Waveform guardrail installation method

Release time:

2016-11-13


A guardrail plate construction programme, construction methods:

1. Waveform guardrail plate construction

Waveform beam steel guardrail is to prevent uncontrolled vehicles over the central divider or in the road side of the more dangerous sections of the roadbed, without secondary accidents; in order to absorb energy, reduce the degree of accidents and damage to vehicles and personnel and induced line of sight and beautification of the road.

(1), the construction programme ① strictly in accordance with the requirements of the bidding documents to purchase materials, all steel according to the requirements of the bidding documents must have material quality certification. Corrugated beam steel guardrail steel components used are hot dip galvanised metal anti-corrosion treatment, high strength bolts for hot dip galvanised high strength bolts connected surface to be coated with grease, and phosphate lubrication treatment, in the factory should be sealed packaging, in order to prevent rust or dirt during transportation, preservation. ② the total construction sequence for the first single-sided guardrail after the double-sided guardrail, the last anti-glare facilities installed, using segmental construction, section by section connection, according to the section of the self-inspection, the implementation of the whole process of quality control, to ensure that the whole line of high-quality completion. ③Construction team set up piling team two groups, installation team two groups, measurement team one group, maintenance team one group, transport team one group, a total of 15 people. It is proposed to equip 2 sets of DY300 piling machine, 2 sets of AC welding machine and 1 load car.

(2), waveform guardrail plate construction method a column installation

(a) Adopt driving method to set up columns. Punching method to set up columns, should be strictly in accordance with the position of the steel brazier, the first place to place the homemade guide, and then the column along the guide hole to ensure the verticality. Columns should be driven into the soil to the design depth, when driven too deep, the columns should not be partially pulled out to correct, but must be pulled out, wait until the foundation is compacted and re-driven. Column installation should be consistent with the design drawings. And with the road line shape coordination, columns should be firmly buried in the soil, to the design depth, and perpendicular to the road surface.

(b) If it is difficult to drive in, the column can be installed by drilling method or excavation method. When the column installation is carried out by the boring method, the column shall be backfilled with the same material as the road base after positioning and compacted by tamping in layers so as to have a compactness not less than that of the adjacent in-situ soil. When the excavation method is used for construction and the columns are buried, the backfill shall be made of good and identical materials and tamped in layers (each layer shall not be more than 15cm thick), and the compaction of the backfill shall not be less than that of the adjacent in-situ soil. Post piles in rock should be backfilled with granular material and tamped.

(c) Considering the impact of the guardrail structure on the landscape and the sight-inducing influence of drivers, the verticality, position and elevation shall be checked immediately after the columns are installed in position. Verticality checking adopts leaning rule to check root by root. Position check, spacing check straight line using a steel ruler test, curve section using off-angle method using a latitude and longitude detection; lateral position check using a ruler to measure the road centre line and column lateral spacing. Elevation check, to the inside of the kerbstone road surface as a reference, using self-made mould or level meter check one by one. Its horizontal and vertical directions should form a smooth line. Installation of gradient section and end columns is the part to be paid attention to during construction, and the column position, height and parabolic shape should be strictly controlled during construction. b anti-block, waveform beams, end of the installation

(a) After adjusting the column, you can install the bracket (block). The bracket (block) is fixed between the waveform beam and the column through the connecting bolt. Before tightening the connecting bolts, the bracket (block) should be adjusted so that it is accurately seated.

(b) Waveform beams are spliced with each other through splicing bolts and fixed to the bracket (block) by connecting bolts. The lap direction of the roadbed guardrail and waveform beam is the key to installation, which is carried out in strict accordance with the drawings. Lap direction should be consistent with the direction of travel. Waveform beams should be continuously adjusted during installation. Therefore, its connecting bolts and splicing bolts should not be tightened prematurely so that the long round holes of the waveform beams can be used to make timely adjustments during the installation process, so as to form a smooth line and avoid local concavities and convexities. When the line shape of the guardrail is considered satisfactory, the bolts can be tightened at last. The connecting bolts between the bracket (anti-block) and the waveform beam should not be tightened too much, so as to use the long round hole to adjust the temperature stress.

(c) The end beams are spliced with the standard section guardrail through the splicing bolts. The construction method of end beam is basically the same as that of waveform beam. After the construction is completed in sections, self-check and report to the supervising engineer for acceptance.

Waveform guardrail plate in the installation of precautions:

(1) the column shall not have obvious twist, no welding lengthening, end burrs must be removed. Column sampling should be based on the control points on the highway, according to the amount of distance between the column spacing for appropriate adjustments; column installation should be consistent with the design drawings, and coordinated with the road line; columns must be firmly buried in the soil, and the depth of burial must be designed to reach the specified depth, and perpendicular to the ground plane.

(2) Regardless of the method of installing the guardrail, the contractor should try to avoid damaging the pipeline facilities buried under the road surface, if the damage is caused by the contractor shall be responsible for repairing the damaged repair costs borne by the contractor.

(3) After the guardrail is installed, the horizontal and vertical directions should form a smooth line. It should have a good induction of landscape and driver's sight.

(4) The waveform beam guardrail set on the road side should not allow the guardrail surface to intrude within the highway construction boundary.

(5) The waveform beam plate should generally be formed by continuous roll forming. The bolt holes on the waveform beam must be accurately positioned, and all the spliced bolt holes at each end section should be punched at one time.

(6) During the period from the completion of installation of column to the installation of column cap, the column should be prevented from dropping debris.

(7) The connecting bolts and splices of waveform beams should not be tightened too early.

(8) Before tightening the connecting bolts, the bracket (anti-resistance block) should be adjusted to be accurately in place.

(9) Guardrail, end, column length and width direction does not allow welding, members should not have cracks.

(10) Anti-block shall not have obvious torsion. End cuts should be straight and burrs must be removed. The weld shall be smooth and even, and the weld position shall be located on any plane without screw holes.

(11) The end shall not be obviously twisted. The cut shall be vertical and the end burr must be removed. The curved part shall be rounded and smooth.