A kind of prestressing force support system for elongated rectangular shape foundation ditch
Technical field
The invention belongs to field of civil engineering, be specifically related to the prestressing force supporting and protection structure of foundation ditch.
Background technology
The mode that existing pattern foundation pit supporting structure mode mostly adopts is, in the surrounding of foundation ditch, reinforced concrete fortifield village purlin is set, arrange netted steel pipe support enclosing in purlin week again, when it is not enough, steel pipe consumption is large, install, remove trouble, and it is large to take up space, and is unfavorable for soil excavation in foundation ditch, can not apply prestressing force to foundation pit side-wall well, support strength is low, conventionally can only increase support force by the density that increases steel pipe layout; And when different pattern foundation pit supporting structure, need use the steel pipe of different size, steel pipe repeat usage is low, causes the costly of pattern foundation pit supporting structure.
Summary of the invention
Technical problem to be solved by this invention is: the deficiency existing for prior art, and provide a kind of and install, remove conveniently, occupy foundation ditch space little, the foundation ditch prestressing force supporting and protection structure that supporting intensity is high and the supporting section bar rate of recovery is high.
For realizing the present invention's object, be achieved by the following technical solutions: a kind of prestressing force support system for elongated rectangular shape foundation ditch, include the cement mixing pile of squeezing into along foundation ditch periphery downwards, the capping beam of reinforced concrete structure is built on cement mixing pile top, in capping beam, be connected with in week and enclose purlin shaped steel, enclose purlin shaped steel and be fixedly connected with capping beam by rebar connector.
The described purlin shaped steel that encloses is H shaped steel, on the edge of a wing of its both sides, equidistantly offer connecting hole group, each connecting hole group is by two connecting hole cell formations, there are six connecting holes each connecting hole unit, six connecting holes are along enclosing the formal distribution that purlin shaped steel length direction is listed as with two rows three, laterally the distance between two adjacent connecting holes is a, and longitudinally the distance between two adjacent connecting holes is 2a; The two ends of enclosing purlin shaped steel are fixedly welded with junction plate, offer four connecting holes with two row's two row formal distributions on junction plate, and the distance between horizontal, longitudinal two adjacent connecting holes is 2a; Adjacent enclosing between purlin shaped steel used four groups of bolts coaxially to connect by junction plate.
Described rebar connector includes L shaped reinforcing bar, reinforcing bar in minor face and the capping beam of L shaped reinforcing bar is welded and fixed, end, the long limit coaxial welding of L shaped reinforcing bar has the female reinforcing bar connector that can attachment screw of tool, thereby is connected with reinforcing bar connector and will encloses purlin shaped steel and capping beam is fixed through the screw that encloses purlin shaped steel; Reinforcing bar in minor face and the capping beam of L shaped reinforcing bar welds and is cemented in the concrete of capping beam, and bonding strength is high to be not easy.
Connect by two triangle connection elements enclosing between purlin shaped steel of foundation ditch vertex position both sides, one of them triangle connection element is connected between two junction plates that enclose purlin shaped steel end, and another triangle connection element is connected between two sides of enclosing the adjacent end of purlin shaped steel; Two triangle connection elements coordinate, and make two of angle position enclose purlin shaped steel and are connected firmly, and are not easy loosening or distortion.
Described triangle connection element includes the linking arm of two vertical weldings, offers six connecting holes on each linking arm, is vertically welded with the gusset plate of an isosceles right triangle between two linking arms.
Be provided with 3 groups of angle braces at foundation ditch near each summit place, include 2 groups of sub-thread angle braces and 1 group of three strands of angle brace.
Described sub-thread angle brace includes two the first angle brace seats and a strut, the first angle brace seat is bolted and is enclosing on purlin shaped steel, strut and foundation ditch summit two gusset purlin shaped steel form an isosceles right triangle, one end of strut and a first angle brace seat are bolted, and between the other end of strut and another the first angle brace seat, are connected with a jack.
Between the strut of two sub-thread angle braces, be connected with two channel-section steels, two channel-section steels are mutually vertical, and between channel-section steel and strut shape is in angle of 45 degrees.
