RMC – Public & Private Participation (original) (raw)
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Ready Mixed Concrete for Quality Assurance & Sustainable Construction
In the wake of progress in infrastructure and industry in the country, the focus needs to be kept on good quality, durable, speedy and environment-friendly construction for sustainable growth and development. Civil Engineering community’s responsibility towards society concerns safe and enduring infrastructure at minimized life-cycle cost without severely affecting environment. Achievement of overall economy in terms of life cycle cost of structure and sustainability of construction by adopting environment-friendly techniques is the only alternative suitable for modern construction. To achieve this traditional methods of construction will not be sufficient and new technologies especially Ready-Mixed concrete (RMC) will need to be adopted.
PERSPECTIVE ON USE OF READY-MIXED CONCRETE (RMC) IN MUMBAI INFRASTRUCTURE
In the wake of progress in infrastructure and industry in Mumbai and rest of the country, the focus needs to be kept on good quality, durable, speedy and environment-friendly construction for sustainable growth and development. Civil Engineering community's responsibility towards society concerns safe and enduring infrastructure at minimized life-cycle cost without severely affecting environment. Achievement of overall economy in terms reduced recurring maintenance of structures and sustainability of construction by adopting environment-friendly techniques is the only alternative suitable for modern construction. To achieve this traditional methods of construction will not be sufficient and new technologies especially Ready-Mixed concrete (RMC) will need to be adopted. Ready-Mixed concrete is concrete manufactured at a central location in highly sophisticated and rigorously controlled plants. In conventional site mix, concreting is done at the mercy of gangs, who manipulate the cement, water and other ingredients of concrete. On the contrary concrete is an engineering material and use of proper design and technical approach can improve performance and optimize the costs. In ready mixed concrete, design as well as the proportions are accurately controlled leading to overall better quality of concrete structures. Durability of structure is improved due to high level of quality control, thereby leading to reduction in lifecycle cost and maintenance free structures. This kind of increase can have a major impact on national economy and optimised utilisation of resources like limestone, energy and industrial by-products. Also, it is an environment friendly technology as it substantially reduces air pollution arising at sites because of handling of cement, aggregates etc. at sites. In view of the above advantages, the rest of the world has adopted RMC as the appropriate technology for construction. There is a need in India as well to consciously promote this industry so as to benefit the development of public and private infrastructure in sustainable manner. In order to achieve speedy, sustainable and economical construction, we as a country should look forward to reviewing our strategies and learn from available experiences abroad to promote RMC and allied industries like bulk cement etc.
In today's business environment, the coordination of just-in-time (JIT) production and transportation is one of the most challenging aspects to ensure timely delivery of materials to distributed customers. Several risk factors make JIT supply chains more vulnerable and methods for analysing and understanding supply chain risks are still needed in construction. This paper describes the implementation of failure mode, effects, and criticality analysis (FMECA) tool and discrete event simulation to assess supply chain risks, identify vulnerabilities, and measure the impact of disruptions of a ready-mix concrete supply chain. Interviews with concrete batch plant managers and current demand, production, and delivery performance data served as input for analysis. We provided a systematic method that can be used by concrete suppliers to improve planning and delivery of ready-mix concrete. Different mitigation strategies were suggested based on our findings.
Due to its evolving technology and dynamic nature, a sizeable segment of the world’s construction market that used to partly rely on traditional site-mixed concrete (SMC) had almost completely shifted to ready-mixed concrete (RMC) several decades ago in the developed countries. Likewise, this targeted trend has been observed in developing countries. The Egyptian residential sector has also adopted some corrective changes in this direction in the last decade. Nevertheless, the vast majority of builders in the Egyptian market have continued to oppose to this global paradigm shift. The observed “cultural” resistance to change seems to be chiefly driven by the difference in the unit price of SMC and RMC, overlooking the latter’s superior characteristics and its added values that fundamentally overweigh this apparent difference in cost. This survey-based study aims at promoting the use of RMC over SMC for construction of new residential communities in Egypt. A mixed (qualitative and quan...
Ready-Mixed Concrete for Concrete Roads
The use of concrete in constructing roads and other pavements is growing steadily in recent times. In India the last decade has seen emergence of Ready-Mixed concrete (RMC) in leading cities. There has been a general increase in awareness of civil engineers regarding superiority of using modern technology in construction projects. There has been an increase in trend toward specifying RMC in big projects including concrete roads. Prevailing circumstances have led to the use of RMC at various roadwork sites especially in cities like Mumbai. This technical paper aims at presenting a practical outlook towards intricacies involved and observations made at such sites. The data referred to, in this write-up comes from concrete of M35 grade supplied by UNITECH PREFAB LTD, to some contractors of Municipal Corporation of Greater Mumbai (MCGM) for their CC-roads at different locations across Mumbai during the period September'97 to June'03.
Cellular Concrete & its facets of application in Civil Engineering
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