海事工程挖泥船浚填作業工期影響因素及因應策略

Abstract

國內海事工程挖泥船浚填作業之施工環境多變與複雜性，常使工期難以掌握，由於 海上施工存在諸多不確定性之因素，因此在專案工程預估工期時，必須確認可工作天 數，但工期的影響，常隨著挖區作業環境與選用船機的不同而改變，使業者極易誤判情 勢，導致船機毀損停工待修，而影響後續工程之施工。 有鑑於此，本研究針對海事工程挖泥船浚填作業部分，藉由文獻回顧、過去挖泥工 程之實際案例、及20 年以上工程經驗專家訪談等方法，來分析探討可能影響工期之因 素，並進ㄧ步研擬其因應策略，目的為當有業者標到新工程時，可提供施工作業之參考 依據，讓工程管理者依據工程性質及施工條件，能正確估算出可工作天數及排除可能延 誤工期之障礙，使工程能如期順利完工。 經由研究結果，海事工程挖泥作業依挖區可分為港內作業及外海作業，工期影響兩 相比較明顯為外海作業大於港內作業，而工期影響因素依影響程度及機率可分為：氣象 及海象因素、挖區沉積物因素、作業船機因素，排泥管因素等4 大母因素及颱風、東北 季風、土質太黏、水下障礙物、船機老舊、超時限作業、排泥管老舊破損、飄失及沉入 等8 子因素。

Due to the varieties and complexities of dredging environment on domestic marine construction projects, the duration is frequently beyond control. Those uncertainties existing in marine construction lead to the necessity that when estimating duration, the workable days have to be ensured. However, the impact arising from duration often varies with the dredging environment and choice of dredging equipments, which easily results in the contractors’ misjudgments on the overall project such as the machinery breakdown, damage and suspending for repairs which in turn impact the operation of follow-up construction. In light of the above, this study, focusing on dredging operation of marine construction project, is to analyze and assess the liable factors affecting project duration through looking back relevant papers, practical case study of past dredging projects and interviews with professionals having more than 20 years in the said fields, which in turn may work out the countermeasures. The purpose is to provide the contractors with references for project execution, which would let project managers, according to the project nature and dredging conditions, estimate the workable days and preclude the possible factors delaying duration which in turn may complete the project smoothly and on schedule. As per the study, in terms of dredging area, marine dredging engineering is to be classified into in-harbor and offshore operation. Comparing between them, project duration is to be largely impacted by the latter than the former,The factors affecting project duration, in terms of extent of impact and probability, can be categorized into four major elements inclusive of weather and sea state, deposit in dredging area, condition of the dredger and discharge pipeline, which can further be divided into eight sub-elements including typhoon, monsoon, cohesive soil, underwater obstruction, over-time operation, and damage, drifting-away and sinking of discharge pipeline.