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ABSTRACT Our team has been commissioned to carry out a feasibility study of Whitby outer harbour area in order to produce an outline solution for the partnership of the Whitby Redevelopment Corporation (WRC). The design solution proposed by the team should be consisted of three elements of study: 1. Site investigation 2. Feasibility study 3. Detailed design The fishing and bulk cargo handling are in decline, which as a result increases unemployment in the area. The tourist and leisure industry are experiencing steady growth. However, those two upcoming industries have limited season (Starting around Easter to end of September). There is a possibility to expand on the tourist and leisure facilities in Whitby. The facts above indicate that more people will be attracted in the town; hence more traffic (pedestrian, vehicle and vessel) is likely to be generated in the area. Park and ride facilities will be built next to A171, on the west side of the Caedmon school, in order to avoid parking congestion in the town centre. The existing rail station/rail track will be used as a mean of transporting people to the city, as well as small ships and buses that would transfer the people in our site. In addition to all the above, a new road will be constructed, in order to give access to our site for the disabled people, and in case of an emergency. The final solution proposed is to build, in the area that we have been provided with, a yacht club, a restaurant and a number of shops that will attract the locals and the tourists that want to do their shopping. Furthermore, the viable solution will contain a marina, where the members of the yacht club will be able to leave their boats. CONTENTS 1. INTRODUCTION 2. SITE INVESTIGATION 2.1) Geographical position of Whitby 2.2) Political and social factors affecting Whitby 2.2.1) Fishing 2.2.2) Lack of job vacancies 2.2.3) Tourism 2.2.4) Port 2.3) Traffic infrastructure in Whitby 2.3.1) Vehicle traffic 2.3.2) Pedestrian traffic 2.3.3) Road safety 2.4) Climate 2.4.1) Weather conditions 2.4.2) Chloride attack 2.4.3) Sulphate attack 2.4.4) Sea scour 2.4.5) Driving wind & rain 2.5) Geology 2.5.1) Cliff instability 2.5.2) Site reconnaissance 2.6) piers 2.7) Public opinion 3. INITIAL CONSIDERATIONS 3.1) Yacht club 3.2) Cargo warehouse 3.3) Shopping centre 3.4) Cinema – room for social events 3.5) Cafe – bar – restaurant 3.6) Casino 3.7) Low cost houses 3.8) Hotel 3.9) Museum 3.10) Transportation solution 4. SINGLE VIABLE SOLUTION 4.1) Introduction 4.2) Building specification 4.2.1) Yacht-club 4.2.2) Restaurant 4.2.3) Shops 4.3) Expansion of the reclaimed land 4.3.1) Method of construction 4.4) Temporary work 4.5) Excavation 4.6) Dewatering of ground 4.7) Support for excavation 4.8) Piles 4.9) Piling methods and pile-driving equipment 4.10) Foundation construction 4.11) Construction methods 4.11.1) Construction of the ground floor 4.11.2) Construction of the upper floor 4.11.3) Design and construction of the roofs 4.11.4) Walls and partitions 4.12) Material considered 4.13) Marina 4.13.1) Under-water excavation 4.13.2) Construction method of external wall 5. PROPOSALS OF THE EAST AND WEST PIERS 5.1) Preparation before construction 5.2) Under-water excavation 5.3) Construction of the seawall 5.4) Reconstruction of the two piers extensions and maintenance of the piers 6. SOLUTION TO THE TRANSPORTATION INFRASTRUCTURE PROBLEM 6.1) Transportation to and from the site, by boat 6.2) Park and ride 6.3) Extension of the Henrietta street 7. RECOMMENDATION TO THE CLIENT 1. INTRODUCTION During the site investigation that took place at the Whitby area, several amounts of information were collected, especially for the outer-harbour area. At the first-stage, general information was gathered from the following sources: From meeting with North Area Engineer Mr John Woodhead From several books, maps, newspapers and articles from the library of Whitby Dr. Jess Boot, Professor Steve Garrity, Professor Ashley Tourist office Harbour office Captain cook museum, Whitby museum, lifeboat museum Whitby gazette Abbey museum At the second-stage additional information, for the geology of the Whitby area was gathered, during the surveys and inspections that were organised by Dr Chapman. During the last-stage of the site investigation, public surveys were carried out in order to consider the opinion of the local people, about the local problems and the solutions that they purpose. Moreover, considering the site investigation and the information we gathered, proposals for the Outer Harbour Area and the East &West piers will be appraised, as well as solutions to the transportation infrastructure problem. 