负压检测下隧道防水板焊疤密实性检测标准试验研究

Research on the Standard Test of Tunnel Waterproof Plate Welding Scar Density Detection under Negative Pressure Detection

为探究负压检测方式下隧道防水板焊疤密实性检测中吸附压力、吸附时间和气压损失率等标准值的取值,通过开展隧道防水板焊疤吸附室内模型试验,探究了在一定吸附时间内气压损失与吸附压力、吸附面积、防水板厚度以及吸附位置等因素间的关系,并基于检测数据的稳定性、敏感性以及检测过程的时效性等需求性质,讨论分析了负压检测方式下焊疤检测标准。结果表明:各工况下气压损失数据的稳定性与吸附压力成正比,而气压损失数据的敏感性随着吸附压力的增大而减小;综合考虑检测数据的稳定性和敏感性,选择-40 kPa作为标准吸附压力值;检测数据的时效性通过单次检测的时间成本和多次检测的差异成本所确定,最终选择15 min作为标准吸附时间;通过标准吸附压力和标准吸附时间所划分的工况中最大的气压损失率,确定4%作为标准吸附损失率。研究成果可为我国隧道防水工程设计质量的提高和相应规范的修订提供必要的基础数据和科学依据。

In order to explore the values of the adsorption pressure, adsorption time and air pressure loss rate of tunnel waterproof plate welding scar compactness detection under the negative pressure detection method, the relationship between the air pressure loss and the adsorption pressure, adsorption area, thickness and adsorption location of the tunnel waterproof plate welding scar in a certain adsorption time is studied by carrying out the indoor model experiment of tunnel waterproof plate welding scar, and based on the stability, sensitivity and timeliness of the detection process of the detection data, the welding scar detection standard under the negative pressure detection method is discussed and analyzed. The results show that the stability of the air pressure loss data under various working conditions is proportional to the adsorption pressure, and the sensitivity of the air pressure loss data decreases with the increase of the adsorption pressure;considering the stability and sensitivity of the detection data,-40 kPa is selected as the standard adsorption pressure value;the timeliness of the detection data is determined by the time cost of a single test and the difference cost of multiple tests, and finally 15 min is selected as the standard adsorption time;the maximum air pressure loss rate in the working conditions divided by standard adsorption pressure and standard adsorption time is determined as 4% as the standard adsorption loss rate. The research results can provide the necessary basic data and scientific basis for the improvement of the design quality of tunnel waterproofing projects in China and the revision of corresponding specifications.