Expansion joint construction method

1. Make preparations before construction

Before the official start of construction, while ensuring that the municipal road and bridge project obtains the relevant construction permit, it is also necessary to do a good job in the construction report to ensure that the project construction has complete conditions for starting. The construction plan should be formulated according to the relevant engineering requirements, provide effective reference for on-site construction, and guide the orderly progress of on-site construction. A sub-analysis of the previous construction management can find that in the process of construction, there is a construction theme that fails to face up to the importance of the construction plan designation, and there are certain application problems, which lays down quality hazards for the smooth progress of the project construction. In the process of designing the construction plan, it is necessary to combine the construction conditions with the actual situation of the construction site to ensure the scientificity and rationality of the construction plan. At the same time, it is also necessary to pay attention to the quality control work, and before the start of construction, it is necessary to clarify the responsibilities of all parties, and implement the on-site construction responsibility system, and make important work arrangements. After having an in-depth understanding of the project, it is necessary to formulate the construction plan, comprehensively consider all factors, and clarify the construction ideas to ensure the smooth progress of the construction road project and bridge design. At the same time, the construction unit also needs to formulate relevant technical standards and specifications, formulate a management system with implementation rules, investigate hidden dangers in a timely manner, scientifically standardize the behavior of construction personnel, and improve the sense of responsibility of project management personnel and construction personnel.

2.Expansion joint cutting construction

Before carrying out expansion joint cutting construction, it is necessary to understand the related factors of expansion joints, the quality of expansion joints is related to the flatness of the road, and in the process of enlarging the cutting surface, it is also necessary to consider the actual flatness. After the cutting surface is enlarged, the flatness of the pavement must be rent-free The specific construction requirements of the expansion joint, once there is a deviation problem, it is necessary to do a good job of rework and handling before the construction of the expansion joint, and measure the flatness. After verification to ensure that there is no problem with the flatness, the cutting construction can be carried out, and the width of the groove needs to be confirmed before construction, and the construction should be carried out in strict accordance with the requirements of the drawing. In order to reduce the pollution of stone powder to the pavement during the cutting process, it is necessary to protect the pavement purposefully, generally you can place cloth strips, steel plates on the pavement before cutting, or protect the pavement by taping tape or covering plastic sheeting. In addition, it is also necessary to ensure that the cutting seams on the surface of municipal roads and bridges are straight and pollution-free, and the cutting process should be carried out in strict accordance with relevant requirements to ensure that the cutting joints are straight and neat, and the quality requirements of the engineering surface should be met. At the same time, in order to control the pollution problem of the road surface, it is also necessary to do a good job of timely cleaning after the end of the cutting seam, which can be rinsed with clean water to ensure the cleanliness of the reservoir surface. If no water is added during the expansion joint cutting process, the dust can be cleaned up by a blower after the cutting seam is completed, reducing the difficulty of subsequent cleaning. In the process of cutting, it is also necessary to control other factors, comprehensively consider the process requirements of expansion joints, and once problems arise, they need to be solved in time to ensure the cutting quality of expansion joints.

3.Expansion joint grooving construction

In the process of grooving expansion joints of municipal road and bridge projects, the depth of the groove should usually be controlled above 13cm. In the process of grooving the expansion joint, it is first necessary to use a wind pick to clean up the debris and garbage in the groove to ensure the cleanliness of the construction site. Secondly, after the end of the grooving, it is also necessary to carry out the installation of the section steel, before the installation of the embedded reinforcement in the expansion joint groove to carefully check the condition, if there is damage, it is necessary to replace it in time, if there is a problem of rust and deformation, it is necessary to carry out timely rust removal and straightening to avoid affecting the actual function of the expansion joint. The state before and after the expansion joint is grooved is mainly shown in Figure 1, so after the expansion joint is grooved, the relevant construction personnel need to set warning signs in the corresponding area to reduce the impact of vehicles and human factors on the construction quality of expansion joint concrete.

4.Expansion joint installation and construction

In the process of municipal road and bridge construction, the installation link of expansion joints is particularly important, and the main installation diagram As shown in Figure 2, its width needs to be controlled within 2mm, and the center line of the expansion joint should be consistent with the center line of the beam end. After placing the expansion joint in the notch, the construction personnel need to fine-tune it to ensure that its elevation meets the design standard specifications, and at the same time make use of reinforcement measures to set the welding joints reasonably. The determination of the position of the solder joint needs to abide by the principle of symmetry on both sides to reduce the probability of expansion joint displacement. When retesting the elevation, the deformation and displacement of the expansion joint should be controlled within a reasonable range. In the process of welding, the relevant construction personnel need to reinforce the embedded steel bars and the anchor steel bars of the section steel from both sides, and ensure that the distance between the welding joint and the section steel is maintained within 5cm. Finally, after the welding is completed, it is necessary to check the installation position of the expansion joint to ensure that its installation position can meet the relevant design requirements.

5. Concrete pouring and maintenance

Before concrete pouring, the slurry groove should be cleaned to cover the concrete pavement on both sides to avoid concrete pollution to the pavement or flow into the joint and control box during the construction process. In the process of concrete pouring, it is necessary to ensure that the upper and lower structures are completely connected with the bearings, and to ensure that the poured structure can expand and contract naturally under the action of ambient temperature. In the process of pouring concrete, it is not only necessary to control the amount of admixtures, but also to do a good job in slump testing. After the pouring is completed, it is necessary to carry out post-maintenance work, sprinkle water on the surface after the concrete initially sets, and use cotton felt cloth to cover it to ensure that the concrete construction remains wet. Finally, it is necessary to do a good job in controlling the temperature difference between inside and outside, and strictly prohibit the entry and exit of vehicles and personnel.