2. SITE INVESTIGATION 2.1) Geographical position of Whitby Whitby is a town which lies on the North Yorkshire. It is 20 miles far away from Scarborough and Middlesbrough. The town of Whitby has an excellent archaeological and pre-historical character. During the summer season it is a nice place for holidays, and many tourists visit the town. There are three road links to the town: The A171, a coastal road to Scarborough, to the south-east, which also continues through Whitby to Teesside, to the north-west The A174 , a coastal road to Redcar in the west-north-west The A169, which traverses the north Yorkshire, moors to Pickering. There is and one rail link to Whitby from Teesside area. Also Whitby is a major shopping town for the north Yorkshire and many industries are grown or declined to this area. 2.2) Political and social factors affecting Whitby 3.2.1) Fishing The fleet of fishing-boats consists of 25 keel boats, 40 motor cobles and about 5 salmon cobles. Several types of fishing is used from keel boats: trawl, seine, drift, line. The large boats go out for more than two days, and the smaller go out early in the morning and return late in the afternoon. Their catches contain cod with a little haddock, plaice, whiting and skate. In the period of May until August there are salmons in the river, and many small open boats are licensed to net these off the harbour entrance. From 1958 until 1970 there was herring fishing at Whitby, but it has disappeared totally. 2.2.2) Lack of job vacancies One major problem at Whitby, is that there are few job opportunities for young people. At an early age, they move away to other town and cities. On the other hand, tourism provides some work, and this will be an expansion in this field. Another problem which is created from this situation, is that there is a great age difference between the people who live at Whitby. 2.2.3) Tourism Whitby is a popular place for holidays. According to the Scarborough borough council, there are 3610 bed spaces (according the statement 1999), and most of them are serviced. During the summer season more then 500,000 tourists visit Whitby. Many tourists’ facilities exist at Whitby. Daily cruises with boat, which tours the visitors to the coast. There are many museums, as the Captain Cook museum, the Dracula museum, and the Whitby museum, which contain much information’s for the culture and the history of the Whitby. In the museums, someone could find ships and men from Whitby, who had been travelling the globe, fishing for whales in the arctic, fighting the African slave trade and exploring the South Seas. There is also one library, which has many books and articles with the history of Whitby. Many visitors visit the 11th century Abbey on the east cliff, and the old town on Church Street. General, tourism is an increasing industry in the area, and its revenue for the Whitby is close to £34 million per year. Also tourism increases the employment vacancies at Whitby, and more than two thousand people work for this industry. 2.2.4) Port The port of Whitby lies 264 miles from Rotterdam and 415 miles from Bergen. It is owned by Scarborough council, which employs 18 staff to maintain and operate the port. The facilities which the port offers, are available at the Endeavour and Timber Wharves. From 1958 until 1999, the port had an interesting activity, and especial at 1980’s, more than 60 cargoes passed the port and more than 30,000 tonnes were transferred annually. The cost of ship access is low, compared with other ports. The major problem of the port, is that there are not enough storage places. This is the major reason which stops/decreases the transportation at the port. 2.3) Traffic infrastructure in Whitby 2.3.1) Vehicle traffic First of all, it has to be mentioned, that during our visit at Whitby, we all realized that it is a very congested place. Although it was the end of the holiday season, the traffic problem was still very easy to be noticed. Most of the streets, and especially the ones at the town center, are very narrow, and as a result, they have to be one-way. There are too few parking spaces available for residents in some areas, and this is not improved by visitor parking in residential streets. The parking spaces are being lost, due to the existence of buildings on the existing car parks, and they are too few available for visitors, particularly at peak times. But, it must be mentioned, that even if there were some more available parking places, the problem would still exist, due to the poor advanced information for drivers, concerning the parking spaces available. During our visit at Whitby, we also realized that the routes to the main car parks via junctions, cannot handle the large volumes of traffic passing through, resulting in long traffic queues. Too many visitors drive to the Marina and Church Street car parks, in order to search for parking spaces, which, of course, are often not available – this causes congestion! Finally, it must be emphasized, that the overflow parking arrangements are poorly designed, with grass surface not suitable in bad weather. Available parking at Whitby Short Stay (Max Stay 3 Hours) Map Key Spaces Cliff Street CS 37 Marina Front MF 96 St Hilda’s Terrace (open to the public on weekends and Bank Holidays only) SHT 20 Medium - Long Stay West Cliff Map Key Spaces Spa Drive SD 68 Spa Top ST 63 West Cliff WST 674 Medium – Long Stay Abbey Car Parks Map Key Spaces Abbey Plain AP 29 Abbey Headland AH 415 Multi – Long Stay Harbour Car Parks Map Key Spaces Church Street CST 92 Marina Back MB 320 2.3.2) Pedestrian traffic At this point it must be emphasized, that there are only two options, in order to get across the river: either across the Swing Bridge situated in the town center, or by the main road over the high-rise bridge on the edge of town. The second option is fine enough for the cars, but the first one is not that good for the pedestrians, and as a result, pedestrian congestion is caused, especially during high season, where thousands of tourists visit the town of Whitby. It was also noticed, that the disabled and wheelchair access is very inadequate, and the pedestrian routes are poor in places. The bus stops have lack of facilities, such as: shelter, bus information, seating, room for queuing, and good access on and off the bus. Also, the coach drop-off/pick-up and parking is inadequate, and causes problems to the pedestrians. 