Geotechnical Engineering Issue: Mishary - Assignment Example

Geotechnical Engineering Issue-Mishary. Student’s Name Institution Geomechanics in excavation and foundation works. The investigation/ review topic. The excavation of construction phase helps lay the structural foundations. However, various soil geotechnical soil properties influence the excavation and foundation work and the ultimate strength of the structure. The soil/rock properties influence the extent and type of excavation required for the specific structures. Different properties also affect the mechanisms of landslide disasters in foundation and excavation works. The outline of the project report. Geomechanics in excavation and foundation works. The soil properties that influence the excavation work and the foundation systems include structure, texture, porosity and permeability. Additionally, other soil properties that influence the excavation and the foundation system construction include liquid limit, plastic limit, soil densities and shrinkage characteristics. These factors affect the lifespan of the foundation systems as well as the types of columns suitable for the specific types of foundations. Responsibilities of a geotechnical engineer. In foundation and excavation as well as building construction, the responsibilities of the geotechnical engineer include assistance of the displacement and the resettlement activities associated with the project. Besides, he/she should engage in the development of the sustainable engineering designs. Moreover, he/she acts as a player in the environmental management. Principles of sustainable design and development. The principles of design and development for use in foundation and excavation work include designing with an aim to create durable structures with manageable lifespan. Besides, designing and development with the aim to create a sustainable project should also have plans for the structural afterlife. Moreover, the design/development practice needs to embrace the product flexibility as well as agile processes. Suggested investigation areas. The suggested areas of research are the classification of the types of foundations according to the soil properties. Foundation system of Prima Pearl Tower (ground improvement, land development, land reclamation work) Prima Pearl Tower was completed in June 2014, and the foundation work faced such challenges as high water table and difficult soil strata. The ground improvement of the foundation system included the construction of the retaining walls as well as the use of jet grout columns. Mechanism/cause of landslides in excavation works and foundation systems. The cause of landslides in excavation and foundation systems include water, seismic waves and mechanical vibrations caused by the excavators. The occurrence of landslides in excavation and foundation works is more probable in sloppy areas. Mechanisms of failure of foundation systems. Failure of the foundation systems is caused by high rates of evaporation, low soil drainage, poor ground preparation as well as poor soil compaction. It can also result from leaky plumbing. Failure of foundations happens due to foundation settlement, cracks and gaps in the system. Remedies for foundation systems failures. The foundation failures can be remedied through watering, soil testing prior to foundation works, use of compressors to compact the soil. Besides, it can be avoided by the employment of the standard plumbing practices. Investigation report. Geomechanics in excavation and foundation works. Excavation is one of the initial phases of both surfaces and underground structures. Excavation work varies with the type of oil or rock and their properties. Such geotechnical soil properties that influence excavation include structure, texture, porosity and permeability. Extra-fine soil structure characterizes the clay soils, and the excavation work for that class of soil includes drainage excavation before setting up a foundation system of the work (Handy & Spangler, 2007). Soil structure influences the amount of empty spaces in the soil and thus such aspects as drainage, moisture content, and aeration. These aspects are important in engineering work as well as structure foundation systems. Soil permeability particularly affects the decisions abound the foundation systems because of the need to put up waterproofing mechanisms in highly permeable soils in foundation works as well as raising the structural columns (Hicher, 2012). On the other hand, the porosity of the soil influences the soil mass’ strength. However, the porosity of the soil is a product of the soil structure, texture and organic matter content. The index properties of the soil that influence excavation works and foundation systems include liquid limit, plastic limit, soil densities and shrinkage characteristics. These properties, also known as Atterberg Limits, are assessable in the laboratories for the fine-grained soil classes (Hicher, 2012). Other geotechnical aspects that influence foundation systems and excavation works include friction angles of the soil heaps and soil cohesion and have effects on the safety recommendations to be followed in civil engineering works (Handy & Spangler, 2007). Foundation systems affect the size, as well as the lifespan of a structure and engineers, has a requirement to determine adequately the geotechnical as well as geomechanical soil properties before putting up various structures (Preview: Geomechanics and Tunnelling 4/2015, 2015). Responsibilities of a geotechnical engineer. Geotechnical engineers have a wide variety of social, cultural, global and environmental responsibilities surrounding the excavation as well as foundation works. Structures that place a need for displacement of persons from their settlements also place a need for resettlement of the same individuals (Lancellotta, 2009). Displacement of individuals to pave the way for structural developments cause a set of social disruptions. The engineering community has a responsibility to facilitate the resettlement of these individuals where necessary. If the displaced individuals depend on the soil for specific cultural practices, the engineering community need to come up with a list of soil properties that is favourable to the communities’ cultural practices as well as the influence of such aspects on the favourite resettlement locations. The most significant global responsibilities of the geotechnical engineers in the excavation and the foundation systems include the sustainable design and development of the structures to increase their lifespan. In this face, the engineers need to interpret the research finding to come up with suitable recommendations for the specific structures (Lancellotta, 2009). Besides, they need to be part of the research undertakings to investigate the suitable options of sustainable structural design and development. From the environmental management point of view, the engineer has a responsibility to report as well as make recommendations about the findings of project’s environmental investigations. This