The safety construction plan of the bridge construction full hall support

Before the bracket is erected, check the bowl buckle rod in advance, and shall not use digging, bending, corrosion, etc., as well as components with damage and obvious defects, and the bowl buckle or pin must use a special pin. Bowl fasteners must be inspected one by one before entering the site to see if they meet the quality requirements and design requirements.

The bracket should be erected hole by hole, and the position of the bracket must be determined on the basis according to the construction plan drawing when erection, and then the foundation elevation is measured, and then the elevation of the vertical rod and the upper longitudinal and transverse distribution beam is determined according to the beam bottom and the foundation elevation, and then the bottom bracket is placed at the beginning, and the position of the bottom bracket is required to be accurate, and the height is adjusted to the calculated height. When the bracket is erected, the line type should be controlled to prevent local force. The proportion of stent joints in one plane does not exceed 50%.

When assembling the pole, it is necessary to check the verticality with a hanging hammer to prevent the pole from being eccentricly stressed. The joint must be firmly connected with a bowl buckle. When the bracket is assembled, the line should be hung to control the leveling and line type.

In the adjacent part of the bracket and the permanent pier platform, an annular hoop is set up with a steel pipe fastener (vertically according to the actual setting of the site), and the support pole and the pier body form a connecting wall piece to strengthen the stability of the support.

The maximum exposed part of the top bracket and the bottom bracket shall not exceed 20 cm, and the free end of the rod with a length of more than 20 cm shall be locked with a horizontal rod; The bottom bracket and the hardened ground should be closely attached to achieve the surface stress, and it is strictly forbidden to form a point stress. The length of the top support screw buckle is not more than 20 cm, the longitudinal square wood joint can not have a gap, and can not be suspended, if there is a gap, it is cross-connected with a nail cross, and the square wood is plugged tightly with a wooden wedge, and nailed with a nail. If there is a gap between the transverse steel pipes, the two steel pipes should be welded with coarse steel bars or connected with straight fasteners.

The bowl buckle bracket is cushioned with 10 375px square timber under the bottom bracket of the backfill part of the foundation pit of the cushion cap to expand the stress area and reduce the uneven settlement.

The bowl buckle bracket is strengthened with a horizontal steel pipe along the pier body in a circle, and the top of the steel pipe is provided with a jacking bracket and the pier body is closely stressed.

After the bowl buckle bracket is put together, a scissor brace is arranged every 4 rows along the vertical and horizontal direction on the fastener steel pipe with a fastener steel pipe, the scissor brace is set up from the top to the bottom to be continuous, the lap joint is guaranteed to be not less than 60 cm, the joint card is not less than two, the angle between the horizontal crossbar is 45 ° 60 °, the two scissor braces are not allowed to intersect themselves, and they are required to be arranged on both sides of the vertical rod.

In order to prevent the displacement of the diagonal brace steel pipe and the flange plate lower bracket due to the expansion of the side mold of the side web during the concrete pouring process of the cast-in-situ box girder, the cable-stayed steel pipe needs to be arranged on the flange plate support, the cable-stayed steel pipe should penetrate into the bottom plate and the lower support at least 3 standing rods, and one should be arranged every other row, and the intersecting parts of the standing rods should be connected with fasteners, and the angle with the horizontal crossbar is 30 °.

If the height of the bracket is higher than 5m, a horizontal scissor brace needs to be set, and the spacing of the horizontal scissor brace is not more than 5m.

The height of the sweeping rod of the formwork support from the ground shall be less than or equal to 875px, and the length of the upper end of the vertical rod, including the adjustable screw rod extending out of the top horizontal rod, shall not be greater than.

<> introduction of the cast-in-situ continuous box girder full hall support scheme for the main line viaduct.

Section 2 Project OverviewAs an eastward extension of the Central Ring Road, the North Passage of Pudong International Airport is an east-west expressway in the southeast of Shanghai, and is a fast passage connecting the Central Ring Road and Shanghai Pudong International Airport, with a total length. The new construction of the north passage of Pudong International Airport starts from Shenjiang Road in the west to the main approach road of Pudong International Airport in the east, and the road is divided into elevated road and surface road. Among them, the elevated charge road is designed according to the urban expressway, with 8 lanes in both directions and a design speed of 80km h, the surface road Shenjiang Road A30 is designed according to the urban trunk road design standard, and the A30 main approach road is designed according to the urban secondary trunk road design standard, all of which are two-way 6 lanes with a design speed of 50km h.

The starting and ending mileage of this section is K8+921 K9+527, the total length is 606m, and the bridge area is 18483m2. The superstructure of the main line viaduct is in the form of "butterfly type" large boom arc type prestressed concrete cast-in-situ continuous box girder, with high beams and multiple chambers in one box. mileage station (K8+921 K9+527), with a total length of 606m, and the span arrangement is:

35m+35m)＋(35m+35m)＋(35m+40m＋35m)＋(35m+40m＋40m＋35m)+(35m+35m+35m)+(35m+38m+35m)。The standard span of the prestressed concrete equal-height continuous box girder is 3 35m, the cross section adopts a single box and six chambers, the total width of the box girder structure, the bridge deck adopts a two-way 2% cross slope, the roof is thick, the bottom plate is thick, the web in the middle of the span is thick, and the end is magnified to the reed web. Set up side pier beam and middle pier beam, do not set up mid-span beam.

The beam at the top of the side pier is thick, and the beam is thick at the top of the middle pier.