The first described angle brace seat surrounds an isosceles right triangle by three block plate head and the tail successively welding, three block plate intermediate vertical are welded with a stiffener, be positioned on the steel plate of hypotenuse and offer six connecting holes, six connecting holes along hypotenuse length direction with two row's three column distributions, laterally the distance of adjacent two connecting holes is a, and longitudinally the distance of adjacent two connecting holes is 2a; Be positioned on the steel plate of a right-angle side and offer four connecting holes; Four connecting holes are with two row's two column distributions, and distances horizontal, longitudinally adjacent two connecting holes are 2a; And the position deflection that is positioned at six connecting holes on the steel plate of hypotenuse is not offered steel plate one side of connecting hole; As shown in Figure 9, the first angle brace is sat and is connected with strut and is produced after prestressing force by jack, pressure mainly concentrates on steel plate on the right-angle side that has connecting hole and the right side part of hypotenuse upper steel plate, therefore it is the most reasonable that the connecting hole of the steel plate on hypotenuse is arranged on the position of keeping right, do not need too much connecting hole on the one hand, ensured again on the other hand bonding strength.
Three strands of described angle braces include two multiply angle brace seats and three struts; Described multiply angle brace seat is bolted two adjacent enclosing between purlin shaped steel, and multiply angle brace seat is connected with capping beam by rebar connector; Each multiply angle brace seat supported underneath has crossbeam, and described crossbeam is connected between two cement mixing piles, and crossbeam and enclose purlin shaped steel and be arranged in parallel; Described crossbeam is with to enclose purlin shaped steel parallel, and the obstruction to excavator while having reduced like this excavation of foundation pit, is beneficial to and raises the efficiency.
Described cement mixing pile upper portion side wall is connected with bracket part, and bracket part is connected with the H shaped steel in cement mixing pile by bolt; Described beam erection is on bracket part, and crossbeam and bracket part are bolted;
Between three described struts, be evenly connected with 4 and connect cover plate, connect cover plate mutually vertical with strut; Between three described struts, be also connected with 3 channel-section steels, each channel-section steel is between two adjacent connection cover plates.
Described multiply angle brace seat is the second angle brace seat or trivet seat.
Described trivet seat is welded successively and is formed by three sections of H shaped steel, and the web of three sections of H shaped steel is in the same plane, and three sections of H shaped steel surround an isosceles right triangle; The H shaped steel e two ends that are positioned at hypotenuse stretch out, and end is fixedly welded with junction plate, and a H shaped steel f end that is positioned at right-angle side is also connected with a junction plate; On the edge of a wing of each H shaped steel periphery of described trivet seat, offer connecting hole; On the H shaped steel f edge of a wing, offer six connecting hole unit, there are four connecting holes each connecting hole unit, and the distance in each connecting hole unit between horizontal, longitudinal two connecting holes is 2a; Be positioned on the H shaped steel g edge of a wing of another right-angle side and offer five connecting hole unit; The interlude on the H shaped steel e edge of a wing offers seven connecting hole unit, and the two end portions on the H shaped steel e edge of a wing offers two group of two connecting hole of arranging eight row, and the distance of horizontal two adjacent connecting holes is a, and the distance of longitudinal two adjacent connecting holes is 2a; Between the web of each H shaped steel and the edge of a wing, be also welded with multiple reinforcing gussets, reinforcing gusset is positioned at the center of each connecting hole unit transverse; Between H shaped steel f and H shaped steel e, be welded with a reinforcing H shaped steel a parallel with H shaped steel g, between reinforcing H shaped steel a and H shaped steel e, H shaped steel g, be welded with two sections and reinforce H shaped steel b; Reinforce H shaped steel a, reinforce the web of H shaped steel b and the web isoplanar of H shaped steel e, reinforce H shaped steel a and reinforce vertical setting of H shaped steel b, and between reinforcing H shaped steel a two edges of a wing, the corresponding position that reinforces the H shaped steel b edge of a wing is welded with reinforcing gusset; Between each adjacent H shaped steel of trivet seat, and reinforce H shaped steel a and H shaped steel f junction, reinforcing H shaped steel b and H shaped steel g junction and be all welded with and the isoplanar triangular reinforced steel plate of web; Described trivet holder structure is firm, and mechanical strength is high, and owing to being provided with the reinforcing H shaped steel a of right-angled intersection form and reinforcing H shaped steel b, makes the H type steel on each limit all can bear larger pressure.
On the long limit of foundation ditch, be provided with two or more fish belly sill devices, fish belly sill device includes 2 the second angle brace seats, 5 web member supports between two the second angle brace seats, and be fixed between two the second angle brace seats and to each web member support and apply prestressed steel strand.
