Civil Engineering, Highway Construction - Research Paper Example

HIGHWAY CIVIL ENGINEERING Contents List of Tables 2 0 Introduction 3 2.0 Background 3 3.0 Rationale for Project 5 4.0 Aim and Objectives 5 5.0 Methodology 6 6.0 Route Alignment Selection Discussion 8 7.0 Description of the selected Route 13 7.1 Historical, Recreational and Cultural Significance 13 7.2 Geological, Geometrical alignment and Geotechnical Challenges 14 7.3 Local Sources of Materials that could be used in Construction 15 7.4 Cross Sections for a 2 lane Highway 15 8.0 Conclusions 17 References 19 List of Figures Figure 1: Coastal route along the west coast of Auckland linking the city with Hamilton 4 Figure 2: Muriwai Coastal Environment 9 Figure 3: Map of the Raglan Beach 10 Figure 4: Map of the Raglan with indication of Termination Point 12 Table 1: Sub Base Strength Requirements 16 1.0 Introduction Once road construction projects take place, they do so with the future generation in mind. This is because it is only through this that highways that are constructed today can last longer and be of relevance to unborn generations, serving their needs in transportation. However, no matter how careful estimation into future needs may be done, achieving accuracy is almost impossibility. This is because the dynamisms of human demographic changes are almost unpredictable (Power and Elliott, 2006). Currently, it can be said that such a situation has gripped the people living around Auckland and Hamilton, and who constantly have the need to travel from one of these points to the other. This even because even though there are very beautiful road works with the best of civil engineering finishes, these road works are hardly meeting the travelling needs of modern generation. Consequently, the need to have alternative routes that are free from some of the most common challenges faced today such as traffic congestion is very important. But whiles doing this, it is important to try even harder that the needs of future generations will be catered for in creating the alternative route. This is why a thorough feasibility study into the proposed site for construction is a necessity that must not be underestimated at all. 2.0 Background Already, there are routes from Auckland to Hamilton. Most of these routes date back to several years when the state of development and urbanisation in the areas within the two towns were not as brisk as they have been in the past decade. Consequently, a lot of changes have been experienced in terms of infrastructural development. The problem that exists however has to do with the convenience with which road users and other motorist get while using the existing routes. This is because most of the existing routes go through major town that come between the two cities, thereby leading to massive traffic congestion, emanating from active town activities engaged in by the people of the various. Through urbanisation, almost every other town and city that comes between Auckland and Hamilton, including Mangere, Papakura, Pukekohe, and Huntly have become extremely busy places. Because of this, the 125 kilometre road that was expected to be plied in less than an hour and a half can take a motorist over two hours getting through (Butchers, 2009). This inconvenient situation has led to a number of recommendations being made on the way forward to easing traffic and making motorist more comfortable in travelling from Auckland to Hamilton. The location map of the area has been affixed below. Figure 1: Coastal route along the west coast of Auckland linking the city with Hamilton Source: Wises (2014) 3.0 Rationale for Project The current project is being carried out because of the need to solve the road traffic congestion situation that motorist face, travelling from Auckland to Hamilton, using existing highways. From the map attached, it will be noted that the current route is a highway that is found at a clearly urbanised area with very few forest land. Meanwhile, there is the coastal side that has hardly being utilised in terms of road construction. Through the effect of globalisation and the easing of inter-country movement for the purposes of business, education and tourism, most cities of the world including Auckland and Hamilton are becoming busier and busier because they receive a lot of visitors by the day (Butchers, 2009). It is important that for whatever reason that a person may be having the need to travel from Auckland to Hamilton, there should be a means of getting through the journey as quickly as possible. In the present state however, the number of public facilities such as schools, hospitals, offices, restaurants and hotels that have sprang up on the main highway from Auckland to Hamilton makes this ambition difficult to achieve. It is for this reason that the project is being done to find a lasting solution to the traffic situation that prevails on the identified route. 4.0 Aim and Objectives Based on the background and rationale given, the main focus of the project is to create an alternative coastal route along the west coast of Auckland that will link that city with Hamilton. Even though on the surface this may seem a very prudent approach to addressing the traffic situation that have been lamented above, there are important civil engineering technicalities that need to be clarified in order to justify the feasibility and achievability of the project. With the aim to create an alternative coastal route given therefore, there are specific objectives that need to be achieved before the main aim can be realised. These specific objectives have been indicated as follows: 1. To identify and document places of historical, recreational and culture significance along the proposed route. 2. To identify and analyse possible geological, geometrical alignment and geotechnical challenges that may be encountered in the course of the earthwork. 3. To identify and comment on the availability of local sources of materials that could be used in making the highway construction easier. 