Better access by vehicle for locals and visitors.
Preserve this World Heritage site.
Works prevent major flooding damage. New paths created.
Stabilise land and improve transport links at World Heritage site
Jackfield is located 1km downstream of Ironbridge on the south side of the River Severn in the Ironbridge Gorge, Shropshire and is part of a UNESCO designated World Heritage site. It is also the site of an historic landslip which has seriously affected residents, industry, rail and road transport since the early 1700s. There is only one road across the slip.
Back in 1952 a landslip moved approximately 17m into the river causing a partial blockage and major structural damage to houses and roads. In 1982 a further smaller landslip cut off the only through road with a permanent diversion of vehicles along the higher abandoned railway track bed, itself on the move and laid over with timber boards for easier maintenance.
The primary objective of this technically demanding and complex project was to stabilise a 350m length of moving hillside which could cause a landslip into the river causing a blockage and upstream flooding.
This has now been eliminated and the stabilisation has also allowed for improvement of transport links back into the area with a new road.
The main works involved the installation of around 2,100 10m piles in 9 rows across the hillside. These were designed to penetrate just past the slip plane which exists about 7m underground and to resist against further movement.
Councillor Richard Overton gives a drop-in session on the Jackfield Stabilisation Project
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2,100 piles were installed using approximately 21km of steel tube, enough to stretch from Ironbridge to Shrewsbury. 6000m3 of wet concrete was poured into the ground to make the piles.
Temporary piling platforms had to support a 100 tonne piling rig and 60 tonne service crane. There was a real risk that bigger slippages could be triggered.
After the 1952 major slip academic studies were produced which the geotechnical world still regards as the classical treatise for clay slopes.
Project achievements and benefits
The geotechnical solution adopted by Jacobs as the principal designer uses piles installed to below the slip plane. Nine rows of closely spaced 600mm diameter piles were needed approximately 25m apart up the hillside.
The piles were constructed by a piling rig drilling a vertical circular hole and then pumped full of wet concrete. Steel tube reinforcement was then plunged into the hole. Advance grouting works were carried out to infill any shallow mine workings that might be present.
To eliminate further toe erosion at the river, the bank was excavated and revetted with large stones and a row of smaller 250mm diameter piles installed along the crest to further stabilise against local slippage.
The scheme fulfils the council’s and UNESCO sustainability obligations to safeguard the fabric of the World Heritage site and mitigates against an estimated minimum £200m community flooding cost.
Environmental value was achieved through geotechnical excellence both in design and construction as well as providing above ground benefits to the local community.
The added value is a new stable road serving the Jackfield community, delivering easier access to homes and greater visitor attraction to the local businesses, museums and new public open spaces. Emergency vehicles such as fire engines and ambulances can now access the furthest dwellings.
Additionally areas of mining spoil and clays which could have polluted the river have been successfully stabilised behind the piles.
New footpaths and riverside walks were created across the newly landscaped slip area. A scenic picnic area was constructed with a colourful tiled retaining wall depicting local children’s view of the works along with an artist’s interpretation of the landslip and underlying geology.