The second described angle brace seat is welded and forms successively by three sections of H shaped steel, and the web of three sections of H shaped steel is in the same plane, and three sections of H shaped steel surround an isosceles right triangle; The H shaped steel i that is positioned at hypotenuse is welded with a H shaped steel h in 1/3 position on the edge of a wing outwardly, and the both ends of H shaped steel h and H shaped steel i are all welded with junction plate; H shaped steel i is positioned at H shaped steel h mono-side and on the edge of a wing, offers 2 group of two connecting hole of arranging four row outwardly, and the distance of horizontal two adjacent connecting holes is a, and the distance of longitudinal two adjacent connecting holes is 2a; H shaped steel i is positioned at H shaped steel h opposite side and offers one group of two connecting hole of arranging 11 row and one group two and arranging six row outwardly on the edge of a wing; Between the web of H shaped steel i inner side and the edge of a wing, be welded with multiple reinforcing gussets, reinforce gusset and be positioned at the position at H shaped steel h two ends, and position between two adjacent groups connecting hole; The H shaped steel j end that is positioned at right-angle side is welded with junction plate, and the H shaped steel j edge of a wing outwardly offers six group of two connecting hole of arranging two row; The end of H shaped steel k and the edge of a wing vertical welding of H shaped steel j next-door neighbour end that are positioned at another right-angle side, the other end of the k of H shaped steel and H shaped steel i are away from one end welding of H shaped steel h; The H shaped steel k edge of a wing outwardly offers three group of two connecting hole of arranging two row; H shaped steel k is welded with a guide plate passing for steel strand near the end position of H shaped steel i, and H shaped steel i is welded with a steel strand fixed head near one end of H shaped steel k; Between H shaped steel i, H shaped steel j and H shaped steel k, be welded with a junction steel plate, the position that junction steel plate is positioned at the second angle brace seat middle part is provided with two steel strand anchorages; Described steel strand anchorage applies pulling force to steel strand, makes each web member support produce prestressing force to the cement mixing pile metope of foundation pit side-wall, ensures that body of wall does not firmly tilt or collapses.Described steel strand end is divided into two strands through after guide plate, and one is strained by ground tackle, and another strand is fixed on steel strand fixed head after ground tackle tension.
Described web member support includes lower-cord beam, with lower-cord beam web member connected vertically, be connected the oblique fulcrum bar of web member and lower-cord beam, also comprise and the extension rod of the coaxial adjustment web member length being connected of web member, and be connected to the steel strand positioning head of extension rod end; Each lower-cord beam end connects successively, and the lower-cord beam that is positioned at outermost end is connected with the second angle brace seat end; Described extension rod can be adjusted the effective length of web member as required, thereby makes steel strand have the radian needing, and the corner dimension between steel strand and web member is suitable.
The below of described each web member is also supported with angle-table bracket, angle-table bracket and the fixing welding of H shaped steel being inserted in cement mixing pile; Described steel strand coordinate pulling force that web member support produces on horizontal plane, and angle-table bracket can not produce web member support to teetertotter or be loosening.
In 5 described web member supports, be positioned at middle web member support and there is the longest web member and extension rod, be positioned at outermost web member support and there is the shortest web member and extension rod.
Described steel strand are successively on the steel strand positioning head of each web member bracket end, and the two ends of steel strand are passed the guide plate on the second angle brace seat and are fixed on steel strand fixed head and steel strand anchorage.
Described steel strand form symmetrical six parts between two the second angle brace seats and 5 web member supports, be followed successively by symmetrical line a, line b and line c from middle toward both sides, between line a and extension rod, form the angle of 82 degree, between line b and extension rod, form the angle of 67 degree, between line c and extension rod, form the angle of 54 degree; Described steel strand coordinate web member support to be set to above-mentioned angle, have ensured enough prestressing force on the one hand, make on the other hand web member support entirety occupy less space, are beneficial to the excavation of excavator.
Two the second angle brace seats and 5 web member support supported underneath have and the crossbeam that encloses purlin shaped steel and be arranged in parallel, and described crossbeam is connected on cement mixing pile; Between the extension rod of three web member supports at middle part, be also connected with reinforcement; The extension rod that sets up both sides after steel strand positioning head due to steel strand can be bending in opposite directions, and described reinforcement makes extension rod not produce deformation, keeps lastingly stable support force.
