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Deep reinforcement learning-based critical element identification and demolition planning of frame structures

Shaojun ZHU; Makoto OHSAKI; Kazuki HAYASHI; Shaohan ZONG; Xiaonong GUO

《结构与土木工程前沿（英文）》 2022年第16卷第11期页码 1397-1414 doi: 10.1007/s11709-022-0860-y

摘要： This paper proposes a framework for critical element identification and demolition planning of frame structures. Innovative quantitative indices considering the severity of the ultimate collapse scenario are proposed using reinforcement learning and graph embedding. The action is defined as removing an element, and the state is described by integrating the joint and element features into a comprehensive feature vector for each element. By establishing the policy network, the agent outputs the Q value for each action after observing the state. Through numerical examples, it is confirmed that the trained agent can provide an accurate estimation of the Q values, and handle problems with different action spaces owing to utilization of graph embedding. Besides, different behaviors can be learned by varying hyperparameters in the reward function. By comparing the proposed method and the conventional sensitivity index-based methods, it is demonstrated that the computational cost is considerably reduced because the reinforcement learning model is trained offline. Besides, it is proved that the Q values produced by the reinforcement learning agent can make up for the deficiencies of existing indices, and can be directly used as the quantitative index for the decision-making for determining the most expected collapse scenario, i.e., the sequence of element removals.

关键词： progressive collapse alternate load path demolition planning reinforcement learning graph embedding

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CAS and ABM-based Demolition Waste Management Research in the AEC Industry

Zhi-kun Ding,Yi-fei Wang,Jin-chuang Wu

《工程管理前沿（英文）》 2016年第3卷第1期页码 18-23 doi: 10.15302/J-FEM-2016004

摘要： With the increase of the urban population and the rapid development of urbanization in China, a large number of old buildings will be demolished and produce a huge amount of waste. Currently the recycling ratio of old building materials is very low, which results in the problems of resource waste and environment pollution. This greatly challenges urban sustainable development. With respect to the continual growth of demolition waste quantities, it is urgent to research how to implement effective management of demolition wastes by focusing on the demolition agents’ behavior. Based on the theory of complexity, this paper analyzes the demolition waste management from the perspective of complex adaptive system. Taking into account the “green” demolition (building dismantling) and conventional demolition (building demolished) methods, the agent-based modeling method with Repast Simphony platform is applied to simulate interactions between demolition agents. The longitudinal trend of demolition waste quantities is forecasted.

关键词： demolition waste complexity science agent-based modeling

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三峡升船机贝雷架安装与拆除技术

刘勇,陈建峡

《中国工程科学》 2013年第15卷第9期页码 77-82

摘要：

三峡升船机塔柱横梁贝雷架支撑体系的安装与拆除属于高空立体交叉作业，而且施工场地狭窄、施工强度大，贝雷架的安装与拆除所受到的施工干扰大，是三峡升船机塔柱施工中的难题之一。本文通过对贝雷架施工作业环境的系统分析，根据不同部位的特点与要求，制定了有针对性的包括施工设备布置、吊装单元划分、吊点设置、各部位拆除方案在内的塔柱横梁贝雷架安装及拆除施工技术体系。该技术体系在三峡升船机贝雷架安装及拆除工程中得到顺利实施，塔柱横梁贝雷架支撑系统的施工进度、施工成本及施工安全均实现了良好的效果，表明该技术方案合理可靠。本文中贝雷架的安装与拆除施工技术体系可为类似条件下的贝雷架安装和拆除施工提供参考借鉴。

关键词：升船机贝雷架安装拆除三峡工程

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The use of fine portions from construction and demolition waste for expansive soil stabilization: A review

Mgboawaji Claude UJILE; Samuel Jonah ABBEY

《结构与土木工程前沿（英文）》 2022年第16卷第7期页码 803-816 doi: 10.1007/s11709-022-0835-z

摘要： Construction and demolition waste (CDW) are the largest waste products in the world today and competes as a viable recycled additive material in place of natural aggregates. Due to the increase in compressive strength of different mix proportions of CDW, it is also considered for reuse in concrete and subbase construction. This study shows the effect of CDW in expansive soil stabilization. The chemical and mechanical properties of these materials have shown that they are capable of developing compressive strength properties for replacement of cement with significant reduction in carbon emission. The inherent compositional properties of recycled CDW compared in this review suggests that CDW have good filler properties in highly expansive soils. Mixtures of crushed brick and recycled aggregates characterised based on chemical properties of different replacement ratios suggests that CDW of good-quality aggregates reduces swell potential of expansive soils and increased mechanical strength in pavement construction.