2.3.3) Road safety Due to the big traffic problem, which exists at the Whitby area, there are too many traffic accidents which cause injury to pedestrians and other road users. One thing that really got our attention and concern was the fact that the vehicles were entering the pedestrian roads during ‘pedestrian’ hours, and as a result, many dangers were emerging from that fact. We also noticed prohibited vehicles using ‘access only’ roads, as also many conflicts between pedestrians and vehicles on Swing Bridge, Pier Road and the lower part of Church Street. There were also speeding problems on most of the routes, something that also could cause possible accidents. Finally, there are another 2 very important problems that have to be solved as soon as possible. First of all, there is a great need for safer walking routes to the schools of Whitby, in order to protect the children from the heavy traffic. Also, due to the congestion, the cycling is thought to be rather dangerous, and of course, there is a need to improve routes and make it safer. 2.4) Climate 2.4.1) Weather conditions The general kind of weather conditions at Whitby can be observed by taking a walk around the town. Many signs of very severe weather conditions can be expected, especially with respect to the structures. Saline conditions, chloride attack, sulphate attack and sea scour are some of the signs that can be pointed out, if we take a close look at the structures. 2.4.2) Chloride attack As mentioned before, there are very severe weather conditions on the East Coast of Britain, although some of them are more obvious than others. Chlorides are present in seawater and de-icing salt, which turns it to a very particular problem when dealing with some specific kinds of structures in coastal environments. Usually, chlorides attack the steel in the reinforced concrete, which depends on oxygen and levels of moisture. The level of chloride attack depends on the climate of the area that is being investigated. When an area is occasionally dry or occasionally wet, the problem is most prominent. In this case, the steel can be subjected to oxygen and moisture, and as a result, corrosion takes place. In order for the corrosion to take place, the chlorides have to penetrate through the steel in large quantities. Therefore, in order to prevent chloride attack, we have to provide enough cover to the reinforcement, compact the concrete well and apply a protective coating to the concrete. Moreover, the addition of pulverized fuel ash can help to protect the reinforced concrete against chloride attack. There was much evidence of chloride attack, the first of which was seen on a concrete bus stop post. Some parts of the concrete had cracked and fallen off, as a result of leaving some of the steel reinforcement bar exposed to the weather, which had rusted, and therefore, weakened the post. Some of the reasons for this situation are: not enough cover to the reinforcement, and poor compaction of the concrete. 2.4.3) Sulphate attack Seawater contains sulphates, which attack the concrete by permeability, diffusion, or absorption. Same as the chloride attack, submerged concrete is less prone to sulphate attack, because a protective layer can be built up, making the outer part of the concrete less permeable. On the other hand, in drying and wetting areas, as the water evaporates, salt can crystallize onto the surface of the structure, making it more prone to these kinds of attack. Moreover, these areas can also suffer from freeze/thaw attack, which in this case the water freezes in the pores and as a result, voids in the concrete expand and cause parts to crack and spall off. Therefore, in order to prevent these kinds of attack, low permeability concrete should be used, or cement replacement materials, such as pulverized fuel ash. 2.4.4) Sea scour Sea scour can be observed at the concrete steps, which give access down to the sea and onto the beach. It is more obvious at the lower steps. This is due to the abrasive action; the waves have upon the concrete, making the edges of the steps rounded. 