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Dive into the research topics where Keith R. Molenaar is active.

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Featured researches published by Keith R. Molenaar.


Journal of Management in Engineering | 2011

Selection of Project Delivery Method in Transit: Drivers and Objectives

Ali Touran; Douglas D. Gransberg; Keith R. Molenaar; Kamran Ghavamifar

This paper describes the results of research on alternative project delivery methods in transit projects in the United States. The research, sponsored by the Transit Cooperative Research Program, aimed to identify those factors that drive the decision in the choice of project delivery method. A rigorous case study analysis based on on-site structured interviews with the directors of several transit projects was used to identify decision drivers and the rationale behind the delivery method selection decision in transit agencies. The nine case studies conducted in this research represent a cross section of delivery methods, including design-bid-build/multiprime, construction manager-at-risk, design/build, and design/build-operate-maintain. The interviewees agreed that the use of alternative delivery methods have resulted in savings in schedule and cost for transit agencies. The research also found that achieving aggressive schedule compression is the most influential factor when selecting alternative delive...


Construction Management and Economics | 2006

Strategies for overlapping dependent design activities

Susan M. Bogus; Keith R. Molenaar; James E. Diekmann

Overlapping activities that are traditionally performed in a sequential manner can significantly reduce project delivery times. Overlapping, however, should be approached in a systematic manner to reduce the costs and risks. Information gathered from sector‐based case studies and from the manufacturing domain suggest a formalised framework for identifying overlapping opportunities and strategies can be successfully implemented for infrastructure projects. This framework considers activity characteristics, such as evolution of upstream information and sensitivity of downstream activities to changes in upstream information, to identify appropriate overlapping strategies. Overlapping strategies, such as early freezing of design criteria, overdesign, and early release of preliminary information, are selected based on activity characteristics. These strategies operate either by speeding up the evolution of upstream information or by reducing the sensitivity of downstream activities. By aligning overlapping strategies with activity characteristics, project managers can make better decisions on when and how much to overlap sequential activities to reduce overall project delivery time.


Journal of Construction Engineering and Management-asce | 2010

Integrated Framework for Quantifying and Predicting Weather-Related Highway Construction Delays

Somkiat Apipattanavis; Kevin Sabol; Keith R. Molenaar; Balaji Rajagopalan; Yunping Xi; Ben Blackard; Shekhar S. Patil

Constant exposure to the environment makes highway construction highly dependent on weather. However, highway construction contracts are often unclear about the potential influence of weather-related delays on highway construction project schedules. There is a need to discourage litigation arising from weather-related delays by including in contracts a reasonable number of nonwork days as a consequence of adverse weather and providing an equitable criteria for the course of action when the predictions in the contracts turn out to be inaccurate. To address this need, an integrated framework consisting of the following two key components is proposed: (1) identification of attributes of weather that cause construction delays and (2) generation of synthetic weather sequences using a stochastic weather generator to quantify and provide probabilistic forecasts of weather threshold values. The utility of this framework is demonstrated through its application to construction work on a project in Texas. The use of probabilistic forecast of construction delay attributes provided by a semiparametric weather generator in this research is an example of interdisciplinary study to help address this problem. The result of the research is better decision support for agencies who wish to author contracts that more equitably allow for the influence of weather during construction.


Journal of Construction Engineering and Management-asce | 2011

Simulation of Overlapping Design Activities in Concurrent Engineering

Susan M. Bogus; James E. Diekmann; Keith R. Molenaar; Christofer M. Harper; S. Patil; J. S. Lee

Concurrent engineering is the process of reducing the total project delivery time by overlapping activities that normally occur sequentially. The benefits are a shortening of delivery time and a possible reduction in overall costs. However, there are potential risks to overlapping dependent activities. The interaction between an upstream activity and a downstream activity relies on how information evolves in the upstream activity and how sensitive the downstream activity is to that changing information. This implies that if an upstream activity is slow to evolve information and a downstream activity is highly sensitive to changing information, the risk in overlapping these activities will be higher than activities that are fast to evolve and not as sensitive to changing information. The risk can manifest in rework, or reperforming some aspect of the downstream activity because of the evolution of the upstream activity and the amount of overlapping used. This research developed computer simulation models to better understand the potential risk of rework. The simulation models allow for overlapping different types of slow- and fast-evolving upstream activities with high- and low-sensitivity downstream activities using overdesign and early release strategies and different amounts of overlapping. The overall findings show that simulations of overlapping activities yield a reliable approach to modeling concurrent engineering activities. The simulations provide information on the probability of rework based on the different combinations of evolution, sensitivity, overlapping strategy, and the percent amount of overlapping used between the upstream and downstream activity. The use of computer simulations and modeling of overlapping activities therefore allows engineers and managers to understand the potential risks and what strategies to apply when utilizing concurrent engineering on a project.