关键词： mixed fine portions construction and demolition waste expansive soil soil stabilization

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拆除爆破数值模拟研究进展

谢先启,刘军,贾永胜,孙金山

《中国工程科学》 2014年第16卷第11期页码 20-27

摘要：

评述了数值模拟技术在拆除爆破中应用的重要性，回顾了拆除爆破数值模拟的主要方法，论述了各种方法的优缺点。结合工程应用实例介绍了笔者及团队研发的离散元框架内的网格实体模型。分析了当前拆除爆破数值模拟技术存在的主要问题，对拆除爆破数值模拟技术的进一步发展进行了展望。

关键词：拆除爆破数值模拟离散元网格实体模型

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混凝土控制拆除施工技术及其在丹江口大坝加高工程中的综合应用

周厚贵

《中国工程科学》 2009年第11卷第2期页码 17-21

摘要：

混凝土控制拆除是水电工程续建、扩建、再建项目施工中的重点与难点问题之一。通过系统分析混凝土控制拆除的技术要求，总结了混凝土控制拆除施工常用方法的优点、适用条件和实施要点，建立了混凝土控制拆除施工方法选择标准体系。同时，将该体系应用于南水北调中线丹江口大坝加高工程的施工实践中，各项控制拆除工作实施效果良好。建立的混凝土控制拆除施工方法选择标准体系和丹江口大坝加高工程中的典型实例可供类似工程借鉴参考。

关键词：混凝土拆除控制拆除施工技术丹江口大坝

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Greenhouse gas emissions during co-composting of cattle feedlot manure with construction and demolition

Xiying Hao, Francis J. Larney

《环境科学与工程前沿（英文）》 2017年第11卷第3期 doi: 10.1007/s11783-017-0955-1

摘要： Manure management strategies should reflect current animal feeding practices and encourage recycling of organic waste to help protect our environment. This research investigated greenhouse gas (GHG) emissions during cattle manure stockpiling or composting with and without construction and demolition (C&D) waste. Manure was collected from cattle fed a typical finishing diet (CK manure) and from cattle on diets which included 30% dried distillers grains with solubles (DG manure). The CK and DG manures were co-composted with (4:1) C&D waste (treatments: CK_CD DG_CD), composted alone (treatments: CK and DG) in 13 m bins or stockpiled without C&D waste (treatments: CK_ST and DG_ST) for 99 days. Manure type (CK vs. DG manure) had no effect on GHG emissions over the 99 day manure composting or stockpiling. Composting with C&D waste produced similar CO emissions, about double that from manure stockpiling (7.0 kgC·m ). In contrast, CH emissions were reduced by the inclusion of C&D waste (64 gC·m with C&D vs. 244 gC·m without C&D) while the manure stockpile emitted the greatest amount of CH (464 gC·m ). Additionally, only 0.48% of C was emitted in CH form with C&D waste, compared to 1.68% when composting without C&D waste and 7.00% when cattle manure was stockpiled. The N O emissions (12.4 to 18.0 gN·m ) were similar across all treatments. The lower CH emissions with C&D waste are beneficial in reducing overall GHG emissions from manure composting, while reducing the amount of material entering landfills.