responsibility is shared with the project’s environmental managers. Besides investigating the environmental impacts, the geotechnical engineers also have the responsibility to collaborate with other experts to provide remedies to the identified environmental issues. Additionally, these engineers are involved in drafting the standard operating procedures for use in the work environment in order to prevent environmental degradation. Furthermore, they also provide the necessary technical support to the environmental litigation and remediation projects, such as regulatory applicability and remediation system design (Lancellotta, 2009). Principles of sustainable design and development. The traditionally developed and designed engineering works do not have effective approaches to addressing all facets of the built industry needs. However, most of the engineering projects developed towards and in the 21st century have consideration of the principles of sustainable development (American Society of Civil Engineers, 2004). One of the sustainable design and development approaches necessary for the excavation and foundation works is the guiding objective to establish a durable structure rather than an immortal one. A durable structure lives to the targeted commercial life without causing any overwhelming set of environmental problems like bioaccumulation and solid waste disposal. If a structure is designed to have an immortal lifespan, it can result in the accumulation of undesirable environmental hazards. A durable structure allows the employment of the minimal techniques for maintenance as well as the introduction of minimal material to support the foundation system (American Society of Civil Engineers, 2004). The second sustainable engineering principle applicable in the excavation works and foundation systems are the design for the commercial afterlife of the structure. Since built environment and engineering practices are always changing, a point is reached where the commercial suitability of the structure ends because of stylistic or technological obsolescence (National Concrete Masonry Association, 2010). At the end of the commercial afterlife of the structure, it is important to have a sound plan to reuse the remnants of the obsolete structure to enable sustainable development. Such a plan reduce wastage of the remaining valuable and functional component of the structure. The third principle of sustainable engineering applicable to geotechnical engineers in excavation works and foundation systems is the product flexibility and the process agility to meet the need as well as minimize the excess (American Society of Civil Engineers, 2004). Besides, this principle helps design with a consideration of the worst case scenarios, modulate the performance with an aim to address the unrealistic/extreme conditions likely to be faced in the project. Suggested investigation areas. Foundation systems’ success depends largely on the soil types, which influences the type of the foundation constructed for different structures. That notwithstanding, most of the research work is diverted towards materials and construction methods of the foundation systems. It is, therefore, recommendable to commit professional resources in the investigation of the soil in relationship to the types of foundation. The recommendable subsurface research includes the subsoil conditions, number and location of borings and the suitable properties for specific buildings. Besides, it is worthy researching the surface soil properties and classify them in terms of in terms of susceptibility to slides and water rise above the water table (American Society of Civil Engineers, 2004). Finally, it is recommendable to establish a link between such soil characteristics as compressibility and plasticity to the suitability of different types of foundation systems. Foundation system of Prima Pearl Tower (ground improvement, land development, land reclamation work) The technical completion date of Prima Pearl Tower was June 30th, 2014. Prima Pearl seats in the precincts of Melbourne, Victoria. This building has 72 levels and is 254 meters high. The foundation system’s work and the geotechnical aspects of the building were contracted to Frankipile Australia (Chapman & Stillman, 2014). This building was constructed in a challenging site, with high water table and poor soil properties. The soil composed of a large deposit of soft clay above a layer of basalt, stiff clay, sand and weathered siltstone at the bedrock. For the contractor to lay the foundation, a 10-meter deep excavation below the water table was required to be propped by piles of the lift core of the structure. 22No 1800mm diameter bored piles of 40m length were used. In order to avoid the collapsing of holes, the 1800mm span bored piles were penetrated under polymer (Chapman & Stillman, 2014). Additionally, self-compacting tremie and concrete techniques were applied to complete the piles. For the constructor to facilitate the construction of the lift core on the project, the jet grout columns (installed to as lateral base slab) was introduced, helping support the secant load wall cofferdam. At the depth of 20-22m, a 1-2m thick stratum of Weathered Basalt placed a challenge but heavy duty augers and Fundex 3500 were used to penetrate the material. Other ground improvement methods used for the development of the Prima Pearl Tower’s foundation system is the construction of the retaining walls within the foundation to allow the inclusion of the basements, tanks, swimming pools and retaining walls (Chapman & Stillman, 2014). Mechanism/cause of landslides in excavation works and foundation systems. Landslides are potential risks in excavation and foundation systems’ work especially if the structure is to be constructed in sloppy locations (Canuti & Sassa, 2013). Landslides result in the movement of rocks and/or soil due to gravitational pull affecting the natural slopes. The risk of landslides n foundation works as well as the excavations increases above normal in steep locations with loose soil, seismic zones, intense weathering and high rainfall, amongst others. As a result, landslides occur because of the imbalanced relationship between the external and internal forces acting on the ground in such a way that the destabilising forces out-power the resistant or stabilizing forces. In excavation and foundation works, landslides happen in several different mechanisms. If the foundation system is to be erected in a rainfall-rich environment, the excavation work and water will work together to cause landslides (Canuti & Sassa, 2013). Excavation work in wet soil creates soil instability because of the already existing low friction causing a downhill sliding of debris. If the soil has fine grains, a small amount of water increases stability and resistance to landslides. However, high water content creates destabilization and a resultant landslide. On the other hand, if the foundation system is to be constructed in seismic zones, excavation works increase the risks of landslides. Earthquakes cause the