給排水系統利用建築資訊模型估算成本之實證研究

BIM Application for Quantity Take-off and Cost Estimation of Plumbing System in Buildings

林存甫(Chun-Fu Lin)

指導教授 ： 郭斯傑

國立臺灣大學/工學院/土木工程學研究所/碩士(2015年)

https://doi.org/10.6342/NTU.2015.00312

摘要

在營建工程中，機電工程錯綜複雜的管線往往造成彼此間或者與結構的衝突，為了避免此類衝突所導致的變更設計，業主漸漸會主動要求於營建工程使用建築資訊模型(以下簡稱BIM)，惟對於建築物機電工程設計單位而言，使用BIM的主要目的依舊是衝突檢討，學習與適應BIM技術勢必會造成營運成本的額外負擔，導致現階段機電設計單位主動使用BIM的意願並不高，數量與估價功能的發展相對更加受限。然而給排水系統之設計單位於編列預算時，部分會採取模糊的乙式計價，導致業主端因為不清楚詳細數量來源，所得到的資訊不透明。因此本研究以高雄市南部災害應變中心為案例，利用BIM軟體Revit 2013建構該建築主體結構以及其給排水系統模型，進而輸出更加明確給排水系統數量與金額，並進行差異分析與Revit軟體使用性探討。
本研究透過建立高雄市南部災害應變中心主體建築與給排水系統BIM模型，得以輸出更明確之給排水實體設備管線數量，消弭機電工程給排水部分過去採二維圖說設計所導致模糊乙式之計價項目，將逾兩百萬台幣之概估金額改為細估金額，使業主與施工單位更加瞭解數量與金額來源。根據本研究結果，認為BIM對給排水系統工程估價程度尚待發展，以本研究案例為例，尚有三分之一給排水系統金額無法藉由Revit 2013軟體輸出；數量輸出方面，BIM輸出給排水系統總金額為9,849,032元，較該範圍內原始發包金額(10,693,632)低，差距為844,600 (-8%)，其主要金額差異來源為管長與管另件 (消耗另料亦有連帶影響)，且模型輸出結果皆為低於招標金額，經過差異分析，本研究認為過去機電設計單位有過於高估金額之行為。

關鍵字

建築資訊模型 ； 給排水系統 ； 乙式 ； 估價 ； 另件

並列摘要

In civil construction, MEP (Mechanical, Electrical and Plumbing) engineering is the most complex one in buildings. In order to avoid conflicts and interference among MEP systems, many construction projects are in need of building information model (BIM), which is a 3D tool for diverse physical infrastructures planning and design. Despite the increasing requirements for BIM by owners of building construction, MEP designers are not willing to use BIM due to the expense and time spent on BIM technique adaption. Instead, most designers prefer to design MEP by 2D drafting and therefore estimate cost of MEP engineering in traditional way. However, part of traditional cost estimation of MEP engineering is rough approximation instead of detailed estimation, which makes the origin of cost invisible and inaccurate. The purpose of this research was to visualize and clearly estimate the indistinct budget items which traditional estimating methods are unable to calculate in detail, and verified the usability and accuracy of BIM QTO/cost estimation of the plumbing system.
By building the whole architecture model, structure and detailed plumbing components of a finished public office building, the study discovered that there was some overestimation of plumbing budgets by MEP designers, which could let MEP designers gain more invisible profit without owner’s detection. However, with a thorough inspection of the MEP families of BIM software, it was found in this study that some constraints on the BIM tool led to more than one-third of the overall plumbing budget still unable to be output by BIM. The BIM main software’s capability of quantity take-off and cost estimation on plumbing system hasn’t been fully developed.

並列關鍵字

BIM ； MEP ； plumbing ； QTO ； cost estimation

參考文獻

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