4. To find the best cross sections for a 2 lane highway that can give room for allowances for an extra 2 lane for future expansion purposes. 5.0 Methodology The methodological approach taken in the prospecting of the new coastal highway project is a quantitative method that requires the use of numeric indexes and all forms of calculated and mathematical documentations. To effectively deliver this quantitative project, the use of fieldwork was employed as a form of data collection process. This means that the engineer visited the site where the project is expected to take place and collected primary data that were analysed for all necessary decisions to be taken. Quantitative fieldworks of this nature have been explained to be very important in civil engineering as it brings the engineer closer to the real situation on the ground (Given, 2008). Alternatively to the use of quantitative fieldwork, some engineers have used qualitative review, which requires them to review documents about the site where the project is to take place and made decisions based on what they review. This has however been criticised to have a lot of shortcomings, giving the premise that it denies the engineer the opportunity to have a firsthand experience of what really prevails on the ground (Given, 2008). With the selected methodology, this weakness was totally avoided. As it is said in ordinary parlance, seeing is believing, and so it was important for the engineer to be on the field to have primary experience with what is on the ground. The quantitative fieldwork was very systematic in nature. This means that the engineer had a very specific procedure and approach that was followed in the course of collecting data and evidence gathering as part of the prospecting of the proposed site. One of the core systematic procedures was to first gain a vivid understanding of the topology of the whole area. This was done by making use of existing maps that were collected from various academic and professional sources including online sources. After this, the engineer had a thematic work schedule, which was based on the specific objectives stated for the project above. This means that each of the specific objectives was reconstructed into a task that the engineer had to perform. Based on the task, the engineer visited the site to collect firsthand primary evidence on such things as the historical, recreational and culture significance along the proposed route. The possible geological, geometrical alignment and geotechnical challenges along the route were also investigated. In the subsequent sections of the report, the outcomes of the main tasks that were performed have been presented and elaborated for onward decision making. It is worth emphasising that the prospecting and idea of the whole project will be to cater for future growth in both Auckland and Hamilton that would assist in alleviating traffic congestion. 6.0 Route Alignment Selection Discussion The overall route under prospection is the coastal route along the west coast of Auckland linking the city with Hamilton. This has been clearly depicted in the map in figure 1. But together to get through with this target, there are other micro routes that need to be aligned together in completing the project. The first is the need to have a new coastal highway that connects Muriwai Beach to Raglan. Figure 2 depicts the entire Muriwai Coastal Environment. But to connect the Muriwai Beach to Raglan, the road would have to go through the Raglan Harbour, which is on the west coast of the North Island of New Zealand. The Topo map of the Raglan Beach is also given to better exemplify this aligning route. At the Muriwai Beach, the starting point of construction will be the Oaia Road. But to connection exactly to Raglan, the exact point of connection shall be the Edwin Mitchelson Track. The justification here is to avoid the existing busy activity that exists on the main Oaja Road. Located in the Muriwai Regional Park, the Edwin Mitchelson Track gives spectacular view through the north of Muriwai Beach and avoids the busyness of the Oaja Road. Figure 2: Muriwai Coastal Environment Source: ec-3geo (2014) Figure 3: Map of the Raglan Beach Source: Raglan Surfing School (2014) The advantage that the alignment connecting Muriwai Beach to Raglan via the Raglan Beach would bring is that the Tokatara Rocks that are located on the east coast will be avoided. This means that construction through hard rocks, which will demand extra labour and machinery work, will be avoided (Cardno, 2008). Another alignment will be to go through the Waitakere Ranges. This is located to the east of Muriwai and has been noted for its environmentally sensitive composite areas. The environmental sensitivity mainly has to do with the chain of hills located in this area. The chain of hills cover very wide area, taking up to 25 km of the existing land space when measured from both north to south and west to central Auckland (Pratt, 2013). What is more, there are cliffs that exceed 300 m at the western coastline and several beaches (Pratt, 2013). The alignment through this area will therefore need much geographic readings, mostly done in an aerial manner so as to identify the shortest existing routes and the most construction friendly zones. But overall, much of the highway will be developed through the Waitakere Ranges, given the fact that the place is reserved to human habitants, making it have a free range of movement, devoid of artificial traffic created by human activities. The highway route is also expected to go through Bethells Beach, as well as Piha Beach. These two areas have much in common when it comes to their geographic composition and human habitation characteristics. For example, the place is very rich in sand, most of which have been left over as a result of the activities of the lower Waitakere River valley (Koduah, 2009). In terms of distance, Bethells Beach is around 30 kilometres north-west of Auckland City, which is expected to serve as both