On the minor face of foundation ditch, be provided with a fish belly sill device, fish belly sill device includes 2 the second angle brace seats, 3 web member supports between two the second angle brace seats, and be fixed between two the second angle brace seats and to each web member support and apply prestressed steel strand.
Described steel strand form symmetrical four parts between two the second angle brace seats and 3 web member supports, be followed successively by symmetrical line d and line e from middle toward both sides, between line d and extension rod, form the angle of 78 degree, between line e and extension rod, form the angle of 58 degree; Because the length of foundation ditch minor face is less, be set to larger angle to reduce the quantity of member therefore 3 web member supports steel strand are only set, and ensure the intensity supporting.
Two the second angle brace seats and 3 web member support supported underneath have and the crossbeam that encloses purlin shaped steel and be arranged in parallel, and described crossbeam is connected on cement mixing pile.
Between two long limits of foundation ditch, be provided with at least one group to support arrangement, to support arrangement, between two adjacent groups fish belly sill device, every group includes two Eight characters supports and is connected to two one group of struts between Eight characters support support arrangement.
Described Eight characters support includes two the second angle brace seats, a gusseted seat and connects two groups of struts of two the second angle brace seats and gusseted seat; Two described the second angle brace seats are bolted the enclosing between purlin shaped steel of installation site, and the second angle brace seat is connected with capping beam by rebar connector; Two described the second angle brace seats are the members of two the fish belly sill devices in the left and right sides simultaneously, make the second angle brace seat syndeton of fish belly sill device end of both sides more firm to support arrangement, guarantee that steel strand can apply enough large prestressing force.
Described gusseted seat is isosceles right triangle, each right-angle side of gusseted seat is connected with respectively three struts, three strut other ends are connected with a reinforcement H shaped steel, the position of corresponding three struts of reinforcement H shaped steel opposite side is connected with three and regulates H shaped steel, regulates the H shaped steel other end to be connected with the H shaped steel j of the second angle brace seat right-angle side; Between three struts of every group, be connected with three and connect cover plate; Described gusseted seat right angle vertex position is connected with one perpendicular to the strut that encloses purlin shaped steel, and the strut other end connects a jack, and the purlin shaped steel that encloses between jack and two the second angle brace seats is connected.
Between the gusseted seat of both sides Eight characters support, connect by four struts; Four strut supported underneath have the crossbeam vertical with strut, and crossbeam two ends are connected to two cement mixing pile tops, between two cement mixing piles, are connected with bridging.
Compared with prior art, the invention has the beneficial effects as follows: by angle brace being set in foundation ditch apex portion, in foundation ditch short side part, one group of fish belly sill device is set, divide two or more fish belly sill devices are set at the long leg of foundation ditch, and the position between two adjacent fish belly sill devices arranges support between two long limits, jointly foundation ditch is played to support action, described angle brace and to support by adjust jack produce prestressing force, described fish belly sill device by adjust steel strand elasticity produce prestressing force.The space that this kind of supporting and protection structure takies is on the whole little, is convenient to the excavation of foundation ditch, raises the efficiency, meanwhile, the member of supporting and protection structure is mostly standard-sized section bar, connects by bolt part, install, remove all very convenient, repeatedly recycling rate of waterused is high, has reduced on the whole the cost of pattern foundation pit supporting structure.
Brief description of the drawings
Fig. 1 is overall structure schematic diagram of the present invention.
Fig. 2 is the syndeton schematic diagram that encloses purlin shaped steel and capping beam.
Fig. 3 is the structural representation of rebar connector.
Fig. 4 is triangle connection element and the syndeton schematic diagram that encloses purlin shaped steel.
Fig. 5 is the structural representation of triangle connection element.
Fig. 6 is the structural representation of looking up direction of Fig. 5.
Fig. 7 is the angle brace structural representation of a vertex position of foundation ditch.
Fig. 8 is the structural representation of sub-thread angle brace.
Fig. 9 is the structural representation of the first angle brace seat.
Figure 10 is the structural representation of overlooking direction of Fig. 9.
Figure 11 is the structural representation of trivet seat.
Figure 12 is the syndeton schematic diagram of crossbeam.
Figure 13 is arranged on the structural representation of the fish belly sill device on the long limit of foundation ditch.
Figure 14 is the structural representation of the second angle brace seat.
Figure 15 is the structural representation of web member support.
