A Robust Productivity Model for Grapple Yarding in Fast-Growing Tree Plantations

作者：Engelbrecht Riaan; McEwan Andrew; Spinelli Raffaele^*

来源：Forests, 2017, 8(10): 396.

DOI：10.3390/f8100396

• productivity
• logging
• steep terrain
• cable logging
• Acacia mangium

New techniques have recently appeared that can extend the advantages of grapple yarding to fast-growing plantations. The most promising technique consists of an excavator-base un-guyed yarder equipped with new radio-controlled grapple carriages, fed by another excavator stationed on the cut-over. This system is very productive, avoids in-stand traffic, and removes operators from positions of high risk. This paper presents the results of a long-term study conducted on 12 different teams equipped with the new technology, operating in the fast-growing black wattle (Acacia mangium Willd) plantations of Sarawak, Malaysia. Data were collected continuously for almost 8 months and represented 555 shifts, or over 55,000 cycleseach recorded individually. Production, utilization, and machine availability were estimated, respectively at: 63 m(3) per productive machine hour (excluding all delays), 63% and 93%. Regression analysis of experimental data yielded a strong productivity forecast model that was highly significant, accounted for 50% of the total variability in the dataset and was validated with a non-significant error estimated at less than 1%. The figures reported in this study are especially robust, because they were obtained from a long-term study that covered multiple teams and accumulated an exceptionally large number of observations.

• 出版日期2017-10