The Development And Application Of Bridge Pre-stressed Duct Grouting Quality Detector

In bridge engineering, grouting pre-stressed duct is regarded as a covert project. Grouting quality depends on the level of construction technology and construction management. Actually, pre-stressed ducts are not dense or completely empty, which is a common phenomenon. They are difficult to meet the design requirements. Recent years, it is common that bridge collapse, caused by pre-stress disappearing, results in serious engineering accidents and great economic loss. Advantage of pre-stressed system is based on the foundation that tendons and concrete are intact. Grouting quality of the pre-stressed pipe affects the security, reliability and service life of the pre-stressed structures directly. So it is necessary to detect the grouting quality of pre-stressed duct, exclude security risks and ensure that construction quality meets the design requirements.At present, there is no systematic and perfect technology for the pre-stressed ducts grouting quality detection at home and abroad. Referring to engineering quality nondestructive testing requirements, it is of great importance to do the research of bridge pre-stressed duct grouting quality testing technology. This article is aimed at an entire research of bridge pre-stressed duct grouting quality detection technology, which relies on the scientific research project of Yunnan aerospace engineering geophysical detecting company limited. The following are the mainly achieved results of the technology research work:1、Through a large number of related literature at home and abroad, this paper are summarizing for the development status of the pre-stressed ducts grouting quality detection, and as a reference, it tries to explore a new idea of accurate and efficient quality detection of the pre-stressed ducts grouting, and combining with the actual demand for bridge detection, the paper verifies the feasibility of the new idea.2、Based on the elastic wave theory, this paper mainly expounds the pre-stressed ducts grouting quality detection, and on the basis of the existing detection technology, it has carried on the further theoretical derivation for related theory of the pre-stressed ducts grouting defect location technology.3、The paper first makes a research into the source and the signal of the pre-stressed ducts grouting quality detection of bridge, and makes a mathematical statistics on wave velocity, energy attenuation and frequency shift eigenvalues of different plumpness pipeline response under the specific source signal. 4、Basing on Wi-Fi wireless transmission technology, a set of the pre-stressed ducts grouting quality detector of bridge has been developed. With controllable magnetic source and the professional pre-stressed ducts grouting quality detection signal acquisition and analysis software, the detector has functions of rapid grouting plumpness level intelligent evaluation and grouting defect location so that accuracy and stability of the detector are verified by model validation test.5、Referencing to local standards of bridge test in Yunnan province, a set of process of efficient professional pre-stressed ducts grouting quality detection is established. By the project application, the applicability and efficiency of the complete set of bridge pre-stressed ducts grouting quality detection technology are recognized by the owner and the third party testing unit.