Issues that should be paid attention to when installing construction guardrail nets on highways

1. The highway guardrail net should be implemented as soon as possible after the roadbed engineering of the highway guardrail net is completed; the construction unit should formulate a detailed construction structure plan before construction and submit it to the supervision engineer for approval. The contractor should carry out construction layout according to the agreed construction structure plan, the requirements of the drawings and the actual terrain and landforms, determine the construction plan of the center line of the column, and carry out the necessary site clearing and digging of tree roots in order to build the highway guardrail net according to the specified slope and line shape. 2. If there is a disconnection in the highway isolation fence or at the intersection of the road, the column spacing can be adjusted appropriately as needed. When crossing the river, if the width of both sides of the river is not more than 6M, they should be connected as shown in the drawings or with barbed wire; when the width of both sides of the river is greater than 6M, the highway guardrail net should be closed and connected.
III. When the construction planning unit requires that the posts, supports or anchors of the guardrail net be buried in the concrete foundation in the drawings, the contractor should set up the necessary temporary cables or supports to fix the posts in place until the concrete softens. During the 7D period of concrete health preservation, no materials or components should be placed or tightened on the posts, cables and supports. All posts shall be buried vertically in accordance with the requirements and line shape of the drawings
Fourth, where the high-voltage transmission line passes through the highway guardrail net, the highway guardrail net shall be connected to the ground wire according to the provisions of the power department
Five, when the wire is parallel or nearly parallel to the highway guardrail net and the wire is above the highway guardrail net, the ground wire shall be buried at each end or at a spacing of no more than 400M, and the grounding resistance value shall be less than 10Ω (ohm)
Six, the burial of the posts shall be carried out in sections, first bury the posts at both ends, and then pull the wire to bury the central post. From the longitudinal point of view, the axis of the post shall be in a straight line, and no uneven phenomenon shall be shown; from the height point of view, the top of the post shall be smooth, and no uneven situation shall be shown
Seven, the mesh of the highway guardrail net that meets the requirements of the size and model shall be firmly installed from the end of the post to the hook of the post according to the method specified in the drawing; or the mesh shall be installed in the frame, and the connection between the frame and the post shall be firm All meshes and wires should be taut without deformation, and their installation height should be in accordance with the drawings. After the installation of the isolation fence is completed, the foundation of the column needs to be compacted.
Eighth, it should be installed as shown in the drawings and placed firmly on the column or support; the metal mesh should be stretched and tightened, and the entire structure should not be distorted.
Ninth, when constructing the guardrail net, it should generally be installed along the terrain. When necessary, geotechnical leveling is required to obtain a uniform surface. In concave areas, when the local longitudinal profile changes gradually and the specified clearance height from the ground cannot be maintained, longer columns can be used, and then multiple strands of barbed wire can be pulled. The vertical clearance between the barbed wires is equal to or less than 150MM. After excavation or drilling, all columns should be buried according to the agreed method. Generally, diagonal braces should be added on both sides of the column every 120M to ensure its stability; if the highway guardrail net changes direction according to construction requirements, the column should be equipped with three-way diagonal braces.