vibration of the earth’s crust, and if the crust already has weaknesses from excavations any, the friction disruptions can cause a landslide can occur (Canuti & Sassa, 2013). Moreover, landslide can be caused by the vibrations emanating from the excavators. Some excavation equipment cause high levels of vibrations capable of causing local destabilization of the crust. As a result, landslides can take place, and the impact would depend on the depth and scale excavation. Such landslide activities associated with excavation include sinkage and subsidence. Sinkage happens in the underground cavities often without any surface effect. In foundation systems work, sinkage happens if the excavations include underground tunnels. On the other hand, the subsidence events involve the slow sinkage of soils because of the declining of the water table as a result of the excavation activities. Mechanisms of failure of foundation systems. A foundation system is designed to support the surface structures, and it is a requirement to meet all the laid standards before announcing the completion of the foundation; otherwise it will fail to meet the design expectations (National Concrete Masonry Association, 2010). There are several causes of foundation failure and if remedied in a timely manner success is achieved. One of the many causes of failure in foundations systems of buildings is evaporation. Evaporation is a result of hot and dry conditions that cause soil particle to retract from the foundation. Such retraction causes the imbalance of moisture of the foundation and cracks may appear across the structure. Besides, if the period of dryness is extended, there is soil shrinkage beneath the foundation (National Concrete Masonry Association, 2010). As a result, gaps are created next to the foundation. Foundation system failure can also result from plumbing leaks. Leaky plumbing causes the excessive water and the associated erosion of the soil that is supporting the foundation. Besides, leaky plumbing also increases the soil’s moisture content, and the result may include foundation movement as well as the foundation settlement. However, the degree of foundation movement is dependent on the soil density as well as the soil type. Foundation failure can also result from the soil drainage. If the soil is less well-drained, there is an associated increase in the moisture content as well as the resultant soil erosion or consolidation. Additionally, excessive soil moisture may also cause settlement or upheaval. Poorly drained soil can also cause soil oversaturation and instability around the foundation systems (Brown, 2001). Foundation failure due to poor drainage is irreversible hence the need to act proactively towards soil drainage. Foundation failure can also happen as a result of poor ground preparation. Cut-fill practices that are widely used when building structures can result in poorly compacted soil underlying the foundation (National Concrete Masonry Association, 2010). The failure associated with poor soil compaction is caused by low soil density and soft soil. Besides, the failure can also result from the water that seeps below the foundation because of lack of proper diversion of water from the structure. If the building site is poorly prepared, the soil is less stable and does not have capabilities to stand any unexpected movements leading to foundation settlement. Remedies for foundation systems failures. The causes of foundation system failure are widespread creating a requirement for the geotechnical engineers to have remedial measures on standby. The major cause of foundation systems failure is evaporation (Brown, 2001). Evaporation due to extreme environmental conditions can be difficult to handle. However, some practices can be applied to create moisture balance in the soil and reduce soil shrinkage beneath the foundation. One of the widely applied practices is periodic watering of the foundation system during the curing phase. It is recommended to assess the soil for such properties as porosity and water retention to determine the amount necessary to uphold the soil moisture at the optimum levels to avoid moisture over-saturation. After establishing the water retention properties of the soil, a watering program should be raised in order to reduce the creation of gaps next to the foundation (Brown, 2001). Nevertheless, building a structure in a soil that is capable of supporting the optimum moisture levels is the ultimate solution to the evaporation problems in the foundation systems. The failure of the foundation systems because of the leaky plumbing can be mitigated through the use of technically high-quality plumbing techniques. Apart from using high-quality plumbing equipment, it is necessary to apply certified expertise. The plumbing crew need use the set standards to avoid leaky piping systems that can result in accumulation of water in the faulty areas. The pipes used in the plumbing activities should also be resistance to adverse conditions of the soil as well as have the high durability to support a long leak-free life of the piping system (National Concrete Masonry Association, 2010). On the other hand, the drainage causes of failure of the foundation systems can be remedied through drainage excavation especially if the structure borders a water stream. This practice reduces the moisture content of the soil surrounding the structure. Remedies to soil drainage need to be sought earlier than the commencement of the project because they are inapplicable if the structure has been erected. Soil drainage ensures that foundation system does not settle because of the soil over-saturation (Brown, 2001). Foundation failures due to poor preparation of the building site can be remedied through adequate soil stabilization before the construction of the structure. Soil stabilization is achieved through compaction before using the appropriate compressors. Finally, poor preparation of the ground can be remedied through soil grading to determine its structural properties and help establish how to divert water from the structure. References. American Society of Civil Engineers. (2004). Sustainable engineering practice: An introduction. Reston, VA: American Society of Civil Engineers. Brown, R. W. (2001). Practical foundation engineering handbook. New York: McGraw-Hill. Canuti, P., & Sassa, K. (2013). Landslide science and practice: Volume 6. (Landslide science and practice.) Berlin: Springer. Chapman, H., & Stillman, J. (2014). Melbourne then and now. Handy, R. L., & Spangler, M. G. (2007). Geotechnical engineering: Soil and foundation principles and practice. New York, NY: Mcgraw-Hill. Hicher, P.-Y. (2012). Multiscale geomechanics: From soil to engineering projects. London: ISTE. Lancellotta, R. (2009). Geotechnical engineering. London: Taylor & Francis. National Concrete Masonry Association. (2010). Design manual for segmental retaining walls. Herndon, Va: National Concrete Masonry Association. Preview: Geomechanics and Tunnelling 4/2015. (August 01, 2015). Geomechanics and Tunnelling, 8, 4, 368. Read More