Figure 16 is the mounting structure schematic diagram of web member support.
Figure 17 is arranged on the structural representation of the fish belly sill device of foundation ditch minor face.
Figure 18 is arranged on the structural representation to support arrangement between the long limit of foundation ditch two.
Figure 19 is the structural representation of Eight characters support.
Figure 20 is the mounting structure schematic diagram to support arrangement lower crossbeam.
Detailed description of the invention
With reference to the accompanying drawings the specific embodiment of the present invention is made a detailed explanation below.
According to shown in Fig. 1 to Figure 20, a kind of prestressing force support system for elongated rectangular shape foundation ditch described in the present embodiment, include the cement mixing pile 40 of squeezing into along foundation ditch periphery downwards, the capping beam of reinforced concrete structure is built on cement mixing pile top, in capping beam, be connected with in week and enclose purlin shaped steel 10, enclose purlin shaped steel and be fixedly connected with capping beam by rebar connector 70.
The described purlin shaped steel that encloses is H shaped steel, on the edge of a wing of its both sides, equidistantly offer connecting hole group, each connecting hole group is by two connecting hole cell formations, there are six connecting holes each connecting hole unit, six connecting holes are along enclosing the formal distribution that purlin shaped steel length direction is listed as with two rows three, laterally the distance between two adjacent connecting holes is a, and longitudinally the distance between two adjacent connecting holes is 2a; The two ends of enclosing purlin shaped steel are fixedly welded with junction plate 01, offer four connecting holes with two row's two row formal distributions on junction plate, and the distance between horizontal, longitudinal two adjacent connecting holes is 2a.
Described rebar connector includes L shaped reinforcing bar 701, reinforcing bar in minor face and the capping beam of L shaped reinforcing bar is welded and fixed, end, the long limit coaxial welding of L shaped reinforcing bar has the female reinforcing bar connector 702 that can attachment screw of tool, thereby is connected with reinforcing bar connector and will encloses purlin shaped steel and capping beam is fixed through the screw 703 that encloses purlin shaped steel.
Connect by two triangle connection elements 20 enclosing between purlin shaped steel of foundation ditch vertex position both sides, one of them triangle connection element is connected between two junction plates that enclose purlin shaped steel end, and another triangle connection element is connected between two sides of enclosing the adjacent end of purlin shaped steel.
Described triangle connection element includes the linking arm 202 of two vertical weldings, offers six connecting holes on each linking arm, is vertically welded with the gusset plate 201 of an isosceles right triangle between two linking arms.
Be provided with 3 groups of angle braces at foundation ditch near each summit place, include 2 groups of sub-thread angle braces and 1 group of three strands of angle brace.
Described sub-thread angle brace includes two the first angle brace seats 21 and a strut 11, the first angle brace seat is bolted and is enclosing on purlin shaped steel, strut and foundation ditch summit two gusset purlin shaped steel form an isosceles right triangle, one end of strut and a first angle brace seat are bolted, and between the other end of strut and another the first angle brace seat, are connected with a jack 30.
Between the strut of two sub-thread angle braces, be connected with 14, two channel-section steels of two channel-section steels mutually vertical, and between channel-section steel and strut 11 shape is in angle of 45 degrees.
The first described angle brace seat surrounds an isosceles right triangle by three block plate head and the tail successively welding, three block plate intermediate vertical are welded with a stiffener, be positioned on the steel plate of hypotenuse and offer six connecting holes, six connecting holes along hypotenuse length direction with two row's three column distributions, laterally the distance of adjacent two connecting holes is a, and longitudinally the distance of adjacent two connecting holes is 2a; Be positioned on the steel plate of a right-angle side and offer four connecting holes; Four connecting holes are with two row's two column distributions, and distances horizontal, longitudinally adjacent two connecting holes are 2a; And the position deflection that is positioned at six connecting holes on the steel plate of hypotenuse is not offered steel plate one side of connecting hole.
Three strands of described angle braces include two multiply angle brace seats and three struts; Described multiply angle brace seat is bolted two adjacent enclosing between purlin shaped steel, and multiply angle brace seat is connected with capping beam by rebar connector; Each multiply angle brace seat supported underneath has crossbeam 13, and described crossbeam is connected between two cement mixing piles 40, and crossbeam and enclose purlin shaped steel and be arranged in parallel.