departure and arrival point after the highway has been constructed. The justification for including this area is that it will serve contractors very long break from the sensitive environment of the Waitakere Range. However, there are important considerations that need to be made while linking the route through Bethells Beach and Piha Beach. This consideration has to do with consultations that need to be cleared with community leaders as the places are currently occupied an approved for human activities. Some of the commonest activities that go on at this place include surfing, fishing, bush walking, sunbathing, and skim boarding (Koduah, 2009). A lot of film shooting is also done at the place and thus the need for necessary permission to be sought. Once the route gets to the more shipping busy destinations of Manukau Harbour entrance and Port Waikato, engineering provisions in the form of two separate bridge structures will be provided at these two centres. In order to ensure that shipping passage will not be inhibited, the bridge structures will be raised such that shipping passage can take place underneath them. This way, the shipping activities taking place at the sites will in no way become a hindrance to the need to ensure smooth and free flow of traffic. The end point of the highway will be Raglan. But for the same reason of avoiding rush human activities, the end point will not be made to cross the entrance of Raglan Harbour. With this said the need to providing for future expansion that can come in the form of possible connection with the existing State Highway network will not be denied. As a result, the proximity from the end point to the entrance of the Raglan Harbour will be taken into consideration so that even though the end point will not be at the entrance, it will be at such a point that can easily be stressed to link up with State Highway network. Most ideally thereof, the termination point of the highway will be the Haroto Bay. The justification here is that this point offers closeness to the harbour, whiles avoiding the busyness of it. What is more, the Bay is an ideal stop point for visitors and residents to have tourism and accommodation needs met. Below is a map of Raglan, showing where the termination point will be. Figure 4: Map of the Raglan with indication of Termination Point Source: Raglan Surfing School (2014) 7.0 Description of the selected Route From the route alignment selection discussion, the route to be used can be given as follows: Muriwai, Oaia Road (Edwin Mitchelson Track) → Waitakere Ranges → Bethells Beach → Piha Beach Communities → Manukau [Bridge] → Port Waikato [Bridge] → Raglan Harbour (Haroto Bay) This section of the report therefore addresses the specific objectives in thematic topics by focusing on the main sections and spots involved on the route. These sections and spots are Muriwai, Waitakere Ranges, Bethells, Piha, Manukau, Port Waikato, and Raglan. These sections and spots shall however not be discussed independently but in order of how each of them is relevant to the theme being discussed. 7.1 Historical, Recreational and Cultural Significance Muriwai has very rich history when it comes to the importance of the place as a recreational centre where several social activities take place at the Muriwai Beach. The commonest of these activities are surfing, fishing, bush walking, and surf boarding (BirdLife International, 2012). Even though horse racing is common, not the same can be said for active driving because there is history to cars getting stranded at the place. As explained earlier, the Waitakere Ranges does not have a lot of human activities taking place there as the location is not much aligned with social activities very common among tourists and other local residents. With both Bethells and Piha however, the recreational activeness of the places are much similar to Muriwai. This is because of the presence of beach activities, which attract foreigners, as much as local people. At Piha, there are not many people, as current records show a population of 600 residents (Ewen, Bruce and Graeme, 2007). There is however a cultural significance of the place, which is aligned to the way of life of the local people as being surf lifesavers (Ewen, Bruce and Graeme, 2007). It is for this reason that the Piha Beach was selected for the TV reality show, “Piha Rescue”, which is based on the theme of the cultural heritage of the local people. Manukau, Waikato and Raglan are however busier communities when compared to the previously discussed ones. This is mainly because of the commercialisation of port activities that take place there. 7.2 Geological, Geometrical alignment and Geotechnical Challenges Most of sections selected have very peculiar geologies that are of importance to the project to be embarked upon. For example, at Muriwai, there are known older volcanic materials and sedimentary rocks (BirdLife International, 2012). Even though the shore platform has been described as very solid and firmly jointed, the possible impact of the place as an old volcanic site is still being explored by geologists. This means that there is no perfect guarantee in terms of safety. The Waitakere Ranges is another area that calls for much attention when it comes to its geography. This is because there are very high hills at the place, some of which go as high up as 474 meters above sea level (Pratt, 2013). Whiles constructing, such features may pose major challenges and can increase the expected distance that must be covered in terms physical road length. This means that overspending is a possible problem that engineers may be confronted with if budgeting is not critically evaluated. There are also volcanic conglomerate and lave flows, even though no active volcano activity has been known to have taken place in 12-25 million years (Pratt, 2013). It can be emphasised that of the sections available, the section from Waitakere Ranges to Bethells Beach pose the most challenging geometrical alignment issue. Because of the hills that exist, the determination of curves for the designing of horizontal curves may be very challenging. The same applies to curve lengths and objects that may possibly obstruct viewing of drivers, given the hilly nature of the place. 