子费用模糊估算的水电工程总造价概率估计

根据工程系统的可分解性，将水电工程总体造价分解成若干个子工程造价。用模糊数学贴近度原理，建立子工程造价的模糊估算模型；运用主观估计法，估计出各个子工程造价随机变化的期望值和方差。然后依据概率论多元随机变量理论，推出水电工程总体造价概率分布的期望值和方差，并确定了造价随机变化的概率分布关系曲线。该估计方法客观、全面地反映了工程造价的实际随机变化特性。

Probability estimation of total construction cost for hydropower project with fuzzy estimation of subconstruction cost

Estimation of construction cost is the important link in the earlier stage of the hydropower engineering. It is influenced by a lot of uncertainty factors with the randomness. In this paper, the construction cost is decomposed into several subconstruction costs according to the decomposability of system. The fuzzy estimation model of subconstruction cost is established by employing the near-degree thoery in fuzzy mathematics. Based on the subjective estimation method, value of expectation and variance of several subconstruction were determined. Then, expected value and variance of total construction cost of hydropower engineering were deduced by using theory of multivariate stochastic variable and the relation curve was defined between cost and probatility. This estimation method objectively reflects the realistic change characteristic of construction cost.