Described cement mixing pile upper portion side wall is connected with bracket part, and bracket part is connected with the H shaped steel in cement mixing pile by bolt; Described beam erection is on bracket part, and crossbeam and bracket part are bolted.
Between three described struts, be evenly connected with 4 and connect cover plate, connect cover plate mutually vertical with strut; Between three described struts, be also connected with 3 channel-section steels, each channel-section steel is between two adjacent connection cover plates.
Described multiply angle brace seat is the second angle brace seat 22 or trivet seat 23.
Described trivet seat is welded successively and is formed by three sections of H shaped steel, and the web of three sections of H shaped steel is in the same plane, and three sections of H shaped steel surround an isosceles right triangle; The H shaped steel e234 two ends that are positioned at hypotenuse stretch out, and end is fixedly welded with junction plate, and a H shaped steel f235 end that is positioned at right-angle side is also connected with a junction plate; On the edge of a wing of each H shaped steel periphery of described trivet seat, offer connecting hole; On the H shaped steel f edge of a wing, offer six connecting hole unit, there are four connecting holes each connecting hole unit, and the distance in each connecting hole unit between horizontal, longitudinal two connecting holes is 2a; Be positioned on the H shaped steel g236 edge of a wing of another right-angle side and offer five connecting hole unit; The interlude on the H shaped steel e edge of a wing offers seven connecting hole unit, and the two end portions on the H shaped steel e edge of a wing offers two group of two connecting hole of arranging eight row, and the distance of horizontal two adjacent connecting holes is a, and the distance of longitudinal two adjacent connecting holes is 2a; Between the web of each H shaped steel and the edge of a wing, be also welded with multiple reinforcing gussets, reinforcing gusset is positioned at the center of each connecting hole unit transverse; Between H shaped steel f and H shaped steel e, be welded with a reinforcing H shaped steel a231 parallel with H shaped steel g, between reinforcing H shaped steel a and H shaped steel e, H shaped steel g, be welded with two sections and reinforce H shaped steel b232; Reinforce H shaped steel a, reinforce the web of H shaped steel b and the web isoplanar of H shaped steel e, reinforce H shaped steel a and reinforce vertical setting of H shaped steel b, and between reinforcing H shaped steel a two edges of a wing, the corresponding position that reinforces the H shaped steel b edge of a wing is welded with reinforcing gusset; Between each adjacent H shaped steel of trivet seat, and reinforce H shaped steel a and H shaped steel f junction, reinforcing H shaped steel b and H shaped steel g junction and be all welded with and the isoplanar triangular reinforced steel plate 233 of web.
On the long limit of foundation ditch, be provided with two or more fish belly sill devices, fish belly sill device includes 2 the second angle brace seats 22,5 web member supports 17 between two the second angle brace seats, and be fixed between two the second angle brace seats and to each web member support and apply prestressed steel strand 50.
The second described angle brace seat is welded and forms successively by three sections of H shaped steel, and the web of three sections of H shaped steel is in the same plane, and three sections of H shaped steel surround an isosceles right triangle; The H shaped steel i221 that is positioned at hypotenuse is welded with a H shaped steel h222 in 1/3 position on the edge of a wing outwardly, and the both ends of H shaped steel h and H shaped steel i are all welded with junction plate; H shaped steel i is positioned at H shaped steel h mono-side and on the edge of a wing, offers 2 group of two connecting hole of arranging four row outwardly, and the distance of horizontal two adjacent connecting holes is a, and the distance of longitudinal two adjacent connecting holes is 2a; H shaped steel i is positioned at H shaped steel h opposite side and offers one group of two connecting hole of arranging 11 row and one group two and arranging six row outwardly on the edge of a wing; Between the web of H shaped steel i inner side and the edge of a wing, be welded with multiple reinforcing gussets, reinforce gusset and be positioned at the position at H shaped steel h two ends, and position between two adjacent groups connecting hole; The H shaped steel j223 end that is positioned at right-angle side is welded with junction plate, and the H shaped steel j edge of a wing outwardly offers six group of two connecting hole of arranging two row; The end of H shaped steel k224 and the edge of a wing vertical welding of H shaped steel j next-door neighbour end that are positioned at another right-angle side, the other end of the k of H shaped steel and H shaped steel i are away from one end welding of H shaped steel h; The H shaped steel k edge of a wing outwardly offers three group of two connecting hole of arranging two row; H shaped steel k is welded with a guide plate 225 passing for steel strand near the end position of H shaped steel i, and H shaped steel i is welded with a steel strand fixed head 226 near one end of H shaped steel k; Between H shaped steel i, H shaped steel j and H shaped steel k, be welded with a junction steel plate 227, the position that junction steel plate is positioned at the second angle brace seat middle part is provided with two steel strand anchorages 228.
