By creating a completely new headland structure (see Figure 7) in which holes 3 are concentrated in one hole position, the conventional headland structure (see Figure 1) in which each hole is formed at a different position is improved. Formation of superstructure connection reinforcing bar fixing holes 3 in piles with high bending strength and many PC steel bars 8, which require good bonding performance with the superstructure, and solve various problems such as overcrowding of holes and the structure of the superstructure. This makes it possible to significantly improve the functionality of

By using a prestressed coupler nut 1 that can introduce prestress, it is possible to form a connection mechanism that performs two functions: introducing prestress to the PC steel bar 8 and transmitting prestress to the superstructure connection reinforcing bar 7. A highly earthquake-resistant headland structure with a stress transmission mechanism is constructed.

The number of holes provided in the joint end plate 10, such as the PC steel rod fixing holes 4, can be reduced to about 173 to 1/4, and the headland structure can be simplified, so the pile manufacturing process is simplified, and Decrease in yield strength and rigidity of the joint end plate 10 due to the formation of holes is reduced, and the prestress maintenance function is improved.

[Brief explanation of the drawing]

The drawings show typical embodiments of the present invention; FIG. 1 is a plan view of the end of a conventional prestressed concrete pile, FIG. 2 is a cross-sectional view of the end structure of a conventional prestressed concrete pile, Figures 3 and 4 are detailed diagrams of the prestressed coupler nut structure, Figure 5 is a plan view of the end of a prestressed concrete pile using a prestressed coupler nut, and Figures 6 and 7 are prestressed concrete using a prestressed coupler nut. It is a sectional view of the end structure of a pile. Code list Double-breasted rest coupler nut 2 - Piece forming a conical or other protrusion that fixes the head of the PC steel bar 3: Connection end of male thread and upper structure connection reinforcing bar fixing hole 4: Fixing of the PC steel bar End portion and fixing hole 5: A conical or other protrusion formed inside the coupler nut to fix the head of the PC steel rod 6: A coupler nut is inserted into the female threaded reinforcing bar hole provided in the joint end plate. Male threaded part 7 provided on the outside of the coupler nut for fixing: Male threaded part 8 of the superstructure joint reinforcing bar: PC steel bar 9: Head of the PC steel bar 10: Joint end plate...donut shape of the headland part Metal plate, also called end plate, seat plate, anchor ring, and metal joint plate. 11: Reinforcing bar through hole...A hole provided in the joint end plate for passing the PC steel rod, and the hole diameter is larger than the head diameter of the PC steel rod. 12: Jacket mounting bolt... Bolt that fixes the jack end that introduces prestress and the joint end plate 13: Male thread joint end and jack mounting bolt hole 1963 Patent Application No. 312053 2, Title of the invention End structure of ready-made concrete piles using pre-stressed planar yt 3, Person making the amendment 4, Agent address (residence) Name 5, Amendment order Date (Delivery Port): March 28, 1999 6. Drawings to be amended 7. Details of the amendment: All drawings should be clearly drawn in sufficiently rich black.

Claims (1)

[Claims] 2-1. The coupler nut has two different functions: a function of connecting with a male thread at one end and a function of fixing to a PC steel bar at the other end, The part has a female thread part on the inside that connects the male thread, and a male thread part on the outside that fixes the coupler nut in the mounting hole, and the fixing end of the other PC steel bar has a conical shape that fixes the head of the PC steel bar inside. A prestressed coupler nut 2-2 having a prestress introduction performance characterized by forming a protrusion such as the above, or by combining required parts to form a conical protrusion inside, and a male thread at one end. A prestressed coupler nut, which has two different functions: one to connect with the PC steel bar at the other end, and one to fix the PC steel bar at the other end, is used on the ready-made concrete pile, and this prestressed coupler nut is placed at the position where the PC steel bar is fixed on the joint end plate. Fix the male screw in the provided reinforcing bar hole with the joint end facing upward, and use the upper end of this fixed prestressed coupler nut as the fixing hole for the jack installation bolt and the reinforcing bar with the male thread, and use the lower end as the fixing hole for the PC steel bar. An end structure of a ready-made concrete pile characterized by