7.3 Local Sources of Materials that could be used in Construction Areas within the route that promises to give some of the best local sources of materials for construction are Bethells Beach, Piha Beach and Waitakere. This is because of the nature of the soil in these areas. As for Waitakere, there would have to be the querying of stones to be used for construction. The two beaches have also been noted to have rich course sand that is ideal for filling to achieve levelling of construction areas. Stones and wood are other local materials that can be found in almost all the spots to be used as part of the route. Key among the areas to provide a lot of wood for various construction works are the places with rich forest lands such as Manukau, Waikato, and Raglan. This means that getting to the end point, there will be a lot of wood to be used. In terms of stones, Waitakere and Muriwai have the best promises due to the geography of those areas, which make them abound in so much rock. Last but not least, earth materials are expected to be present at almost all the points. Some of these earth materials are gravels, sand, soil, granular surfacing, and turf. The granular surfacing is however expected to be more in quantum at the beaches, where crushed shells are common. 7.4 Cross Sections for a 2 lane Highway Specific points on the route are expected to have typical cross sections created for a 2 lane highway, as well as allowance for an extra two lane expansion that will be used for future purposes. For example, right before the Manukau Harbour crossing, there will be 1 typical cross section that will be necessitated due to the busy nature of the harbour crossing with human activity. With the aim of the project in mind, another typical cross section will be provided between the Manukau Harbour crossing and the Port Waikato so as to avoid repeated events with human and vehicular traffic situations. What is more, right before Raglan where the highway is expected to close, there will be 1 typical cross section provided. Each of the bridges that will be elevated to allow for shipping passage will also have 1 typical cross section. To ensure durability and longevity, it will be ensured that the materials are clean and do not possess any organic matter that make decomposition possible (About Civil, 2014). These materials must also be roller friendly, such that they must easily be compacted by a roller. More specifically for the sub-base, there should be a coefficient (D60/D10) that is not less than 3 (About Civil, 2014). It is also expected that the fraction passing sieve #200 will not be beyond two thirds of fraction passing sieve #40 (About Civil, 2014). At the same time, the L.L should not be more than 25% and P.I not above 6 (About Civil, 2014). The table below summarises the sub-base strength requirements Table 1: Sub Base Strength Requirements Source: About Civil (2014) 8.0 Conclusions From the discussions in the report, a number of conclusions can be drawn based on the outcome of the fieldwork, aimed at prospecting the alternative route from Auckland to Hamilton. In the first place, it can be concluded that there is much justification for the proposed project to take place. This is because even though there are visible challenges with construction due to the sensitive environment of most of the sections and spots, the completion of the project can guarantee the needed easing in traffic expected. This is because much of areas to be included are currently secluded from human activity and abode. Meanwhile, the problem with the current State Highway network is not because the engineering work was not done well but because of artificial traffic situations created as a result of congestion. Any form of decongestion will therefore come as a solution to the problem. Again, it can be concluded the field engineers to be engaged in the construction must be very particular about the need to addressing the identified challenges ahead of commencement of work. This is because a refusal to do this could cause possible delays emanating from the need to deal with sudden and unplanned geological and geotechnical challenges. References About Civil (2014). Typical Road Structure Cross Section - Road Cross Section Details. Retrieved June 8, 2014 from http://www.aboutcivil.org/road-structure-cross-section.html BirdLife International. (2012). Important Bird Areas factsheet: Gannet Island. Auckland Regional Council. 8(2) 44-69 Butchers A. G (2009). Young New Zealand, Dunedin: Coulls Somerville Wilkie Ltd. Cardno, C. (2008). "Infrastructure: New Report Examines the Potential of Public-Private Partnerships for Transportation Infrastructure". Civil Engineering 78 (11) 56-85 ec-3geo (2014). Size and Extent of the Muriwai Coastal Environment. Retrieved June 8, 2014 from http://ec-3geo.wikispaces.com/S%26E+of+MCE [June 8, 2014] Ewen C., Bruce H. and Graeme M. (2007). A Field Guide to Auckland: Exploring the Regions Natural and Historic Heritage, Auckland: Godwit Publishing Ltd Given, L. M. (2008). The Sage encyclopedia of qualitative research methods. Los Angeles: Sage Publications. Koduah I (2009). "Army of fish to battle nasty weed". Auckland Regional Council. 5(3) 64-89 Power C and Elliott J (2006). "Cohort profile: 1958 British Cohort Study". International Journal of Epidemiology 35 (1): 34–41. Pratt, Ciara (13 January 2013). "Waitakere Ranges Sanctuary To Re-Introduce Kiwi". Western Leader (Stuff.co.nz). Retrieved 4 June 2014. Raglan Surfing School (2014). Map of Raglan. Retrieved June 8, 2014 from http://www.raglan.net.nz/about-raglan/map-of-raglan/ [June 8, 2014] Wises (2014). Directions from Auckland to Hamilton. Retrieved June 8, 2014from http://www.wises.co.nz/d/11/auckland/hamilton/#c/-37.318946/175.01774/8/ [June 8, 2014] Read More