2.4.5) Driving wind & rain Driving wind and rain and some other very severe weather conditions, which were mentioned before, such as sand particles, are present in the wind and consist to the abrasiveness of the whole weather system. In many parts of the town there are brick walls, which due to their age and the wind, have whole bricks grinded away. 2.5) Geology The geological character of the town of Whitby is an important issue, in order to assess the development of the area. The geology of the coastal and harbour area, consists mostly of sandstone and shaly deposits, dating back from the later Jurassic period. An important issue that must be taken into account, is the weathering process occurring and its influence on the coast. Therefore, any structure proposed at the Whitby cliffs must have protection, if durability is to be achieved. The cliffs already have some kind of protection. Considering any proposal for a coastal structure, we must also think about further protection of the cliffs, as well as for the structure itself. At the mouth of the harbour, clear evidence of salty deposits can be observed, with a very distinctive discontinuity. These deposits are the result of the settling silts from the River Esk, as it enters the sea. On the East side of the harbour, evidence of alum shale is present. There are also signs of well-defined sandstones and mudstones. Receding process is taking place within the cliff, as well as on the west side. The latter shows traces of anaerobic decaying, and deposition of living orgasms having taken place. The outcrop shows presence of alum shale and bituminous shale. This evidence can also be confirmed by the high presence of fossils within the alum shale, and at the foot of the cliff. On the West side of the harbour, it can be observed that the cliffs have the same level, with lands of grass on top. There is evidence of circular slips, which have probably occurred due to glacial action during the late Pleistocene epoch. Moreover, signs of glacial tills can be observed at the foot of the cliff. The first outcrop of the rock consists of a yellowish-brown coloured formation of sandstone. The colour marks show the presence of iron oxides (FeO). The western cliff shows layers of shale material and mudstones. As well as at the east cliff, some parts of the west cliff have undergone some protection works, consisting of brickwork and timberwork. 2.5.1) Cliff instability There should be some work done, in order to repair the storm-damaged cliffs. The cliffs of Tate Hill have to be repaired, after suffering land movement, following torrential rain. This plan should start by stabilizing work beneath the Tate Hill. It should also involve the construction of concrete shear hays (buried concrete buttresses) to support the cliff, a new wall, and drainage work, in order to stabilize the area of land which had been slumped, following the down poor. The second part of this scheme includes the work required to remove the area of slumped land, and pin in a soil stabilizing mesh to strengthen the cliff. The mesh will be buried from view, once the land has been re-seeded. So, this whole work tackles another area that has suffered movement, following heavy rains and storms. It will stabilize the areas of land involved, and hopefully protect them against further movement in the future, by strengthening the cliffs and improving drainage. 2.5.2) Site reconnaissance The information (provided by the Scarborough Borough Council as well as gathered by the group so far) indicates that the soil condition of the site that we want to develop makes the construction of the foundations more complex and more expensive. The type of soil on which the proposed foundations will be built, is silt with almost non-shear resistance. Therefore, pile foundation must be used. Due to the fact that the soil has small shear resistance, it is not necessarily a bad thing for construction of the foundations. This could make the installation of piles much easier, than in the case of existence of different soil conditions. The work required for the deep excavation during the high season, could pose a potential hazard for both the pedestrians and traffic. Therefore, it is strongly recommended that all excavations should be completely barricaded and clearly visible, during the day as also the night. According to the available information, the first stratum (mudstone/sandstone) is around 14m below the riverbed level. This means that the piles should have to be driven around this depth, in order to get solid support on strata. Therefore, piles will be needed at the reclaimed land, due to the existing ground conditions. Piles can support the load of the structure in two ways. One is through friction from the soil against the side of the pile, and the other is where the pile is supported by hard ground at the end or bottom. End-bearing piles must be used, based on the assumption that the over lying soil has a low friction value. We should be using pre-cast piles than in-situ piles. The main reason for this, is to reduce noise levels for residents and tourists, as well as to save time during the period of the construction. The pre-cast piles can be made from either concrete or steel. Concrete piles should be used, since it’s safer, due to the danger of corrosion when using steel piles. According to the boreholes’ data, the soil strata is soft, and as a result, the driving of concrete won’t be difficult and will require the use of less hammer head force (less noise). Due to the weaker material that exists at the sides of the excavation, a retaining wall will have to be built. In order to prevent lateral bending, we can put reinforced steel into the piles, and hence, provide extra reinforcing, in order to resist stresses during handling. Protection from corrosion of the steel due to the existence of groundwater should be adequately provided, through the use of high-quality concrete, from which the piles will be constructed. Moreover, due to the presence of groundwater in the excavation, greater lateral pressures will be imposed on temporary or permanent works, and may require the use of pumps or well pointing during the construction. 