Prestressed composite pile and prestressed steel sheet pile wall
Technical Field
The utility model relates to a prestressing force composite pile and the prestressing force steel sheet pile wall that is formed by this prestressing force composite pile.
Background
When the deep foundation pit is used for enclosing, the conventional enclosure pile usually adopts a cast-in-situ bored pile or a cast-in-situ immersed tube pile, and a construction method of a cast-in-situ pile in a construction site is adopted, so that a foundation trench can be excavated after concrete reaches the strength even if the construction of the enclosure pile is completely finished, and the construction efficiency is low. The steel sheet pile has the advantages of high installation speed, no need of maintenance, capability of playing a supporting role after the installation is finished, and the like, and is widely applied to foundation pit engineering.
Compared with cast-in-place piles, underground continuous walls and other reinforced concrete supporting structures, the steel sheet piles are small in lateral rigidity and weak in deformation resistance, one or more supports are required to be arranged to prevent overlarge deformation from affecting the stability of the supporting structures, construction is complicated, and meanwhile construction cost is increased. Meanwhile, due to the defects, the steel sheet pile is generally applied to construction of underground structures within 2 layers, and is less applied to the underground structures with more than three layers.
SUMMERY OF THE UTILITY MODEL
In order to enlarge the application range of the steel sheet pile and reduce the construction cost and the engineering cost, the utility model firstly provides a prestressed composite pile, which comprises a first steel sheet pile arranged at the edge of a foundation pit, wherein the groove of the first steel sheet pile faces the outer side of the foundation pit, the inner side of the first steel sheet pile is provided with finish-rolled deformed steel bar, and the top of the first steel sheet pile is provided with a crown beam;
the lower end of the finish-rolled deformed steel bar is fixed at the lower end of the inner side of the first steel sheet pile, the upper end of the finish-rolled deformed steel bar is fixed on the crown beam, and the finish-rolled deformed steel bar is a prestressed reinforcement. In this application, the inboard of first steel sheet pile refers to the one side towards the inside direction of foundation ditch.
In this application, the inboard at first steel sheet pile has set up the finish rolling screw-thread steel, and carry out the stretch-draw to the finish rolling screw-thread steel, to the finish rolling screw-thread steel tensioning in-process, can make first steel sheet pile produce the bending that the outside of foundation ditch is outstanding, and produce prestressing force, improve the ability that first steel sheet pile resists the outside soil body pressure of foundation ditch, reduce the deflection of first steel sheet pile in foundation ditch work progress, can guarantee to strut under the stable condition of system from this, reduce and support quantity, reduce foundation ditch construction cost, and engineering cost. Utilize the prestressing force composite pile in this application, can make the steel sheet pile use in the construction of the underground structure more than the three-layer.
Further, for the convenience of fixing, the upper end of the finish-rolled deformed steel bar is fixed to the crown beam via an upper fixing nut. The finish-rolled deformed steel bar can be conveniently fixed on the crown beam by utilizing the upper fixing nut, after the finish-rolled deformed steel bar is tensioned, the upper fixing nut is screwed to the top end of the finish-rolled deformed steel bar, and the finish-rolled deformed steel bar can be kept in a set prestress range after the upper fixing nut is pressed on the crown beam.
Further, in order to prevent the upper fixing nut from being sunk into the crown beam and reduce the prestress of finish rolling deformed steel bar, a steel gasket is arranged between the upper fixing nut and the crown beam in a cushioning mode.
Further, a lower fixing nut is screwed at the lower end of the finish-rolled deformed steel bar, and the lower fixing nut is welded at the lower end of the inner side face of the first steel sheet pile. This design can be conveniently be connected to first steel sheet pile with the finish rolling screw-thread steel to when avoiding welding the finish rolling screw-thread steel on first steel sheet pile, the damage that causes. In addition, the lower fixing nut can be conveniently cut off to reuse the first steel sheet pile.
Furthermore, in order to avoid the finish rolling deformed steel bar from being attached to the inner side surface of the first steel sheet pile and influence the tensioning of the finish rolling deformed steel bar, at least one steel support is arranged between the finish rolling deformed steel bar and the first steel sheet pile in a cushioning mode, and the steel support is attached to the inner side surface of the first steel sheet pile. Furthermore, at least two steel supports are arranged between the finish-rolled deformed steel bar and the first steel sheet pile in a cushioning mode, and the at least two steel supports are arranged at intervals in the vertical direction.
Specifically, the distance between two adjacent steel supports is 200-400 mm. Within the distance range, the distance between the finish-rolled deformed steel bar and the first steel sheet pile can be ensured, and the tensioning can be smoothly carried out.
Further, the steel support is located in the area between the bottom surface of the foundation pit and the crown beam. The first steel sheet pile is subjected to inward external force and is concentrated in the area of the upper portion of the bottom surface of the foundation pit, and the first steel sheet pile can generate outward prestress as long as the distance between the part, located at the upper portion of the bottom surface of the foundation pit, of the finish-rolled deformed steel bar and the first steel sheet pile is ensured, and the resistance of the first steel sheet pile to external soil body pressure is improved.
Furthermore, in order to avoid the finish rolling deformed steel bar from being bonded on the crown beam and influencing the tensioning of the finish rolling deformed steel bar, the finish rolling deformed steel bar is sleeved with protective sleeves, and the protective sleeves penetrate through the upper side and the lower side of the crown beam.