The ground improvement of the foundation system included the construction of the retaining walls as well as the use of jet grout columns. Mechanism/cause of landslides in excavation works and foundation systems. The cause of landslides in excavation and foundation systems include water, seismic waves and mechanical vibrations caused by the excavators. The occurrence of landslides in excavation and foundation works is more probable in sloppy areas. Mechanisms of failure of foundation systems. Failure of the foundation systems is caused by high rates of evaporation, low soil drainage, poor ground preparation as well as poor soil compaction.

It can also result from leaky plumbing. Failure of foundations happens due to foundation settlement, cracks and gaps in the system. Remedies for foundation systems failures. The foundation failures can be remedied through watering, soil testing prior to foundation works, use of compressors to compact the soil. Besides, it can be avoided by the employment of the standard plumbing practices. Investigation report. Geomechanics in excavation and foundation works. Excavation is one of the initial phases of both surfaces and underground structures.

Excavation work varies with the type of oil or rock and their properties. Such geotechnical soil properties that influence excavation include structure, texture, porosity and permeability. Extra-fine soil structure characterizes the clay soils, and the excavation work for that class of soil includes drainage excavation before setting up a foundation system of the work (Handy & Spangler, 2007). Soil structure influences the amount of empty spaces in the soil and thus such aspects as drainage, moisture content, and aeration.

These aspects are important in engineering work as well as structure foundation systems. Soil permeability particularly affects the decisions abound the foundation systems because of the need to put up waterproofing mechanisms in highly permeable soils in foundation works as well as raising the structural columns (Hicher, 2012). On the other hand, the porosity of the soil influences the soil mass’ strength. However, the porosity of the soil is a product of the soil structure, texture and organic matter content.

The index properties of the soil that influence excavation works and foundation systems include liquid limit, plastic limit, soil densities and shrinkage characteristics. These properties, also known as Atterberg Limits, are assessable in the laboratories for the fine-grained soil classes (Hicher, 2012). Other geotechnical aspects that influence foundation systems and excavation works include friction angles of the soil heaps and soil cohesion and have effects on the safety recommendations to be followed in civil engineering works (Handy & Spangler, 2007).

Foundation systems affect the size, as well as the lifespan of a structure and engineers, has a requirement to determine adequately the geotechnical as well as geomechanical soil properties before putting up various structures (Preview: Geomechanics and Tunnelling 4/2015, 2015). Responsibilities of a geotechnical engineer. Geotechnical engineers have a wide variety of social, cultural, global and environmental responsibilities surrounding the excavation as well as foundation works. Structures that place a need for displacement of persons from their settlements also place a need for resettlement of the same individuals (Lancellotta, 2009).

Displacement of individuals to pave the way for structural developments cause a set of social disruptions. The engineering community has a responsibility to facilitate the resettlement of these individuals where necessary. If the displaced individuals depend on the soil for specific cultural practices, the engineering community need to come up with a list of soil properties that is favourable to the communities’ cultural practices as well as the influence of such aspects on the favourite resettlement locations.

The most significant global responsibilities of the geotechnical engineers in the excavation and the foundation systems include the sustainable design and development of the structures to increase their lifespan.

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