关键词： Livestock manure greenhouse gas flux straw bale compost bin N₂O CH₄ CO₂

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城市高架桥爆破拆除起爆网路可靠性研究

吴新霞,赵根,谢先启

《中国工程科学》 2014年第16卷第11期页码 72-77

摘要：

本文针对城市高架桥爆破拆除的长距离、长延时，目前只能采用非电起爆网路进行起爆的现状，研究了多发并联起爆网路的接力点雷管延期特性，提出了并联后的接力点起爆时间期望值的简易计算公式。针对不同规模的非电起爆网路提出了相应的可靠度标准，研发了既可保证高架桥倾倒过程不发生侧翻又能提高接力点起爆可靠度并可无限分段的复式交叉接力起爆网路，并推导了其起爆可靠度计算公式。相关成果为高架桥拆除爆破起爆网路设计提供了科学依据。

关键词：高架桥拆除爆破起爆网路可靠性

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Pollution of hazardous substances in industrial construction and demolition wastes and their multi-path

Sheng Huang, Xin Zhao, Yanqiu Sun, Jianli Ma, Xiaofeng Gao, Tian Xie, Dongsheng Xu, Yi Yu, Youcai Zhao

《环境科学与工程前沿（英文）》 2017年第11卷第1期 doi: 10.1007/s11783-017-0901-2

摘要： Pollution pattern of metals and organic pesticide in demolition waste is studied. Organophosphorus pesticide can be everlasting on surface of demolition waste. Leaching potential of pollutants from simulated and onsite waste varies spatially. Direct oral and dermal ingestion, leaching potential into water exceed the limit. Implications for demolition waste management in industrial plants are proposed. Exploration of heavy metals and organic pollutants, their leaching capacity along with health and environmental risks in contaminated industrial construction and demolition waste (ICDW) within a pesticide manufacturing plant were investigated. A maximum content of 90.8 mg·kg Cd was found present in the wastes, which might originate from phosphorus rocks and industrial sulfuric acid used in pesticide production processes. An average concentration of 979.8 mg·kg dichlorovos and other 11 organophosphorus pesticide were also detected. Relatively high leaching rates of around 4.14‰ were obtained from laboratory simulated ICDW using both glacial acetic acid- sodium hydroxide and deionized water. Pesticide pollutants had the strongest tendency to retaining on dry bricks (leaching rate 1.68‰) compared to mortar-coatings, etc. due to their different physical characteristics and octanol-water partioning coefficient. Mobility of pesticide from on-site ICDW by water was spatially correlated to waste types, process sections and human activities, with a flux of leaching rate between 5.9‰ to 27.4%. Risk-based corrective action (RBCA) model was used to simulate the risk of contaminated ICDW debris randomly scattered. Oral and dermal ingestion amount by local workers was 9.8 × 10 and 1.9 × 10 mg·(kg·d) , respectively. Potential leaching risk to aquatic systems exceeded the limit for nearly 75% waste. Environmental and health risk exceedance was found in most ICDW, while the risk value of the most severely contaminated brick waste was 660 times beyond critical level. Implications for waste management involving construction and deconstruction work, waste transferring and regulation supplying were also provided.

关键词： Industrial demolition wastes Heavy metals Pesticides Leaching characteristics Risk assessment Waste management

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城市立交桥爆破拆除塌落振动的测量与分析

胡进军,杨永强,管英珺

《中国工程科学》 2014年第16卷第11期页码 90-95

摘要：

为分析城市立交桥爆破拆除时结构构件塌落造成的地面振动的特征，介绍了某城市典型立交桥的爆破拆除中地面振动的测量方法，并基于观测点实测数据对地面振动的加速度峰值、频率和持时进行了分析。分析结果表明：塌落造成的竖向地振动幅值比水平分量大，但是其随着距离增大迅速衰减，因此在距离塌落处较近的区域应该考虑竖向地振动的影响；桥梁结构多次连续塌落会导致出现地面振动的叠加，采取减隔振措施可以降低加速度峰值，同时也会使得加速度的峰值频率降低、持时增加；爆破和塌落振动并未对保留桥梁结构造成损伤，说明爆破拆除是一种安全、高效的拆除方法。

关键词：爆破拆除城市立交桥塌落地面振动加速度

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大直径盾构负环管片拆除及隧道换装技术

翟志国,黄学军,杨志永

《中国工程科学》 2010年第12卷第12期页码 83-88

摘要：

通过对北京铁路地下直径线2标工程的研究，确定在刀盘改造期间进行负环管片拆除的一系列工作，重点如部分反力架的拆除方法、负环管片的详细拆除方法以及拆除反力架后临时支撑的架设方法，同时就泥水盾构隧道的换装技术进行了叙述，最终在7 d之内成功拆除了7环负环管片，节约了工期，保证了后继施工的材料运输速度。

