Prestressed wale dismantling and replacing structure and method
(1) technical field
The present invention relates to a kind of architectural engineering pit supporting and protection structure and job practices thereof.
(2) background technology
In foundation engineering, traditional deep foundation pit support usually adopts the pile anchor breast wall structure, makes some roads prestressed anchor between slope protection pile, is anchored at slope protection pile by the shaped steel waist rail.When engineering works, when constructing shaped steel waist rail position, just must be removed it during as the structure outer edge with pile body.And this moment, if prestressed anchor is also playing effect, removing the shaped steel waist rail rashly will influence construction safety.In order to prevent that engineering accident from taking place, and usually delays the duration.
(3) summary of the invention
The purpose of this invention is to provide a kind of prestressed wale dismantling and replacing structure and method, mainly solve in the pile anchor breast wall structure, remove the technical problem that the shaped steel waist rail can influence construction safety.
The object of the present invention is achieved like this:
A kind of prestressed wale dismantling and replacing structure, the slope protection pile (1) that the foundation ditch inside wall has a row to be provided with at interval, have one to arrange the prestressed anchor (2) that stretches in the foundation ditch inside wall at inter-pile soil body (12), each prestressed anchor wants the shaped steel waist rail (3) of dismantling and replacing to be anchored at foundation ditch inside wall waist, it is characterized in that: between two slope protection pile, be arranged side by side a concrete waist rail (9) at shaped steel waist rail (3) by the soil body one side, this concrete waist rail (9) is poured into a mould with the prestress wire (6) in the prestressed anchor (2) and is connected, and prestress wire (6) has pre-buried anchor (5) at the cast connecting portion.
A kind of prestressed wale dismantling and replacing method, at the foundation ditch inside wall the one row slope protection pile (1) of setting is at interval arranged, in the inter-pile soil body, there is a row to stretch into the prestressed anchor (2) of foundation ditch inside wall, in the inter-pile soil body, prestressed anchor (2) is arranged perpendicular to the foundation ditch inside wall, each prestressed anchor wants the shaped steel waist rail (3) of dismantling and replacing to be anchored at foundation ditch inside wall waist, it is characterized in that the dismantling and replacing step is:
Step 1, earlier at the rear portion of shaped steel waist rail (3) by the soil body one side, between slope protection pile, the middle position of prestressed anchor (2) cuts away a rejecting inter-pile soil body (10) wide outside and narrow inside, the partial prestressing steel strand (6) of prestressed anchor (2) are exposed, and the crust of prestress wire (6) is cleaned out;
Step 2, the prestress wire (6) that will expose are tightened with fastener (4);
Step 3, in the fastener inboard, perpendicular to prestress wire (6), insert pre-buried anchor;
Step 4, with the shaped steel waist rail side by side, reinforcing bar (13) and three limit cover stirrups (15) in the position colligation concrete waist rail of the disallowable soil body;
Step 5, formwork are at the medial branch side form (14) of shaped steel waist rail (3);
Step 6, in side form pour concrete, make concrete waist rail (9);
After step 7, the concrete strength for the treatment of the concrete waist rail reach C20, cut off the prestress wire (6) in the new poured concrete waist rail outside
Step 8, dismounting shaped steel waist rail (3) are finished the waist rail replacement.
Optimized technical scheme:
In the above-mentioned steps 1, reject inter-pile soil body (10) depth and can be 500~600mm, highly can be 200-400mm, the bottom can be cut flat, and top can be slope shape.
In the above-mentioned steps 2, can clog steel bar end in the gap in the prestress wire (6), available fastener (4) is tightened prestress wire;
In the above-mentioned steps 3, pre-buried anchor (5) can be bar dowel rod, steel bar end or the steel plate that intersects more than 2.
In the above-mentioned steps 4, the reinforcing bar (13) in the concrete waist rail can be elongated setting, not building concrete with slope protection pile outside interface portion, is exposed at the slope protection pile outside, and two reinforcing bars can be fixing with three limit cover stirrups (15).
In the above-mentioned steps 5, unsettled at the soil body of predetermined fluid concrete waist rail bottom, prop up bed die; The bottom soil body is solid, can directly build on soil.
In the above-mentioned steps 6, the sectional dimension of concrete waist rail is not less than 300 * 500mm.
In step 7, the method of cutting off prestress wire (6) can be: with the electrode holder spreading, be positioned at the middle drawknot point cut-out prestress wire of shaped steel waist rail earlier with electric welding, tower crane hangs the shaped steel waist rail, electricity consumption is welded in the drawknot point that is positioned at shaped steel waist rail inboard and cuts off prestress wire again, at last the shaped steel waist rail is hung out.
Beneficial effect of the present invention: prestressed wale dismantling and replacing method of the present invention adopts gap concreting waist rail between stake, prestressed anchor is anchored in the concrete breast beam, suitable configuration reinforcement in the waist rail, utilize the shear resistance of concrete breast beam, the anchored force of prestressed anchor is transferred on the pile body.Shaped steel wale dismantling and replacing technology has the reduction of erection time, and disposal cost is cheap, safe and reliable, simple and easy to do advantage.
(4) description of drawings
Fig. 1 is the concrete waist rail facade structures schematic diagram after the replacement;
Fig. 2 is the structural representation of concrete waist rail at horizontal profile;
Fig. 3 is the A-A generalized section of concrete waist rail arrangement of reinforcement among Fig. 2.
Fig. 4 is the shaped steel waist rail facade structures schematic diagram before the replacement.
Fig. 5 is the schematic diagram of the shaped steel waist rail horizontal profile before the replacement.