Upatikanaji bora kwa gari kwa wenyeji na wageni. Kuhifadhi eneo hili la Urithi wa Ulimwengu. Kazi kuzuia uharibifu mkubwa wa mafuriko. Njia mpya ziliundwa. Jackfield ni mji wa Uingereza uliojengwa katika eneo la Ironbridge, karibu na mto Severn, katika eneo la Ironbridge Gorge, Shropshire, na ni sehemu ya UNESCO World Heritage Site. Pia ni eneo la ardhi ya kihistoria ambayo imeathiri sana wakazi, viwanda, reli na usafiri wa barabara tangu mapema miaka ya 1700. Kuna barabara moja tu inayovuka mteremko huo. Mwaka 1952 mvua ya ardhi ilivuka na kuingia ndani ya mto huo kwa urefu wa mita 17 na kusababisha kuingiliwa kwa sehemu ya mto huo na uharibifu mkubwa wa majengo na barabara. Mnamo mwaka wa 1982, maporomoko mengine madogo yalikatiza barabara pekee ya kupitia na kugeuza mara kwa mara magari kando ya sakafu ya reli ya juu iliyokuwa imeachwa, yenyewe ikisafiri na kuweka bodi za mbao kwa ajili ya matengenezo rahisi. Lengo kuu la mradi huu wa kiufundi na wa kiufundi lilikuwa kuimarisha mwinuko wa mita 350 ambao unaweza kusababisha kuanguka kwa ardhi ndani ya mto na kusababisha kufungwa na mafuriko ya mto. Hii sasa imeondolewa na utulivu pia imeruhusu kuboresha viungo vya usafiri kurudi katika eneo hilo na barabara mpya. Kazi kuu ilihusisha kuanzisha karibu 2,100 10m piles katika safu tisa katika mteremko. Hizi zilitengenezwa kupenya tu nyuma ya ndege ya kuteleza ambayo ipo karibu mita 7 chini ya ardhi na kupinga harakati zaidi. Mjumbe wa Halmashauri ya London Richard Overton ametoa hotuba ya kuelezea kuhusu mradi wa Jackfield Stabilisation Project, ambapo vipande vya chuma vilivyofikia kilomita 21 vimejengwa, vikiwa na urefu wa kilomita 21 kutoka Ironbridge hadi Shrewsbury. Kwa mfano, kwa mfano, kwa mfano, kwa mfano, kwa mfano, kwa mfano, kwa mfano, kwa mfano, kwa mfano, kwa mfano, kwa mfano, kwa mfano, kwa mfano, kwa mfano, kwa mfano, kwa mfano, kwa mfano, kwa mfano. Vituo vya muda vya kuunganisha vililazimika kuunga mkono rig ya kuunganisha ya tani 100 na crane ya huduma ya tani 60. Kulikuwa na hatari halisi kwamba maporomoko makubwa zaidi yangeweza kusababishwa. Baada ya 1952 utafiti mkubwa wa kitaaluma ulifanywa ambayo ulimwengu wa geotechnical bado unaona kama insha ya kawaida kwa mteremko wa udongo. Mafanikio ya mradi na faida suluhisho geotechnical iliyopitishwa na Jacobs kama mbuni mkuu hutumia piles imewekwa chini ya ndege ya kuteleza. Mstari wa tisa wa mihimili yenye kipenyo cha 600mm ilihitajika karibu na mita 25 mbali na mteremko wa mlima. Vituo hivyo vilijengwa kwa kutumia mashine ya kuchimba vilele ambayo ilichimba shimo la mviringo na kisha kuijaza kwa saruji iliyokuwa imevunjika. Kisha, mabomba ya chuma yaliingizwa ndani ya shimo hilo. Kazi za kusukuma mapema zilifanywa ili kujaza kazi zozote za chini za mgodi ambazo zingeweza kuwapo. Ili kuondoa zaidi erosion toe katika mto, benki ilikuwa kuchimbwa na revetted na mawe makubwa na safu ya ndogo 250mm kipenyo piles imewekwa kando ya kilele ili zaidi kuimarisha dhidi ya slippage ya ndani. Mpango huo unakidhi majukumu ya baraza na UNESCO ya uendelevu ili kulinda muundo wa tovuti ya Urithi wa Ulimwengu na kupunguza gharama ya chini ya £ 200m ya mafuriko ya jamii. Thamani ya mazingira ilifikiwa kupitia ubora wa geotechnical wote katika kubuni na ujenzi pamoja na kutoa faida juu ya ardhi kwa jamii ya ndani. "Hii ni pamoja na barabara mpya ya kudumu inayohudumia jamii ya Jackfield, kutoa ufikiaji rahisi kwa nyumba na kuvutia zaidi wageni kwa biashara za mitaa, makumbusho na nafasi mpya za umma. """ Magari ya dharura kama vile magari ya kuzima moto na magari ya wagonjwa wa haraka sasa yanaweza kufika kwenye nyumba zilizo mbali zaidi. Kwa kuongezea maeneo ya uharibifu wa madini na udongo ambao ungeweza kuchafua mto yamefanikiwa kudumishwa nyuma ya vilele. Njia mpya za kutembea na kutembea kando ya mto ziliundwa katika eneo jipya la kuteleza. Eneo la picnic lilijengwa na ukuta wa kuhifadhi wa rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi ya rangi.