The existence of multiple optimum solutions in project Time-Cost Tradeoff (TCT) optimization has not been seriously researched, while the demand on computing time and resources considering project network models of practical size has not been benchmarked. To a certain degree, this has accounted for (1) the lack of commercial software in the market to enable TCT optimization in project management and (2) the absence of applications of TCT optimization in practice. This research proposes a streamlined TCT optimization methodology to generate the first order derivative function of project direct cost against project duration and identify the quantity and position of minimum solution(s) of total project cost. An Excel-based program was prototyped to facilitate validation and computing performance benchmarking using (1) “textbook” examples found in the literature and (2) simulated “test-bed” projects with practical complexity. In conclusion, this research opens the window of opportunity for implementing TCT optimization in practice.

项目时间成本权衡（TCT）优化中存在多个最优解的问题尚未得到认真研究，考虑到实际规模的项目网络模型对计算时间和资源的需求也没有进行基准测试。这在一定程度上解释了（1）市场上缺乏能够在项目管理中实现 TCT 优化的商业软件；（2）缺乏 TCT 优化在实践中的应用。本研究提出了一种简化的 TCT 优化方法，以生成项目直接成本对项目持续时间的一阶导数函数，并确定项目总成本的最小解决方案的数量和位置。使用 (1) 文献中的“教科书”示例和 (2) 具有实际复杂性的模拟“试验台”项目，对基于 Excel 的程序进行了原型设计，以促进验证和计算性能基准测试。总之，这项研究为在实践中实施 TCT 优化打开了机会之窗。