Fig. 6 is the schematic diagram of rejecting inter-pile soil body and formwork position.
Fig. 7 is a chucking prestress wire and the schematic diagram that inserts the bar dowel rod before the fluid concrete.
Among the figure: 1-slope protection pile, 2-prestressed anchor, 3-shaped steel waist rail, 4-fastener, the pre-buried anchor of 5-, 6-prestress wire, 7-backing plate, 8-anchor head, 9-concrete waist rail, 10-reject the inter-pile soil body, 11-sprays the disconnected stubble of reinforcing bar, 14-side form, 15-three limit cover stirrups, 16-prestress wire in concrete dado, 12-inter-pile soil, the 13-concrete waist rail.
(5) specific embodiment
Embodiment is referring to shown in Fig. 4-5, this prestressed wale dismantling and replacing structure, slope protection pile 1 and one deck that the foundation ditch inside wall has a row to be provided with at interval spray concrete dado 11, in inter-pile soil 12, have one to arrange the prestressed anchor 2 that stretches in the foundation ditch inside wall, perpendicular to the foundation ditch inside wall prestressed anchor 2 is arranged in the inter-pile soil body, each prestressed anchor wants the shaped steel waist rail 3 of dismantling and replacing to be anchored at foundation ditch inside wall waist.
Referring to Fig. 1-2, between two slope protection pile 1, be arranged side by side a concrete waist rail 9 by the soil body one side at the shaped steel waist rail, this concrete waist rail 9 is poured into a mould with the prestress wire 6 in the prestressed anchor and is connected, and prestress wire 6 has pre-buried anchor 5 at the cast connecting portion.Dotted line is the outer edge of concrete waist rail 9.
This prestressed wale dismantling and replacing method, at the foundation ditch inside wall the one row slope protection pile (1) of setting is at interval arranged, in the inter-pile soil body, there is a row to stretch into the prestressed anchor (2) of foundation ditch inside wall, in the inter-pile soil body, prestressed anchor (2) is arranged perpendicular to the foundation ditch inside wall, each prestressed anchor wants the shaped steel waist rail (3) of dismantling and replacing to be anchored at foundation ditch inside wall waist, it is characterized in that the dismantling and replacing step is:
Step 1 is referring to Fig. 6, earlier at the rear portion of shaped steel waist rail (3) by the soil body one side, between slope protection pile, the middle position of prestressed anchor (2) cuts away a rejecting inter-pile soil body (10) wide outside and narrow inside, the partial prestressing steel strand (6) of prestressed anchor (2) are exposed, and the crust of prestress wire (6) is cleaned out.In the above-mentioned steps 1, press concrete slope protection pile outermost and calculate, rejecting inter-pile soil body (10) depth is 500~600mm, is 200-400mm highly, and the bottom is cut flat, and top is slope shape.
Step 2 is referring to Fig. 7, and the prestress wire that will expose (6) is tightened with φ 48 fasteners (4).In the above-mentioned steps 2,, clog 2~3 long φ 16 steel bar ends of 250mm in the gap in prestress wire (6), prestress wire must be tightened with fastener (4) if prestressed reinforcement is gapped.The as close as possible concrete breast beam of fastener (4) outside.Exceed with the not outstanding slope protection pile outside, to guarantee not occur slippage between steel strand and the buckle.It is that concrete disperses reinforcing bar to concentrate anchored force towards periphery that steel bar end is inserted at the buckle rear portion, should be adjacent to buckle as far as possible.
Step 3 in the fastener inboard, perpendicular to prestress wire (6), is inserted pre-buried anchor referring to Fig. 7.In the above-mentioned steps 3, pre-buried anchor (5) is bar dowel rod, steel bar end or the steel plate that intersects more than 2.
Step 4 is referring to Fig. 2, Fig. 3, with the shaped steel waist rail side by side, reinforcing bar (13) and three limit cover stirrups (15) in the position colligation concrete waist rail of the disallowable soil body.Reinforcing bar (13) in the concrete waist rail is the elongated settings of 2 φ 20mm, can not building concrete with slope protection pile outside interface portion, is exposed at the slope protection pile outside.Two reinforcing bars are fixing with φ 8mm three limit cover stirrups (15), and the spacing of three limit cover stirrups is 150mm.
Step 5 is referring to Fig. 6, and formwork is at the medial branch side form (14) of shaped steel waist rail (3).In the above-mentioned steps 5, unsettled at the soil body of predetermined fluid concrete waist rail bottom, prop up bed die; The bottom soil body is solid, can directly build on soil.Can utilize the shaped steel waist rail to do a top.
Step 6 is referring to Fig. 6, and pour concrete in the dotted line position of Fig. 6 in side form is made concrete waist rail (9).In the above-mentioned steps 6, the sectional dimension of concrete waist rail is not less than 300 * 500mm.
Step 7 after the concrete strength for the treatment of the concrete waist rail reaches C20, is cut off the prestress wire (6) in the new poured concrete waist rail outside.The method of cutting off prestress wire (6) is: earlier with thin flitch with more than the electric welding electrode holder spreading to a meter, be positioned at the middle drawknot point cut-out prestress wire of shaped steel waist rail earlier with electric welding, tower crane hangs the shaped steel waist rail, electricity consumption is welded in the drawknot point that is positioned at shaped steel waist rail inboard and cuts off prestress wire again, at last the shaped steel waist rail is hung out.
Whether step 8 is removed shaped steel waist rail (3) referring to Fig. 1,2, observe the disconnected stubble 16 of prestress wire and shrink.If shrinkage phenomenon does not appear in the disconnected stubble of prestress wire, illustrate that waist rail replacement work finishes.