Since the reform and opening up, China's urbanization process has advanced rapidly, and the pace of construction in various places has been accelerating, which has directly promoted the continuous expansion of the scale of construction. This development momentum poses a great challenge to the traditional methods of laying and renovating excavated underground drainage pipelines, which can no longer meet the needs of reality. Therefore, there is an urgent need for more efficient and practical methods to improve construction efficiency. Trenchless pipeline detection technology has become a high-profile solution due to its unique technical advantages, and it is extremely necessary to conduct in-depth research on its application.
Commonly used detection methods
1.Electromagnetic method
The electromagnetic method excels in terms of detection accuracy and efficiency. The principle of electromagnetic induction is used to detect underground metal pipes and cables, although the effect on non-metallic pipes is not obvious, but in most cases, the detection work can be completed by electromagnetic method. This method converts and applies signals at different frequencies to propagate the signals of underground pipelines to the control center. At present, this method is widely used in the detection of underground pipes in many cities, especially for water supply and drainage pipes.
Crews are entering the pipeline to probe.
2.Electromagnetic wave (geological radar) method
Geological radar detection uses the principle of electromagnetic wave reflection to detect underground targets according to the electromagnetic differences between underground targets and the surrounding medium. Geological radar plays a key role in non-metallic pipes made of special materials, such as cement, plastic, PVC, and other non-metallic pipes. By observing the trend, amplitude and waveform data of the radar reflected echoes reflected back, the structure of the underground medium can be inferred.
Crews are entering the pipeline to probe.
Engineering example of trenchless pipeline detection technology
1.Project Overview
In a CIPP repair project of a sewage pipeline, the original pipe is PVC pipe diameter 300mm or concrete pipe diameter 450mm. Detailed inspections revealed problems such as water leaks, disjoints, and cracks. In order to restore the function of the pipeline, a thorough rectification plan is proposed.
2.Construction process
Dip with suitable resin.
Wrap the felt slip around the airbag and enter the site to be repaired.
Aeration, steam or water solidify the felt tube and patch.
The airbag is narrowed and the tubing is pulled out, and finally it is inspected and quality checked.
3.Probing method
Tracer method:Use an underground pipeline detector with a tracer to scan the received signal for positioning and depth fixation.
Guide Detection Method:Contains receivers and sensors for pipe positioning and depth measurement by means of a pipe threading device.
Inertial (gyrographic) positioning method:The law of inertia and the law of conservation of angular momentum are adopted, and the three-dimensional coordinates of the pipeline are recorded without electromagnetic interference.
Conclusion
Trenchless pipeline detection technology is an advanced, widely applicable and economically beneficial construction technology. At present, these methods have been widely used, providing a strong technical guarantee for the safe operation of urban underground pipelines.