Described web member support 17 includes lower-cord beam 171, with lower-cord beam web member 173 connected vertically, be connected the oblique fulcrum bar 172 of web member and lower-cord beam, also comprise and the extension rod 174 of the coaxial adjustment web member length being connected of web member, and be connected to the steel strand positioning head 175 of extension rod end; Each lower-cord beam end connects successively, and the lower-cord beam that is positioned at outermost end is connected with the second angle brace seat end.
The below of described each web member is also supported with angle-table bracket 170, angle-table bracket and the fixing welding of H shaped steel being inserted in cement mixing pile 40.
In 5 described web member supports, be positioned at middle web member support and there is the longest web member and extension rod, be positioned at outermost web member support and there is the shortest web member and extension rod.
Described steel strand are successively on the steel strand positioning head of each web member bracket end, and the two ends of steel strand are passed the guide plate on the second angle brace seat and are fixed on steel strand fixed head and steel strand anchorage.
Described steel strand form symmetrical six parts between two the second angle brace seats and 5 web member supports, be followed successively by symmetrical line a501, line b502 and line c503 from middle toward both sides, between line a and extension rod, form the angle of 82 degree, between line b and extension rod, form the angle of 67 degree, between line c and extension rod, form the angle of 54 degree.
Two the second angle brace seats and 5 web member support supported underneath have and the crossbeam that encloses purlin shaped steel and be arranged in parallel, and described crossbeam is connected on cement mixing pile; Between the extension rod of three web member supports at middle part, be also connected with reinforcement.
On the minor face of foundation ditch, be provided with a fish belly sill device, fish belly sill device includes 2 the second angle brace seats, 3 web member supports between two the second angle brace seats, and be fixed between two the second angle brace seats and to each web member support and apply prestressed steel strand.
Described steel strand form symmetrical four parts between two the second angle brace seats and 3 web member supports, be followed successively by symmetrical line d504 and line e505 from middle toward both sides, between line d and extension rod, form the angle of 78 degree, between line e and extension rod, form the angle of 58 degree.
Two the second angle brace seats and 3 web member support supported underneath have and the crossbeam that encloses purlin shaped steel and be arranged in parallel, and described crossbeam is connected on cement mixing pile.
Between two long limits of foundation ditch, be provided with at least one group to support arrangement, to support arrangement, between two adjacent groups fish belly sill device, every group includes two Eight characters supports and is connected to two one group of struts between Eight characters support support arrangement.
The support of the described Eight characters includes two the second angle brace seats 22, a gusseted seat 24 and connects two groups of struts of two the second angle brace seats and gusseted seat; Two described the second angle brace seats are bolted the enclosing between purlin shaped steel of installation site, and the second angle brace seat is connected with capping beam by rebar connector.
Described gusseted seat is isosceles right triangle, each right-angle side of gusseted seat is connected with respectively three struts, three strut other ends are connected with a reinforcement H shaped steel 15, the position of corresponding three struts of reinforcement H shaped steel opposite side is connected with three and regulates H shaped steel 16, regulates the H shaped steel other end to be connected with the H shaped steel j223 of the second angle brace seat right-angle side; Between three struts of every group, be connected with three and connect cover plate 12; Described gusseted seat right angle vertex position is connected with one perpendicular to the strut that encloses purlin shaped steel, and the strut other end connects a jack 30, and the purlin shaped steel that encloses between jack and two the second angle brace seats is connected.
Between the gusseted seat of both sides Eight characters support, connect by four struts; Four strut supported underneath have the crossbeam vertical with strut, and crossbeam two ends are connected to two cement mixing pile tops, between two cement mixing piles, are connected with bridging 42.
When construction, adopt SMW engineering method moulding cement mixing piling wall, and build capping beam, install subsequently enclose purlin shaped steel, angle brace, to support arrangement and fish belly sill device, determine the prestressing force size of each jack and steel strand according to the concrete condition of foundation ditch, then can carry out the excavation of foundation ditch, after foundation pit construction, the parts of supporting and protection structure can be removed, taxonomic revision is in order to reusing.