Secondly, this application still discloses a prestressing force steel sheet pile wall, it includes a plurality of above-mentioned any one technical scheme of prestressing force combination pile that the interval set up at the foundation ditch edge, be provided with the second steel sheet pile between adjacent prestressing force combination pile, the recess of this second steel sheet pile is inboard towards the foundation ditch. Preferably, the first steel sheet pile and the second steel sheet pile are engaged with each other. Due to the arrangement of the prestressed steel bars, the capability of the first steel sheet pile for resisting the pressure of the soil outside the foundation pit is improved, so that the capability of the prestressed steel sheet pile wall for resisting the pressure of the soil outside the foundation pit is improved, and the steel sheet pile wall can be applied to the construction process of an underground structure with more than three layers.
Drawings
Fig. 1 is a schematic structural diagram of an embodiment of the present invention.
Fig. 2 is a left side view of fig. 1.
Fig. 3 is a view along a-a in fig. 1.
Fig. 4 is a view along the direction B-B in fig. 1.
Fig. 5 is an enlarged view of a portion C in fig. 1.
Detailed Description
Referring to fig. 1-5, the prestressed steel sheet pile wall 11 includes a plurality of prestressed composite piles disposed at intervals at the edge of the foundation pit, a second steel sheet pile 18 is disposed between adjacent prestressed composite piles, and a second groove 182 of the second steel sheet pile 18 faces the inner side of the foundation pit.
Referring to fig. 1 to 5, the prestressed composite pile includes a first steel sheet pile 17 and finish-rolled deformed steel 13 spaced apart from each other at the edge of the foundation pit 30, in this embodiment, the first steel sheet pile and the second steel sheet pile are both larsen steel sheet piles, and it is understood that in another embodiment, hat-shaped steel sheet piles may be used as the first steel sheet pile and the second steel sheet pile.
Wherein the first groove 172 of the first steel sheet pile 17 faces the outside of the foundation pit. And a crown beam 21 is arranged at the top of the first steel sheet pile and the second steel sheet pile. In fig. 1, reference numeral 100 denotes the ground.
A lower fixing nut 12 is screwed to the lower end of the finish-rolled deformed steel bar 13, and the lower fixing nut 12 is welded to the lower end of the inner surface 171 of the first steel sheet pile. Namely, the lower end of the finish-rolled deformed steel bar is fixed at the lower end of the inner side of the first steel sheet pile. The upper end of the finish-rolled deformed steel bar 13 is fixed to the crown beam 21 after passing upward through the crown beam 21, and the finish-rolled deformed steel bar is a prestressed reinforcement.
Specifically, in the present embodiment, the upper end of the finish-rolled deformed steel bar 13 is fixed to the crown beam via an upper fixing nut 15, the upper fixing nut 15 is supported by the crown beam 21, and a steel washer 14 is interposed between the upper fixing nut 15 and the crown beam 21.
And a plurality of steel supports 16 are padded between the finish-rolled deformed steel 13 and the first steel sheet pile 17, and the steel supports 16 extend along the horizontal direction and are attached to the inner side surface of the first steel sheet pile. For clarity, the steel support 16 is shown as a black line in fig. 2 and the steel support 16 is shown as a black dot in fig. 5.
This steel support is in order to avoid the laminating of finish rolling deformed steel 13 on the medial surface of first steel sheet pile, has certain distance between the medial surface of in order to guarantee finish rolling deformed steel 13 and first steel sheet pile, and in vertical direction, distance control between two upper and lower adjacent steel supports is between 200 manger plate mm, specifically in this embodiment, and the distance between two upper and lower adjacent steel supports is 300 mm. The steel support is only provided in the area between the foundation pit floor 31 and the crown beam 21.
In order to prevent the finish-rolled deformed steel bar from being bonded to the crown beam, a protective sleeve 23 is sleeved on the finish-rolled deformed steel bar, and the protective sleeve 23 penetrates through the upper side and the lower side of the crown beam. In this embodiment, the protective sleeve is made of a plastic tube. A horizontal brace 22 is bridged on the inner side of the crown beam 21.
In the construction of the prestressed steel sheet pile wall in the embodiment, the construction is performed according to the following steps:
(1) and welding a lower fixing nut 12 to the lower end of the inner side surface of the first steel sheet pile, and then screwing the lower end of the finish-rolled deformed steel bar on the lower fixing nut 12, so that the finish-rolled deformed steel bar extends towards the upper end of the first steel sheet pile along the length direction of the first steel sheet pile.
(2) And (4) sinking the first steel sheet pile and the second steel sheet pile carrying the finish-rolled deformed steel bar at set positions.
(3) And sleeving a protective sleeve on the finish-rolled deformed steel bar, positioning the protective sleeve at the joint position of the protective sleeve and the crown beam, and then pouring the crown beam.
(4) And (3) when the strength of the crown beam reaches the set strength, performing prestress tensioning on the finish-rolled deformed steel bar, and anchoring by using an upper fixing nut.
(5) And excavating the foundation pit and constructing the main structure.
(6) And after the main structure is constructed above the ground, pulling out the prestressed composite pile and the second steel sheet pile.