Total Weight and Axle Loads of Truck Units in the Transport of Timber Depending on the Timber Cargo

Abstract

When transporting timber, the high variability of species, assortments and moisture content of the wood raw material does not allow the weight of the transported timber to be precisely determined. This often contributes to the excessive weight loading of the entire truck unit. The aim of the research is to present the variability of the total weight of truck units with wood cargoes (GVW-gross vehicle weight) depending on the weight of the empty unit and the transported timber load, as well as to analyze the changes in GVW, unit loads of wood and load on individual truck unit axles depending on the season. This study analyzes the total weight of truck units for 376 transports of Scots pine timber at different times of the year. The total weight of the truck units depends on the weight of an empty unit and the weight of the load. GVW was determined by using a weighbridge to weigh the vehicles and then the empty unit after unloading. The weight of the load was obtained as the difference between GVW and the tare. It was found that GVW differed significantly depending on the truck unit used, ranging from 43.60-58.80 Mg, often exceeding permissible limits for public roads. The individual axle loads for various truck units were also analyzed. The obtained results indicate that these loads are more equally distributed in the case of five-axle trucks compared to six-axle ones.

Multi-Factorial Load Analysis of Pine Sawlogs in Transport to Sawmill

“…Our study shows that, currently, the volume of the wood is similar in the entire analyzed period (no statistically significant differences) and does not depend on season of the year or origin of the wood. The lack of statistically significant differences in load volume when analyzing transports using semi-trailer trucks was demonstrated by Trzciński and others [12], at the same time indicating significant differences (however of little practical significance) between the results from autumn and the remaining seasons of the year for vehicle units with a trailer. The load volume slightly differed for transports in the autumn and summer [30].…”

“…Analyses of timber transport research, omitting studies on the forest biomass supply chain (sawdust, wood shavings, wood chips, etc. ), concerns actual data specific to a given region [11,12,16,18,19,21,26,[28][29][30], tree species and their origin, the assortments of transported timber [12,13,22,[25][26][27][28], the types of transport used [10][11][12]15,16,19,21] or legal regulations (total permissible mass of the DCM unit) and costs [3,7,8,12,13,[16][17][18]20,34,38]. A good diagnosis of the configuration of timber truck units, their own mass and their potential timber cargoes, given the large variation in cargo weight, can contribute to improving the efficiency of forest transport [16,14].…”

“…Based on the literature [11,12,26], we know that the volume and mass of loads in the transport of freshly felled wood differs, therefore the mass of one cubic meter of the load, calculated as the quotient of the load mass (kg) and its volume (m 3 ), was used for the comparative analyses of the effect of timber origin.…”

“…Differences also occur between single pairs of months: March and June as well as June with January and March (Figure 2d). The literature contains analyses of timber transports by season [12,29,30]. We analyzed changes in the values of the characteristics of timber loads depending on the season.…”

“…These include vehicle load capacity, driving time and fuel consumption [10,11]. It is estimated that the share of costs of timber transport in the total cost of wood processing is about 17% [12]. Transporting timber is the most expensive process of obtaining the raw material and may constitute 40%-60% of the total cost of its harvesting [13].…”