关键词：大直径盾构负环管片拆除隧道换装

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城市爆破拆除的粉尘预测和降尘措施

郑炳旭,魏晓林

《中国工程科学》 2002年第4卷第8期页码 69-73

摘要：

提出了正态分布无边界扩散模式粉尘浓度预测法，介绍了广州体育馆爆破拆除时的降尘措施，即清理积尘、楼面蓄水、预湿墙体、屋面敷水袋、建筑外设高压管网喷水、搭设防尘排栅和直升机投水弹并产生下向风流等综合防尘技术，实施后减轻了粉尘危害。

关键词：控爆拆除粉尘预测和控制高压喷水降尘环保

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Family planning technical services in China

Shang-Chun WU

《医学前沿（英文）》 2010年第4卷第3期页码 285-289 doi: 10.1007/s11684-010-0097-3

摘要： Family planning is a basic state policy in China. Its aim is to control population growth and to enhance population quality. Technical services are the key measures for implementing the family planning policy. In order to ensure that people use safe, effective, and appropriate contraceptive methods based on the government’s commitment, China has established countrywide family planning service networks down to the township level. The people can access various and convenient contraceptive services. In urban areas, all contraceptive services are free. The contraceptive prevalence rate in 2007 was 84.6%, the percentage of intrauterine device (IUD) was 52.3%, that of female sterilization was 32.3%, and that of vasectomy was 6.1%. This means that more than 90% of married childbearing couples were using long-term contraceptives. At the same time, the government gives priority to supporting research on contraceptive technology. Studies’ results have provided scientific evidence for development, introduction, and expansion of contraceptive methods, and also for establishment and revision of the technical guidelines. Great efforts have been made in promoting “human-oriented and client-centered” services during the recent ten years. Remarkable success has been achieved in improving the quality of technical services.

关键词： family planning contraceptive method service delivery

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Enterprise-wide optimization of integrated planning and scheduling for refinery-petrochemical complex

《化学科学与工程前沿（英文）》 2023年第17卷第10期页码 1516-1532 doi: 10.1007/s11705-022-2283-7

摘要： This paper focuses on the integrated problem of long-term planning and short-term scheduling in a large-scale refinery-petrochemical complex, and considers the overall manufacturing process from the upstream refinery to the downstream petrochemical site. Different time scales are incorporated from the planning and scheduling subproblems. At the end of each discrete time period, additional constraints are imposed to ensure material balance between different time scales. Discrete time representation is applied to the planning subproblem, while continuous time is applied to the scheduling of ethylene cracking and polymerization processes in the petrochemical site. An enterprise-wide mathematical model is formulated through mixed integer nonlinear programming. To solve the problem efficiently, a heuristic algorithm combined with a convolutional neural network (CNN), is proposed. Binary variables are used as the CNN input, leading to the integration of a data-driven approach and classical optimization by which a heuristic algorithm is established. The results do not only illustrate the detailed operations in a refinery and petrochemical complex under planning and scheduling, but also confirm the high efficiency of the proposed algorithm for solving large-scale problems.

关键词： planning scheduling refinery-petrochemical convolutional neural network heuristic algorithm

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Development and challenges of planning and scheduling for petroleum and petrochemical production

Fupei LI, Minglei YANG, Wenli DU, Xin DAI

《工程管理前沿（英文）》 2020年第7卷第3期页码 373-383 doi: 10.1007/s42524-020-0123-3

摘要： Production planning and scheduling are becoming the core of production management, which support the decision of a petrochemical company. The optimization of production planning and scheduling is attempted by every refinery because it gains additional profit and stabilizes the daily production. The optimization problem considered in industry and academic research is of different levels of realism and complexity, thus increasing the gap. Operation research with mathematical programming is a conventional approach used to address the planning and scheduling problem. Additionally, modeling the processes, objectives, and constraints and developing the optimization algorithms are significant for industry and research. This paper introduces the perspective of production planning and scheduling from the development viewpoint.

关键词： planning and scheduling optimization modeling