基于工期可靠性分析的装配式施工场地布置动态优化研究

曹君怡

摘 要

装配式建筑作为建筑工业化发展的产物，近些年在国家政策大力支持下，新开工面积不断增加，在新建建筑中的占比不断增大。在装配式建筑施工过程中，施工场地布置合理性对于工程建设目标影响显著。因此本文以装配式建筑施工场地布置作为研究对象，重点分析预制构件堆场的动态布置，并基于系统布局设计理论和精益建造思想建立综合关系值和场地覆盖面积目标函数，构建装配式施工场地布置多目标动态规划模型，使用差分进化算法（DE）对模型进行求解分析。同时使用蒙特卡罗抽样方法建立工期可靠性分析模型，与动态规划模型进行集成，实现基于工期可靠性分析的场地布置动态优化，主要研究内容如下：

（1）建立装配式建筑施工场地布置多目标动态规划模型。以预制构件堆场的动态布置为核心，建立堆场随时间变化的数量、尺寸及坐标的数学模型，结合场地布置相关约束，依据SLP理论和精益建造思想，以综合关系值最大和场地覆盖面积最小为目标，选用差分进化算法对模型进行优化求解，得到以天为单位动态变化，满足多目标的装配式施工场地布置方案；

（2）建立工期可靠性分析模型，对可靠性进行评价，根据可靠性结果对场地布置方案进行优化。在计划工期下场地布置动态规划的基础上，对变化工期进行可靠性研究，使用蒙特卡罗抽样方法建立工期可靠性分析模型，选择合适的优化路径对进度计划进行优化，使其满足可靠性。将优化结果与场地布置动态规划模型进行集成，实现场地布置基于工期可靠性分析的动态优化，最后利用BIM实现布置方案可视化。

本文对装配式施工场地的动态变化和工期的不确定性进行分析，提出基于工期性分析的装配式施工场地布置动态优化模型，通过合理的场地布置，减少二次搬运，降低管理成本，提高场地利用率，实现了装配式建筑施工现场的高水平管理。

关键词：施工现场管理；场地动态布置；工期可靠性；装配式建筑；方案优化

Abstract

As the product of the industrial development of traditional buildings, prefabricated buildings have been strongly supported by national policies in recent years. The area of new prefabricated buildings is increasing continuously, and its proportion in the buildings is increasing. In the process of prefabricated building construction, the rationality of construction site layout has a significant impact on the project construction goals. Therefore, this thesis took the prefabricated building site layout as the research object, focused on analyzing the dynamic layout of the prefabricated component yard, established comprehensive relationship value and site coverage area  objective function based on Systematic Layout Planning theory and the Lean Construction theory, and constructed a multi-objective dynamic programming model for the prefabricated site layout, using the differential evolution algorithm (DE) to solve and analyze. At the same time, use the Monte Carlo sampling method to construct the reliability analysis model of the construction period and integrate the reliability analysis model with the dynamic programming model to realize the optimization of the site layout based on the reliability analysis of the construction period. The main research contents are as follows:

(1) A multi-objective dynamic programming model for prefabricated building construction site layout was established. In the model, the dynamic changes of the prefabricated component yard were taken as the core, and a mathematical model of the quantity, size and coordinates of the yard changing with time was established. According to SLP theory and Lean Construction theory, the objective function of maximizing the comprehensive relationship value and minimizing the site coverage area were established, and the multi-objective Differential Evolution algorithm was used to optimize. Then the prefabricated construction site layout planning changing by day was obtained to meet the multiple objectives;

(2) A reliability analysis model for the construction period was established and its result was used to optimize the site layout planning. Based on the dynamic planning of multi-objective site layout under the planned construction period, the reliability of variable duration was studied. The calculation model of construction period reliability was established based on Monte Carlo sampling method. Then the schedule was optimized by appropriate optimization path to improve the probability of reliable duration. The optimization results were integrated with the site layout planning model to realize the optimization of the site layout based on the reliability of construction period. Finally, BIM was used to realize the visualization of the plan.

By analyzing the dynamic changes of prefabricated construction site layout and the uncertainty of construction period, the thesis proposes a multi-objective dynamic optimization model for prefabricated building construction site layout based on the reliability of construction period. Through reasonable site layout, secondary handling is reduced, management costs are reduced, site utilization is improved, and high-level management of the prefabricated building construction site is achieved.

Key words: Construction Site Management; Site Dynamic Layout; Reliability of Construction Period; Prefabricated Buildings; Scheme Optimization