2.6) Piers First of all, it has to be emphasized, that the exact day of the initial construction of the piers, is still not 100% known. The only thing known, is that in 1307, King Edward-I brought to light a customs grant to the Abbot of Whitby, ‘for a quay…newly to be constructed’. In 1539 the piers were already there, rebuilt with fallen stone from cliff and timber. About 1 century later, in 1632, the west pier was built or rebuilt in stone, by command of Hugh Chomley. One point that has to be emphasized is that in 1702, an act of parliament passed giving funds. The east pier was wholly built, the west pier was repeatedly enlarged and repaired, smaller piers inside were built to break the face of waves, and also, rock and several immense beds of sand were removed. A few years later, in 1734, the west-pier was lengthened 100 yards, that sandbanks accumulating might have washed away. Some years later, another 230 yards of old west pier were rebuilt, and later, still the whole pier faced with dressed stones, and east pier was dressed some time after. In 1814, the west pier was lengthened, and finished off with a circular end constructed as a battery with emplacements for 6 guns. It was faced with dressed stone of immense size, some single stones weighing 6 tonnes, and stones riveted together, and many mortised into each other. The east pier was dressed to make stronger, but was shorter than now (to the knuckle). In 1816, it was proposed to extend. 30 years later, it was extended by 325 ft. The fish pier was the last to be built. It must also be mentioned, that until October 1831, the harbour light at the end of the west pier, was a large copper lantern. At that year, the foundations for the new lighthouse were placed, and were finished 11 weeks later. First used on 5th October 1831. East pier lighthouse was built in 1854, about 11 years after the extension. It must be said, that the present extensions to the piers, were not completed until 1914. Another important date of the history of the piers, was the April of 1959. At that time, the west pier and extension were closed, as also the east pier was to be closed within a month for repair. Large cavities had been gouged by successive storms in the foundations of the extensions. Steel piles were sank round the concrete piers, at a distance of 3 ft. Then the cavities and intervening gap between the piles were filled with concrete down to the shale bed under the sand, widening the base of the extension by 6 ft. All the materials and machinery for the east pier, had to be ferried across the harbour by boat, from the west pier, including a 21 tonne excavator, sand, gravel and cement. Divers were employed to clear the sand from the foundations down to the shale, and to scour out sand from the wall cavities. On October of 1977, the sea wall repairs take place at the Western end of Happy Valley. Heavy seas and cliff erosion below the bathing pool were the cause for the damage. Cavities were 6 ft deep. Ciabion baskets filled with stones were set on the rock, hard into the cliff to prevent even the heaviest seas and largest tides getting behind the walls and causing similar damage. This whole procedure took about 6 weeks. 11 years later, on April of 1988, 3 million pounds were spent for the stabilization of west cliff, hoped to finish by end of summer of 1989. The cliff was re-surveyed, and equipment was brought up. A broken section of the sea wall from White Point to happy Valley was repaired, and an extension was made to the existing wall. Sea defences, a rock armour wall arrived from Norway. Their size was carefully calculated to match the sea conditions, and to resist wave action. The first barge load arrived in June of 1988. The stabilization of the cliff involved regarding and new drainage put in, to prevent further slippage. 2 years ago, on July of 2000, another 1.3 million pounds were spent for the protection scheme to shore up the eroding east cliffs with thousands of tonnes of rock defences were on track. The rocks, 8 tonnes each, had already been shipped to Whitby and put into place. No hitches or hold ups and continuous delivery of rock. The void between the end of the east pier and Haggerlythe, was to be filled in with rock armour, so the ladder would disappear, and a causeway at the top would link the two. The spa ladder was replaced a number of times over the years, but the new causeway would do away with it. Finally, last year, on Feb 2001, fish quay got 90,000 pounds facelift, new buildings, walls, fencing, gates and automatic traffic barrier allowing fishing lorries access to fish quay, therefore taking them off the roadside (PESCA) to ease congestion. Finished in March of 2001. Of course, it is still possible to see joints and lewis-holes (used for lifting the blocks), on the east pier.
Approximate Word count = 17812
Approximate Pages = 71.2
(250 words per page double spaced)
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