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An investigation into the shorthaul transport of pulpwood in South AfricaAckerman, Pierre Alexander 12 1900 (has links)
Thesis (MScFor)--Stellenbosch University 2001. / ENGLISH ABSTRACT: Ackerman PA. 2001. An Investigation into the Shorthaul Transport of Pulpwood in
South Africa. M.Sc. in Forestry thesis. University of Stellenbosch. 178 pp
Shorthaul transport also known as secondary intermediate transport (SIT), a unique
feature of pulpwood transport in South Africa, is an additional transport phase within
traditional secondary transport. SIT originates at a roadside landing or depot and
terminates at another depot, rail siding or merchandising area (not the final destination).
The reason for the addition of SIT into the transport chain is identified as the steady
decline of forest road conditions to the extent that highway vehicles are unable to reach
roadside landings, necessitating the use of intermediate storage sites, from where the
timber is once again loaded and transported to final destination.
An industry survey established that the decline of forest road conditions are related to
excessively high road densities, insufficient funding for road maintenance/upgrading
and the lack of understanding by landowners of the importance of maintaining forest
road infrastructure. Total funding, by pulpwood companies on roads have shown an
increase of R18.55 million from 1997 to 2000, however, subsequent surveys have
indicated, that despite this increase in funding, the forest road conditions continue
deteriorating.
Of the total annual pulpwood intake of 9.39 million tonnes for 1998, 3.7 million tonnes
are subject to SIT. Of this 3.7 million tonnes, 2.5 million tonnes are transported from
stump to depot and 1.2 million tonnes are transported from landing to depot. The survey
identified the agricultural tractor and semi-trailer as the most favoured transport system
between stump or landing and depot, responsible for transporting 2.22 million tonnes
annually. For 1998, manual loading and three wheel log loaders accounted for the
loading of 0.6 and 2.1 million tonnes respectively of the 3.7 million tonnes subject to
SIT.
This survey information, assisted by newly developed terminology, was used to develop
transport scenarios for the economic analysis of total cost of the different transport
phases. A network analysis model and pixel-based geographic information system
(GIS) were combined to analyse the various transport scenarios within three study
areas in the KwaZulu/Natal Midlands, employing SIT on poor, high-density road
networks. The simple pixel-based GIS contained information on the forest road
network, surface cover and slopes.
The results of the economic analysis highlighted the need for the reduction of road
network density and for the improvement of the remaining network. This would
eliminate the need for extended primary transport and allow the use of highway vehicles
transporting from the compartment roadside to and past plantation exits. Results show
an average annual cost penalty to the industry, by maintaining SIT, to be R43.25 million
or R8.24/m3
. By not employing SIT the industry will potentially save R4.60 for every
tonne of the 9.4 million tonnes consumed by the pulpwood processing plants during
1998.
Key words: Network analysis. Pixel-based GIS. Timber transport. Secondary
transport. Secondary intermediate transport. Secondary terminal transport. Extended
primary transport. Primary transport. Dirichlet tessellations. Shorthaul.
Note: Throughout this document a full stop (.) is used as a decimal separator. / AFRIKAANSE OPSOMMING: Ackerman PA. 2001.'n Ondersoek na die kortafstand vervoer van pulphout in Suid-
Afrika. MSc in Bosbou tesis. Universiteit van Stellenbosch. 178 pp.
sekondere intermediere vervoer (SIV), 'n addisionele vervoer-fase binne tradisionele
sekondere houtvervoer, is 'n unieke kenmerk van pulphout vervoer in Suid-Afrika. SIV
begin op pad, by 'n spesifieke vak of depot en eindig by 'n ander depot, syspoor of
verwerkingsgebied (nie die finale bestemming nie). Aangesien die toestand van
bospaaie toenemend verswak en omdat swaarpadvervoer nie langer vakke kan bereik
nie, word vervoerkontrakteurs al hoe meer gedwing om van depots gebruik te maak
waarheen hout deur middel van SIV vervoer moet word. Die hout word dan weer daar
gelaai en na 'n verwerkingsfabriek vervoer deur middel van swaarpadvervoer.
'n Landwye opname het getoon dat die swak toestand van bospaaie toegeskryf kan
word aan oormatige paddigthede, onvoldoende befondsing vir die instandhouding/
opgradering van paaie en 'n gebrek aan begrip vir die belangrikheid van die onderhoud
van pad infrastruktuu r. Die totale kostes aan padverbeterings en opgraderings in die
pulphout bedryf, het van 1997 tot 2000 met R18.55 miljoen toegeneem. Verdere
opnames toon egter dat ten spyte van hierdie verhoging in befondsing, die toestand van
bospaaie steeds onbevredigend is.
Van die totale jaarlikse pulphout inname van 9.39 miljoen ton gedurende 1998, word
3.7 miljoen ton aan SIV blootgestel. Van die volume word 2.5 en 1.2 miljoen ton
onderskeidelik vanaf die stomp en pad na depots vervoer. Die opname het ook
landboutrekkers met leunwaens ge·identifiseer as die gewildste houtvervoer middel
tussen die stomp/pad en depots. Hande-arbeid en driewielbloklaaiers is op hulle beurt
verantwoordelik vir die laai van onderskeidelik 0.6 en 2.1 miljoen ton pulphout wat deur
middel van SIV vervoer word.
