计划风险管理中英文对照外文翻译文献

计划风险管理中英文对照外文翻译文献

(文档含英文原文和中文翻译)

原文：

Schedule Risk Management INTRODUCTION

Schedule risks are both threats and opportunities to the success of a project. Threats tend to reduce the success of meeting the project goals and opportunities tend to increase the success. Risk management is the process of identifying, analyzing, qualifying and quantifying the risks, and developing a plan to deal with them. This is routinely done during baseline schedule development as well as during schedule updates. Implementation of risk

management starts with early planning in both budgetary cost estimating and preliminary master scheduling in order to determine budgets and schedules with a comfortable level of confidence in the completion date and final cost. While there are entire volumes addressing risk in construction projects, it is important to note that the issue of time-related risk has not been universally incorporated into planning. Assessing cost risk is more intuitive, and very often addressed through the use of heuristics, so it has become more of a standard of the industry than time-related risk management. Most estimators will automatically add a contingency to

a cost estimate to cover the risk of performance based on the type of project and circumstances pertaining to the undertaking of the project. Estimators estimate this contingency using their own rules of thum

b developed over years of estimating as well as estimate ingmanuals，such as Means’ Cost Data or Cost Works. However, when it comes to

developing the critical path method (CPM) schedules, risk management is often overlooked or underestimated.

The purpose of this chapter is to provide an overview of risk management and the assessment process as well as best practices for incorporation of risk management into CPM schedule development and maintenance. For more detailed information about schedule risk, the reader should refer to risk management books, particularly those that focus on project management. One of the best resources available is David Hulett’s new book, Practical Schedule

Risk Analysis.

Any risk management program starts with a good and accurate CPM schedule, created through the use of best practices and checked for quality, reasonableness, and appropriateness of the network model. Without a well-designed and developed CPM baseline schedule, a risk management process will not be effective. The risk analysis depends upon accurate and consistent calculations of the network logic, the appropriateness of the sequencing and phasing, and a reasonable approach to estimating activity durations.

Most CPM schedules are not adjusted for risk but rather are developed as if there were one right answer for the schedule’s numerical data. Generally, activity durations are established by calculation of the quantity of work represented by an activity divided by the production rate, or by sheer ‘‘gut feeling’’ of the project manager or crew leader. This production rate is normally established by the contractor’s historical records or an estimating system, such as Means’, that provides an accurate data base of average production rates. Once those durations are calculated, they are often used as deterministic values, which assumes that the durations are accurate and unlikely to change. This assumption ignores the fact that the schedule is attempting to predict how long it will take to complete an activity at some unknown time in the future,

using an unknown crew composition, with variable experience, and working