Assembly And Features Of Bailey Bridge

The assembly of Bailey beam main bridge: the assembly of the single-row single-story main bridge is basically the same as that of the guide beam, the difference is that a beam is installed behind the front vertical rod of the first truss, in front of the middle vertical rod, and in front of the rear vertical rod. Then install a cross beam in front of the vertical rod and the rear vertical rod of each truss section. Each section of the truss is provided with 1 anti-wind tie rod, and diagonal braces are provided on the end vertical rod beams. The assembly procedure of the double-row single-story bridge, the first section is slightly different from the other sections. During the push-out process of the bridge, due to the deflection of the guide beam itself and the fact that the opposite bank is higher than the push-out bank, the guide beam is lower than the opposite bank and cannot be caught by the rock. The Bailey beam must install the lower chord joint at the appropriate position of the lower chord of the guide beam and connect it with a pin , so that the front end of the guide beam is tilted to obtain a certain height to ensure smooth ride on the opposite bank. At the front end where the bottom chord joints are installed, at most 4 guide beams can be installed. If the requirements cannot be met, the number of bottom chord joints can be increased. After the rollers are set, the truss can be assembled on the roll-out bank. Usually, the guide beam is assembled first, and then the main bridge is assembled.

Assembly of Bailey beam guide beam: Assemble according to the determined number of guide beam sections. The guide beam is generally not provided with a reinforcing chord, and a beam is placed behind the vertical rod at the front end of each truss. When the span length of the bridge is less than 30 meters, install diagonal braces on the beams of odd-numbered sections (1, 3, 5...), and install wind-resistant tie rods on even-numbered sections (2, 4, 6...); when the bridge spans When the diameter is more than 30 meters, each guide beam should be equipped with diagonal braces and wind-resistant tie rods. The guide beams of multi-row trusses must be equipped with support frames and connecting plates. Vertical truss: 1 and 2 groups of trusses each lift a piece of truss to align and vertically on the push-out bank rock, the direction of the male and female heads of the truss should be the same. Since the rollers are 6 meters apart and the truss is only 3 meters long, one end of the truss is placed on the rock and the other end on the temporary skid.

(1) Beam setting of Bailey beam: The beam group is placed on the beam pad behind the vertical rod at the front end of the truss, and the bolt is inserted into the innermost concave hole at the bottom of the beam, clamped with the beam clamp, but not tightened. Tighten the diagonal brace on the beam after it is installed.

(2) Assemble the second section of truss with Bailey beam: 1 and 2 groups of trusses are assembled to the second section of truss, and the connecting group is equipped with diagonal bracing on the beam of the previous section of truss.

(3) A second beam is set on the Bailey beam: the beam group is set with a beam behind the vertical rod at the front end of the second truss, clamped with a beam clamp, and then tightened after the diagonal braces on the beam are installed.

(4) Assembling the third section truss of Bailey beam: 1 and 2 groups of trusses assemble the third section truss, and the connecting group is equipped with wind-resistant tie rods in the first section truss (bridges with a span of less than 30 meters may not be installed). Two-section trusses are equipped with diagonal braces (bridges with a span of less than 30 meters may not be installed).

(5) Assembling the lower chord joint of Bailey beam: According to the predetermined number and position of the lower chord joint, assemble the lower chord joint at the two truss joints of the lower chord of the guide beam, and connect them with pins. In the future, the assembly of each section shall be carried out in a circular manner according to the above procedure, until the assembly of the guide beam is completed, the guide beam shall be ensured to be stable, attention shall be paid to coordination, and the following points shall be mastered.

①Installation of the wind-resistant tie rods of the former truss must be carried out after the beams and diagonal braces of the latter section are installed, so as to prevent lateral displacement of the truss and make it difficult to install the beams and diagonal braces.

②When installing the connecting components, the diagonal braces and wind-resistant tie rods of the previous section can be installed in place first, but not tightened. After the beams of the next section are installed, they are all tightened and fixed.

③The wind-resistant tie rod must reach the correct length and be tightened to ensure the straightness and push-out direction of the bridge.