Inligting uit die opname ondersteun deur nuutgeskepte vakterminologie, is gebruik om
verskillende vervoersisteme vir die ekonomiese analise van totale koste van die
verskillende vervoerfases te bereken. 'n Netwerk analise model en pixel gebaseerde
GIS is in kombinasie gebruik om verskillende vervoer scenarios in drie areas in Kwa-Zulu Natal te ontleed, wat gebruik maak van SIV op swak bospaaie met hoenetwerkdigthede.
Die eenvoudige pixel-gebaseerde GIS het inligting weergegee oor
bospadnetwerke, oppervlakbedekking en hellings.
Die behoefte aan die vermindering van paddigtheid en die verbetering van bospaaie as
sulks, is deur die resultate van die ekonomiese ontleding na vore gebring. Dit sal die
behoefte vir uitgebreide primers vervoer uitskakel en die gebruik van tradisionele swaar
padvoertuie moontlik maak.
Die resultate van hierdie opname toon dat die bedryf addisioneel gemiddeld R43.25
miljoen/jaar of R8.24/m3 betaal vir die 3.7 miljoen ton wat onderhewig is aan SIV. Vir
die totale 9.4 miljoen m3 het SIV die maatskappye gedurende 1998 R4.60 meer gekos
vir elke m3 wat vervoer was.
Sleutelwoorde: Netwerkanalise. Houtvervoer. Sekondere vervoer. sekondere
intermediere verveer. Sekondere terminale vervoer. VerJengde prirnere vervoer.
Kortafstand vervoer. Pixel-gebaseerde GIS
Nota: In hierdie document word deurgans 'n punt (.) gebruik om desimale van
heelgetalle te skei.
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The effect of South African provincial road condition on the efficiency of forest product transportNicholls, Stephen John 03 1900 (has links)
Thesis (MScFor)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: The context of the study is concern over declining provincial road condition due to
insufficient government funding of road maintenance. These roads are by their
public nature used by a wide variety of commercial and private interests contributing
a variety of axle loads. There was no information available on the use of these roads
by forest companies and the road conditions. Consequently a survey was conducted
to determine condition and length of each segment of provincial road in use by
forestry companies and the volume of wood transported over them. In addition data
was gathered on other users and their contribution to the volume transported over
each section.
The questionnaire indicated that the provincial roads are in a poor state. The
literature review suggested a significant reduction in total cost of transport can be
achieved by maintaining or rebuilding these roads. South African forest companies
provide the majority of the heaviest axle loading to these roads and must theretore
take responsibility tor damage caused to them. Also a variety of forest companies
use the same roads and consequently collaborative studies between companies are
needed.
A modified Dijkstra's algorithm was used to quantify the effect of the condition of
South African provincial roads on the efficiency of the transport ottorest products.
The model requires digitised raster road and forest map layers combined with
transport vehicle specification as input. The products of the model are optimum
routes from all source points to a single exit point or sink, the total volume
transported across all road nodes and the total cost to extract all wood from a map
section. This output allows managers to identify critical roads tor management
attention and make tentative estimates of possible reductions to total cost by altering
the road condition. The manager is able to test the sensitivity of the solution to
changes in variables and gain a better overall picture of the interactions within the
system. The model results, and improved understanding, will provide input to more
specific and collaborative studies.
South African forest managers can respond to the poor provincial road network by
conducting ad hue maintenance to these roads to prevent them becoming completely
impassable or to rebuild them to their design state and maintain them at that state.
The cost of taking no actions is that these roads would eventually become
impassable. The road network model determined that, for the study area, a unilateral
decision to rebuild and maintain all roads would result in a net increase in transport
costs ofR 2 million/year. When compared to the cost of ad hue road improvements
for the same area of R 8 million it is obvious that proper road management is a better
option.
It was shown that 75% of the reduction in total cost is generated by improving only
31 % of the provincial road surface. Consequently, by improving selected roads
(20% of the total provincial road network for the area) it was possible to generate a
net cost R 2.9 million lower than if the roads were left as they are.
If reductions in operating costs are included the net cost to the forest industry is R 3.1
million/year lower than leaving the roads as they are. In addition to the cost being
lower, an improved road network would be in place and the current ad hue spending
would be unnecessary.
On a larger scale it was estimated that poor provincial road management costs the
industry as a whole R 26 million or R 1.52/m3/year. This money can be used to
offset the costs of maintaining and upgrading roads. It is therefore concluded that the
South African forest industry needs to assess its policy on provincial road
management and become more active in the managing of these roads. The tool
developed and presented is intended as a prototype decision support tool in
developing future policies. / AFRIKAANSE OPSOMMING: Die inhoud van hierdie studie handelaar die verval van provinsiale paaie as gevolg
van die regering se onvoldoende fondse vir die instandhouding van die paaie.