Journal of Construction Engineering and Management-asce | 2012

Determining the Appropriate Proportion of Owner-Provided Design in Design-Build Contracts: Content Analysis Approach

Bo Xia; Albert P.C. Chan; Keith R. Molenaar; Martin Skitmore

The Request For Proposal (RFP) with the design‐build (DB) procurement arrangement is a document in which an owner develops his requirements and conveys the project scope to DB contractors. Owners should provide an appropriate level of design in DB RFPs to adequately describe their requirements without compromising the prospects for innovation. This paper examines and compares the different levels of owner‐provided design in DB RFPs by the content analysis of 84 requests for RFPs for public DB projects advertised between 2000 and 2010 with an aggregate contract value of over


TCRP Report | 2009

A Guidebook for the Evaluation of Project Delivery Methods

Ali Touran; Douglas D. Gransberg; Keith R. Molenaar; Kamran Ghavamifar; D J Mason; Lee A Fithian

5.4 billion. A statistical analysis was also conducted in order to explore the relationship between the proportion of owner‐provided design and other project information, including project type, advertisement time, project size, contractor selection method, procurement process and contract type. The results show that the majority (64.8%) of the RFPs provide less than 10% of the owner‐provided design. The owner‐provided design proportion has a significant association with project type, project size, contractor selection method and contract type. In addition, owners are generally providing less design in recent years than hitherto. The research findings also provide owners with perspectives to determine the appropriate level of owner‐provided design in DB RFPs.


Journal of Management in Engineering | 2013

Enterprise Risk Management Strategies for State Departments of Transportation

Matthew R. Hallowell; Keith R. Molenaar; Bernard R. Fortunato

This guidebook describes various project delivery methods for major transit capital projects. The guidebook also includes an evaluation of the impacts, advantages, and disadvantages of including operations and maintenance as a component of a contract for a project delivery method. The project delivery methods discussed are design-bid-build (DBB), construction manager at risk (CMR), design-build (DB), and design-build-operate-maintain (DBOM). The guidebook offers a three-tiered project delivery selection framework that may be used by owners of transit projects to evaluate the pros and cons of each delivery method and select the most appropriate method for their project. Tier 1 is a qualitative approach that allows the user to document the advantages and disadvantages of each competing delivery method. The user can then review the results of this analysis and select the best delivery method. If, at the conclusion of this analysis, a clear option does not emerge, the user then moves on to Tier 2. Tier 2 is a weighted-matrix approach that allows the user to quantify the effectiveness of competing delivery methods and select the approach that receives the highest score. The third tier uses principles of risk analysis to evaluate delivery methods. The selection framework may also be useful as a means to document the decision in the form of a Project Delivery Decision Report. The guidebook will be helpful to transit general managers, policy-makers, procurement officers, planners, and consultants in evaluating and selecting the appropriate project delivery method for major transit capital projects.


Journal of Construction Engineering and Management-asce | 2011

Risk Planning and Management for the Panama Canal Expansion Program

Luis F. Alarcón; David B. Ashley; Angelique Sucre de Hanily; Keith R. Molenaar; Ricardo Ungo

AbstractThe leaders of DOTs and other public agencies that build and operate capital facilities manage a multitude of human, technological, political, technical, and natural resources in an environment that is fraught with uncertainty. To ensure success, these agencies must be able to manage risks at multiple levels. Although there is a great deal of literature and research relating to project risk management for public projects, there has yet to be a study that evaluates enterprise risk management (ERM) for DOTs. The objectives of this study are to describe the state-of-practice with respect to risk management in state DOTs and to identify executive strategies that may be useful to DOT leadership for enterprise-wide risk management. This paper presents the results of a comprehensive survey with responses from 43 of the 52 United States DOTs that identify and describe the currently implemented ERM strategies. The findings from the literature and survey were validated through interviews with top DOT manage...


Public Works Management & Policy | 2010

Contract Payment Provisions and Project Performance: An Analysis of Municipal Water and Wastewater Facilities

Susan M. Bogus; Jennifer S. Shane; Keith R. Molenaar

In April 2006, the Panama Canal Authority formally proposed a major expansion of the canal to increase its capacity and make it more productive, safe, and efficient. This proposal included cost and schedule estimates for completing the expansion and was supported overwhelmingly by the citizens of Panama in an October 2006 public referendum. Given the conceptual level of design at the time of the proposal and the inherent uncertainty in a project of this magnitude at the early stages of engineering, a comprehensive risk analysis was performed to develop a contingency model for the total expansion program cost and schedule. This contingency model is based on a Monte Carlo simulation of the cost and schedule estimates, taking into account the most significant risks identified for the project. The resulting model provides contingency assessments for duration and total cost and sensitivity analysis of the risks; it also allows for multiple scenario planning and ultimately supports overall risk management. This paper presents a project case study that focuses on the contingency model development and the resulting risk management and contingency resolution processes.


Journal of Management in Engineering | 2013

Analysis of Selection Criteria for Design-Builders through the Analysis of Requests for Proposal

Bo Xia; Albert P.C. Chan; Jian Zuo; Keith R. Molenaar

In a continued effort to provide water and wastewater facilities, owners have been using a variety of contract pricing methods for the construction of new facilities. Increasing use of cost-plus-fee with a guaranteed maximum price (GMP) contract payment provisions along with the more traditional lump sum contract payment provisions has created a need to measure the effectiveness of these contract pricing methods. Through a detailed survey of public water and wastewater facility owners, performance data were collected to compare project performance based on schedule and cost growth measures. The results of this study indicate that contracts using cost-plus-fee with a GMP contract pricing provisions are more likely to have no schedule or cost growth as compared to projects with lump-sum provisions. Overall, the results of this study provide new data for water and wastewater projects that can be used by owners to improve future project performance.

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Susan M. Bogus

University of New Mexico

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James E. Diekmann

University of Colorado Boulder

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Amy Javernick-Will

University of Colorado Boulder

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Matthew R. Hallowell

University of Colorado Boulder

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Ali Touran

Northeastern University

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Arthur L. C. Antoine

University of Colorado Boulder

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