基于压电原理的装配式结构套筒灌浆饱满度检测方法研究

Research on the testing method for grouting plumpness of prefabricated structural sleeve based on piezoelectric principle

为解决当前装配式结构套筒灌浆饱满度检测成本高、难以实时检测的技术难点,开发了基于压电测试原理的检测方法及设备,开展了相关的材料试验、模型测试和工程应用研究。首先,通过灌浆料的电学特性测试,探究灌浆料类型和凝固时间对压电测试结果的影响;然后,通过透明套筒的灌浆-漏浆循环试验,分析压电法对漏浆缺陷测试的有效性;进一步,通过预制模型试验,确定压电法判定灌浆饱满度的阈值;最后,依托广州东晓南路—广州南站连接线装配式桥梁工程,验证了压电法用于测试灌浆饱满度的有效性和实用性。研究结果表明:在埋没于灌浆料后,压电传感器测得的谐振电压显著降低,且该电压值在60 min内总体保持平稳,之后随着凝固时间的增加,电压值增长,且逐渐接近试验前初始电压值。在灌浆-漏浆循环试验中,无论传感器采用平放还是竖放的埋设方式,谐振电压均呈现出较明显的变化,说明压电法受传感器埋设方式的影响较小。对于套筒内灌浆饱满情况,其测量电压与灌浆前初始电压之比小于0.4,此数值可作为灌浆饱满度的判定阈值。工程应用结果表明,压电法现场操作方便,可指导现场对灌浆缺陷套筒进行补浆,满足对装配式结构套筒灌浆过程中的质量控制要求。研究结果为解决套筒灌浆质量检测难题提供了一种新途径和实践参考。

In order to solve the technical challenges of high cost and difficulty in real-time detection of the sleeve grouting fullness in prefabricated structures,the detection method and device based on the piezoelectric testing principle were developed,and relevant material tests,model tests,and engineering applications were carried out.First,the influence of grouting material type and setting time on the piezoelectric test results was investigated by electrical properties test of grouting materials.Then,the effectiveness of the piezoelectric method for testing grout leakage defects was analyzed through the grouting-leakage cycle test of transparent sleeves.Furthermore,through prefabricated model tests,the threshold of the piezoelectric method for judging the grouting plumpness was determined.Finally,relying on the prefabricated bridge project of the connecting line between Dongxiao South Road and Guangzhou South Railway Station,the effectiveness and practicality of the piezoelectric method for testing grouting plumpness were verified.The research results show that the resonant voltage measured by the piezoelectric sensor is significantly reduced after being buried in the grouting material,and the voltage value generally remains stable within 60 minutes.Afterwards,as the setting time increases,the voltage value increases and gradually approaches the initial voltage value before the test.In the grouting-leaking cycle test,whether the sensor is laid horizontally or vertically,the resonant voltage shows obvious changes,indicating that the piezoelectric method is less affected by the sensor laying mode.For the case of full grouting in the sleeve,the ratio of the measured voltage to the initial voltage before grouting is less than 0.4,which can be used as the threshold for judging the grouting plumpness.The engineering application results indicate that the piezoelectric method is convenient for field operation,can guide on-site grouting for defective sleeves,and meet the quality control requirements during the grouting process of prefabricated structural sleeves.The research results provide a new approach and practical reference for solving the quality detection problem of sleeve grouting.