Hierdie paaie word as gevolg van hulle publieke aard deur 'n wye verskeidenheid
kommersiële en private belange gebruik, wat bydra tot 'n verskeidenheid van
asladings. Daar was geen inligting oor die bosbou maatskappye se gebruik van paaie
of die toestand van die paaie beskikbaar nie. Gevolglik is 'n opname gemaak 0111 die
kondisie en lengte van elke segment van die paaie wat deur die bosbou maatskappye
gebruik word, vas te stel, asook die volume hout wat oor die paaie vervoer word.
Data oor ander verbruikers van die paaie is verder ingesamel, asook hul bydrae tot
die volume wat oor die paaie vervoer word.
Die vraelys het aangedui dat die provinsiale paaie in 'n baie swak toestand is. 'n
Literatuurstudie het getoon dat 'n beduidende daling in die totale vervoerkoste
moontlik is deur hierdie paaie te onderhou afoor te bou. Die Suid-Afrikaanse
bosbou maatskappye voorsien die meerderheid van die swaarste asladings op hierdie
paaie en moet dus verantwoordelikheid neem vir beskadigde paaie, 'n
Verskeidenheid bosbou maatskappye gebruik die paaie; gevolglik is gesamentlike
studies tussen die maatskappye ook nodig.
'n Aangepaste Dijkstra algoritme is gebruik om die effek van die toestand van Suid-
Afrikaanse provinsiale paaie op die effektiwiteit van die vervoer van bosbou
produkte, vas te stel. Hierdie model benodig digitale inligting oor die hoofen
bosbou paaie, asook die spesifikasies van die voertuie wat gebruik word. Die
resultaat van die model is die optimale roetes vanaf alle bronpunt oorspronge tot by
'n enkele bestemming, die totale volume vervoer oor al die padnodusse en die totale koste verbonde aan die verwydering van alle hout uit 'n afgemerkte seksie op die
kaart. Hierdie produk of result ate stel bestuurders in staat 0111 kritieke paaie vir
aandag te identitiseer en om tentatiewe voorspellings van moontlike afname in die
totale kostes te maak indien die toestande van paaie verbeter sou word.
Die bestuurder kan die sensitiwiteit van die oplossing vir variasie in die
veranderlikes toets en sodoende 'n beter geheelbeeld kry van die interaksie binne die
sisteem. Die resultate van die model en n beter begrip daarvan, kan insterte lewer in
meer spesitieke studies en gesamentlike studies tussen maatskappye.
Suid Afrikaanse bosbou bestuurders kan teen die swak provinsiale padnetwerk
optree deur ad hoc instandhouding toe te pas op hierdie paaie om te voorkom dat
hulle totaal en alonbegaanbaar word. Ofhulle kan die paaie restoureer tot hul
oorspronklike toestand en hulle dan in stand hou. Die kostes daaraan verbonde om
nie op te tree nie, is dat hierdie paaie uiteindelik on-gaanbaar sal word. Die
padnetwerkmodel het gewys dat vir die spesitieke studie area, 'n eenparige besluit
0111 alle paaie te herbou en onderhou, 'n algehele toename in vervoerkostes van R2
miljoen/jaar tot gevolg sal hê. Wanneer dit vergelyk word met die R8 miljoen wat
die ad hoc padverbeterings kos, is dit duidelik dat geskikte padbestuur 'n beter opsie
is.
Daar is bewys dat 75% van die daling in totale kostes genereer kan word deur
verbeteringe aan die oppervlaktes van slegs 31% van die provinsiale paaie te maak.
Gevolglik was dit moontlik om netto kostes van R2,9 miljoen ruinder te genereer as
vanneer geen instandhouding gedoen is nie. Dit is bewerkstellig deur verbeteringe
aan geselekteerde paaie aante bring (20% van die totale provinsiale padnetwerk vir
die area.)
As die daling in bedryfskoste ingesluit is, sal die netto koste vir die bedryf R3.1
millioen/jaar ruinder wees as om die paaie so te los sonder enige aandag. Verder, tot
laer koste sal daar 'n verbeterde pad netwerk in plek wees en die huidige ad hoc
spandeering aan die paaie nie meer nodig wees nie. Op groot skaal, is die benaderd voorspelling dat 'n swak provinsialepadbestuurstelsel
die bosbou bedryf R26 millioen of R 1.52/m3 uit die sakjaag. Hiedie misbruikde
geld kan eerder teruggeploeg word in pad onderhoud en opgradeerings
werksaamhede. Dit is dus nodig dat die bosbou bedryf sy beleid weer in oonskou
moet neem in verband met die bestuur van provinsiale paaie en ook meer aktief die
voortou sal moet neem in die instandhoudind van provinsiale paaie. Die metodiek
hier ontwikkel kan 'n inleidende doel dien in die ontwikkeling van toekoemstige
besluit neeming rakend die bestuur van provinsiale paaie.
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