基于变异函数模型的钢桥面防腐层施工质量评价

Construction quality evaluation of anticorrosive coating on steel bridge deck based on variogram model

为评价钢桥面防腐层施工质量,针对车载抛丸设备、手推式抛丸机、人工打磨除锈工艺随机选择6组10 cm×10 cm区域检测粗糙度,分析了3种除锈工艺粗糙度指标的数学特征与施工质量的变异性;针对全断面机械喷涂与人工滚涂工艺,分别检测车载抛丸设备除锈后的桥面板基面喷涂面上覆盖16 m×27 m区域共9×10个点的漆膜厚度,基于变异函数模型研究了2种喷涂工艺的变异特征,通过球状模型拟合得到变程、块金值、基台值等参数,从横向与纵向着重分析了机械喷涂面漆膜厚度的空间分布规律。结果表明,车载抛丸设备施工的粗糙度检测数据全部合格,手推式抛丸施工的粗糙度检测合格率为93.3%,人工打磨的粗糙度合格率仅为66.7%;车载抛丸设备施工的粗糙度变异系数值都稳定在平均值附近,其施工波动性最小;全断面机械喷涂施工的基台值为307.95、365.39,小于人工滚涂的540.89、373.42,机械喷涂工艺的总变异性小于人工滚涂;机械喷涂面漆膜厚度的分布具有各向异性。建议在钢桥面防腐层施工中增大车载抛丸设备与全断面机械喷涂设备的使用比例,尤其注意搭接处抛丸与喷涂质量的控制。

In order to evaluate the construction quality of anti-corrosion coating on steel bridge deck,three kinds of rust removal technologies and two kinds of spraying technologies were investigated.Six groups of 10 cm×10 cm area were randomly selected to detect the roughness of vehicle mounted shot blasting equipment,handpropelled shot blasting machine and manual grinding and derusting technology,and the mathematical characteristics and construction quality variability of the three rust removal technologies roughness indexes were analyzed.Aiming at the full section mechanical spraying and manual rolling coating process,the base surface of the bridge panel after rust removal by vehicle shot blasting equipment was selected to detect the paint film thickness of 9×10 points covering 16 m×27 m area on the spraying surface,respectively.Based on the variogram model,the variation characteristics of the two spraying technologies were studied.The parameters such as range,nugget value and base value were obtained by spherical model fitting.The spatial distribution rules of the coating film thickness of mechanical spraying were analyzed from the horizontal and vertical directions.The results show that the roughness test data of vehicle mounted shot blasting equipment are all qualified,the qualified rate of manual shot blasting is 93.3%,and that of manual grinding is only 66.7%;the roughness variation coefficient values of vehicle mounted shot blasting equipment construction are stable around the average value,and the construction fluctuation is the minimum.The base values of full section mechanical spraying construction are 307.95 and 365.39,which are smaller than 540.89 and 373.42 of manual rolling coating.The total variability of mechanical spraying process is less than that of manual roll coating,and the film thickness distribution of mechanical spraying is anisotropic.It is suggested that in the construction of anticorrosion coating on steel bridge deck,the proportion of vehicle mounted shot blasting equipment and fullsection mechanical spraying equipment should be increased,especially pay attention to the quality control of shot blasting and spraying at the lap joint.