Directed against the deviation in the process of fiber weighing,the structure and the working principle of the fiber feeding machine were analyzed,and the nonlinear correction mathematical model was established by getting the fiber weighing data based on LabVIEW and using the regression analysis and least square method. The fitting coefficients were sent to the programmable logic controller ( PLC ) weighing control module by LabVIEW,and the real-time automatic correction of the weighing process was realized. The correction weighing system was verified based on static load test and the stone mastic asphalt(SMA) mixture pavement performance test. Results show that after using the control model,the fiber weight deviation fells to 1. 4% from 7. 3% before correction and reaches the plus or minus 2% error design requirements. The volume of air voids ( VV ) of SMA mixture is reduced by 17%, the rut deformation is reduced,the dynamic stability increased by 4. 4%,and the flexural strength and flexural failure stiffness modulus increased by 7% and 10% respectively after correction. Other pavement performance is improved than those before correction and is the same as the performance of the laboratory test under the optimum fiber content. It provides certain help for avoiding the phenomenon with less or more fiber stabilizer in the SMA mixture and improving the SMA mixture quality.%针对纤维投料机在纤维称量过程中偏差过大的现象,在分析纤维投料机结构与工作原理的基础上,基于LabVIEW对纤维称量过程的数据采集,利用回归分析及最小二乘拟合原理,建立了纤维投料机质量称量过程非线性校正数学模型,并利用 LabVIEW 上位机系统将拟合系数实时反馈至可编程逻辑控制器( programmable logic controller,PLC)的质量称量控制模块,实现了对质量称量过程的实时自动校正.通过静态加载试验及沥青玛蹄脂碎石( stone mastic asphalt,SMA)混合料的路用性能试验对校正后的质量称量系统进行了验证.结果表明：采用该控制方式后,纤维质量称量偏差由校正前的7.3%下降至1.4%,达到了±2%的误差设计要求.校正后生产的SMA混合料空隙率降低了17%,车辙变形量减少,动稳定度提高了4.4%,抗弯拉强度与弯曲破坏劲度模量分别提高了7%和10%,且其他路用性能指标均比校正前有所提高,并与室内试验最佳纤维掺量下的性能相吻合,为避免纤维少投或多投现象的发生及提高SMA混合料的质量提供了一定的帮助.
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