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The impact of using Polymer Modified Bitumen in Asphalt mixes

Paper Abstract:

The economic growth of any country relies on many factors, such as natural resources, technology, manpower, regulations, and infrastructure. Infrastructure is essential for country development. Road networks are part of the infrastructure of any country. The presence of a reliable road network will facilitate the shipping of goods, which will save time and money and contribute to economic growth. A road network is considered reliable when it reduces the journey time, provides the best routes, properly covers a country or area, reduces the delay of public transportation, contributes to economic growth, and ensures a smooth ride. Building a high-quality road pavement that meets the needs of road users and ensures smooth riding requires good planning, design, and construction of the pavement. The construction of durable pavement can be attained through the collaboration of reliable design, selecting high-quality and suitable raw materials, appropriate asphalt mix design, and the implementation of proper construction methods in compliance with local and international standards. The need for a pavement with a longer service life that can bear high traffic loads with fewer repair requirements has become essential nowadays. Therefore, polymer-modified bitumen has been used to improve the asphalt mix properties and produce a pavement with a higher service load and higher durability. This paper will briefly review flexible pavement and focus on reviewing the different aspects of polymer-modified bitumen (PMB). Moreover, this paper will compare the properties of PMB with ordinary bitumen. The properties of the bitumen and asphalt mixes furnished in this paper have been determined by conducting the required tests at qualified labs. All test procedures and methods are in compliance with international standards.

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Quality management at construction projects: Case study of a stormwater network project

This paper summarizes the common procedures and measures used on construction sites to control the quality of executed works. The presence and implementation of a quality management system will ensure that the construction meets client requirements. The presence of a quality management system alone is not sufficient; the correct and strict implementation of a quality management system is substantial. The implementation of a quality management system in construction requires the collaboration of the client, contractor, and engineer (a client representative). The practical side of quality management systems is discussed in this paper, and the construction of a stormwater network in the UAE is taken as an example and case study. This paper is mainly focused on quality in construction projects. Controlling the quality of construction projects will pass through various stages. And it is not limited to construction activities. The control of construction activities is not sufficient to produce a meticulous final product. A quality system should be implemented in every aspect of a project, such as the project document, materials, testing, construction process, etc. Involving a case study in this paper will assist in a better understanding of the quality management system at construction projects. Moreover, some examples of quality violations and the actions taken to correct the breach will be furnished as part of this study. The stormwater network was constructed as part of the development and construction of a new community. The stormwater network has a length of 22 km, and it involves the construction of all components of the stormwater network.

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Comparison between piles theoretical and actual settlements

This paper compares the actual settlement of the pile foundation with the anticipated theoretical settlement computed using various methods. The piles under investigation were constructed to support a bridge structure and they are cast-in-situ piles. The bridge structure is supported by three groups of piles with pile lengths ranging from 11 m to 14 m and a diameter of 1.20 m. Detailed geotechnical investigations were performed to determine the soil's mechanical and chemical properties. Moreover, four piles were loaded statically to verify the viability of the design. kentledge method for testing was used, the concrete block was used as a counterweight and the main load was generated by the use of Hydraulic jacks, the settlement of piles recorded for each load increment. Four strain gauges were used to record the settlement of piles. The estimation of pile foundation theoretical settlement is performed by the use of various equations suggested by each method. The soil parameters incorporated in these equations are taken from the geotechnical report. Three boreholes were drilled at three different locations to collect soil samples, both disturb and un-disturb samples collected at various depths. Then all the samples were collected and tested to determine soil classification and the important parameters and properties of soil and rock such as unconfined compressive strength, particle size distribution, etc. Therefore, the parameters used for determining pile theoretical settlement are considerably precise, reliable, and represent the site condition.

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Case study: Widening an existing bridge structure Challenges and solutions

This paper is a study that summarizes, the procedure used to increase the capacity of an existing concrete bridge in the UAE. Traffic congestion is a severe problem in modern life. Severe congestion can negatively impact the country's economy, environment, and the health of road commuters. The increase in trip duration due to traffic congestion will result in consuming more fuel which results in a higher cost of trip and more emissions which affect both the economy and the environment. Moreover, the road commuter will be traveling for a long time which can affect their sleeping hours and mental health. Constructing more roads, and bridges and encouraging people to use public transport are some of the measures taken to reduce traffic congestion. To evaluate the effectiveness of an existing highway, certain parameters such as traffic quantity, type of vehicles in the traffic stream, speed of traffic stream, and the density of traffic stream will be measured and assessed to determine the need for increasing the road capacity. This paper considers the structural part and challenges faced during the process of widening an existing bridge structure. The existing bridge under consideration is composed of two spans with a length of 33.10 m of each span, two abutments with pot bearing connection, a single monolithic pier, asphaltic plug expansion joint at abutments, voided post-tensioned concrete slab with concrete barriers. The decision was taken to widen the existing bridge to relieve the aggravated traffic jam problem. The development of residential areas nearby resulted in increasing the volume of traffic exceeding the existing road capacity. The new development proposal involves the construction of a completely new bridge with 4 lanes and the widening of the existing bridge. The final output is two bridges with 4 lanes in each direction.

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Mohammad
My name is Mohammad Hamdan, and I am a Civil/bridge Engineer with extensive professional background and experience in the field of construction. I have 10+ years of experience in the construction field. During my professional career, my emphasis has been placed on structural projects, mainly bridges, infrastructure and roads. Reading and practicing the design of structures is my passion.i was lucky to be a part of a big team that executed major highway interchanges. I believe in spreading the knowledge, thus, i compose these courses to share my experience and knowledge. My course focuses on the practical side of construction field. On other word, i am sharing some of what new engineers need to know about construction field. Beside working on construction field, i love writing some articles on my website ( curious civil engineer) Moreover, i wrote some engineering papers, you can check them  by searching my name on Google (Mohammad mamon Hamdan)