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Different Roads to the Same Destination?

Description

Sustainable Materials Management and Circular Economy are both frameworks for considering the way we interact with the world's resources. Different organizations and institutions across the world have adopted one philosophy or the other. To some, there seems to be little

Sustainable Materials Management and Circular Economy are both frameworks for considering the way we interact with the world's resources. Different organizations and institutions across the world have adopted one philosophy or the other. To some, there seems to be little overlap of the two, and to others, they are perceived as being interchangeable. This paper evaluates Sustainable Materials Management (SMM) and Circular Economy (CE) individually and in comparison to see how truly different these frameworks are from one another. This comparison is then extended into a theoretical walk-through of an SMM treatment of concrete pavement in contrast with a CE treatment. With concrete being a ubiquitous in the world's buildings and roads, as well as being a major constituent of Construction & Demolition waste generated, its analysis is applicable to a significant portion of the world's material flow. The ultimate test of differentiation between SMM and CE would ask: 1) If SMM principles guided action, would the outcomes be aligned with or at odds with CE principles? and conversely 2) If CE principles guided action, would the outcomes be aligned with or at odds with SMM principles? Using concrete pavement as an example, this paper seeks to determine whether or not Sustainable Materials Management and Circular Economy are simply different roads leading to the same destination.

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Date Created
2017-05

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Analysis of the state of practice and best practices for alternative project delivery methods in the transportation design and construction industry

Description

Alternative Project Delivery Methods (APDMs), namely Design Build (DB) and Construction Manager at Risk (CMAR), grew out of the need to find a more efficient project delivery approach than the traditional Design Bid Build (DBB) form of delivery. After decades

Alternative Project Delivery Methods (APDMs), namely Design Build (DB) and Construction Manager at Risk (CMAR), grew out of the need to find a more efficient project delivery approach than the traditional Design Bid Build (DBB) form of delivery. After decades of extensive APDM use, there have been many studies focused on the use of APDMs and project outcomes. Few of these studies have reached a level of statistical significance to make conclusive observations about APDMs. This research effort completes a comprehensive study for use in the horizontal transportation construction market, providing a better basis for decisions on project delivery method selection, improving understanding of best practices for APDM use, and reporting outcomes from the largest collection of APDM project data to date. The study is the result of an online survey of project owners and design teams from 17 states representing 83 projects nationally. Project data collected represents almost six billion US dollars. The study performs an analysis of the transportation APDM market and answers questions dealing with national APDM usage, motivators for APDM selection, the relation of APDM to pre-construction services, and the use of industry best practices. Top motivators for delivery method selection: the project schedule or the urgency of the project, the ability to predict and control cost, and finding the best method to allocate risk, as well as other factors were identified and analyzed. Analysis of project data was used to compare to commonly held assumptions about the project delivery methods, confirming some assumptions and refuting others. Project data showed that APDM projects had the lowest overall cost growth. DB projects had higher schedule growth. CMAR projects had low design schedule growth but high construction schedule growth. DBB showed very little schedule growth and the highest cost growth of the delivery methods studied. Best practices in project delivery were studied: team alignment, front end planning, and risk assessment were identified as practices most critical to project success. The study contributes and improves on existing research on APDM project selection and outcomes and fills many of the gaps in research identified by previous research efforts and industry leaders.

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Agent

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Date Created
2014

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Performance of the construction manager at risk (CMAR) delivery method applied to pipeline construction projects

Description

Much of the water and wastewater lines in the United States are nearing the end of their useful life. A significant reinvestment is needed in the upcoming decades to replace or rehabilitate the water and wastewater infrastructure. Currently, the traditional

Much of the water and wastewater lines in the United States are nearing the end of their useful life. A significant reinvestment is needed in the upcoming decades to replace or rehabilitate the water and wastewater infrastructure. Currently, the traditional method for delivering water and wastewater pipeline engineering and construction projects is design-bid-build (DBB). The traditional DBB delivery system is a sequential low-integration process and can lead to inefficiencies and adverse relationships between stakeholders. Alternative project delivery methods (APDM) such as Construction Manager at Risk (CMAR) have been introduced to increase stakeholder integration and ultimately enhance project performance. CMAR project performance impacts have been studied in the horizontal and vertical construction industries. However, the performance of CMAR projects in the pipeline engineering and construction industry has not been quantitatively studied.

The dissertation fills this gap in knowledge by performing the first quantitative analysis of CMAR performance on pipeline engineering and construction projects. This study’s two research objectives are:

(1) Develop a CMAR baseline of commonly measured project performance metrics

(2) Statistically compare the cost and schedule performance of CMAR to that of the traditional DBB delivery method

A thorough literature review led to the development of a data collection survey used in conjunction with structured interviews to gather qualitative and quantitative performance data from 66 completed water and wastewater pipeline projects. Performance data analysis was conducted to provide performance benchmarks for CMAR projects and to compare the performance of CMAR and DBB.

This study provides the first CMAR performance benchmark for pipeline engineering and construction projects. The results span across seven metrics in four performance areas (cost, schedule, project change, and communication). Pipeline projects delivered using CMAR have a median cost and schedule growth of -5% and 5.10%, respectively. These results are significantly improved from DBB baseline performance shown in other industries. To verify this, a statistical analysis was done to compare the cost and schedule performance of CMAR to similar DBB pipeline projects. The results show that CMAR pipeline projects are being delivered with 6.5% less cost growth and with 12.5% less schedule growth than similar DBB projects, providing owners with increased certainty when delivering their pipeline projects.

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Agent

Created

Date Created
2015

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Quantifying the Impact of Circular Economy Applied to the Built Environment: A Study of Construction and Demolition Waste to Identify Leverage Points

Description

The built environment is responsible for a significant portion of global waste generation.

Construction and demolition (C&D) waste requires significant landfill areas and costs

billions of dollars. New business models that reduce this waste may prove to be financially

beneficial and generally more

The built environment is responsible for a significant portion of global waste generation.

Construction and demolition (C&D) waste requires significant landfill areas and costs

billions of dollars. New business models that reduce this waste may prove to be financially

beneficial and generally more sustainable. One such model is referred to as the “Circular

Economy” (CE), which promotes the efficient use of materials to minimize waste

generation and raw material consumption. CE is achieved by maximizing the life of

materials and components and by reclaiming the typically wasted value at the end of their

life. This thesis identifies the potential opportunities for using CE in the built environment.

It first calculates the magnitude of C&D waste and its main streams, highlights the top

C&D materials based on weight and value using data from various regions, identifies the

top C&D materials’ current recycling and reuse rates, and finally estimates a potential

financial benefit of $3.7 billion from redirecting C&D waste using the CE concept in the

United States.

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Agent

Created

Date Created
2019