Tower crane path planning based on improved ant colony algorithm

In order to solve the problem of path planning of tower cranes,an improved ant colony algorithm was proposed.Firstly,the tower crane was simplified into a three-degree-of-freedom mechanical arm,and the D-H motion model was established to solve the forward and inverse kinematic equations.Secondly,the traditional ant colony algorithm was improved.The heuristic function was improved by introducing the distance between the optional nodes and the target point into the function.Then the transition probability was improved by introducing the security factor of surrounding points into the transition probability.In addition,the local path chunking strategy was used to optimize the local multi-inflection path and reduce the local redundant inflection points.Finally,according to the position of the hook,the kinematic inversion of the tower crane was carried out,and the variables of each joint were obtained.More specifically,compared with the traditional ant colony algorithm,the simulation results showed that improved ant colony algorithm converged faster,shortened the optimal path length,and optimized the path quality in the simple and complex environment.

Evaluation of Driver-Induced Human Errors in Smart Construction Tower Crane Operations Based on DEMATEL-ISM-MICMAC

With the advent of Industry 4.0, smart construction sites have seen significant development in China. However, accidents involving digitized tower cranes continue to be a persistent issue. Among the contributing factors, human unsafe behavior stands out as a primary cause for these incidents. This study aims to assess the human reliability of tower crane operations on smart construction sites. To proactively enhance safety measures, the research employs text mining techniques (TF-IDF-Truncated SVD-Complement NB) to identify patterns of human errors among tower crane operators. Building upon the SHEL model, the study categorizes behavioral factors affecting human reliability in the man-machine interface, leading to the establishment of the Performance Shaping Factors (PSFs) system. Furthermore, the research constructs an error impact indicator system for the intelligent construction site tower crane operator interface. Using the DEMATEL method, it analyzes the significance of various factors influencing human errors in tower crane operations. Additionally, the ISM-MICMAC method is applied to unveil the hierarchical relationships and driving-dependent connections among these influencing factors. The findings indicate that personal state, operating procedures, and physical environment directly impact human errors, while personal capability, technological environment, and one fundamental organizational management factor contribute indirectly. .

Research on the Three-dimensional Modeling and Optimization of a Virtual Tower Crane Based on 3DS Max, Solidworks and EON Professional

Three-dimensional modeling of virtual hoisting machinery is the critical works to structure the system of virtual construction, and the foundation to realize intelligent and interactive virtual hoisting. Aimed at enhancing the requests of image quality and stability of the virtual construction scene, taking a tower crane for example. We studied the technology of three-dimensional modeling and optimization of a virtual tower crane, and a method named two-stage model optimization was put forward. This depended on the modeling stage using Solidworks and 3DS Max and the performance optimization stage in EON. The practice of software development indicates that the proposed methods of three-dimensional modeling and optimization could satisfy the performance request of virtual construction system and be popularized to other virtual system.

An Intelligent System for Real-Time Condition Monitoring of Tower Cranes

Reliability and safety are major issues in tower crane applications. A new adaptive neurofuzzy system is developed in this work for real-time health condition monitoring of tower cranes, especially for hoist gearboxes. Vibration signals are measured using a wireless smart sensor system. Fault detection is performed gear-by-gear in the gearbox. A new diagnostic classifier is proposed to integrate strengths of several signal processing techniques for fault detection. A hybrid machine learning method is proposed to facilitate implementation and improve training convergence. The effectiveness of the developed monitoring system is verified by experimental tests.

Importance Ranking of Accident Factors of Construction Tower Crane by AHP Technique

In Korea construction industry, the increase of tower crane’s usage continuously and the accidents of tower crane are increasing simultaneously. But research on tower crane is insufficient for reducing the tower crane accident. This study aims to derive the importance ranking of accident factors of cab-control tower crane by AHP analysis. AHP survey was conducted on experts such as construction engineer, construction manager, safety engineer, and tower crane operator, who have more than 10-year career. The results of AHP analysis reveal that top ranking factor of cab-control tower crane’s accident is erection work. Therefore, the derived factors should be managed, and the priority measures taken for reducing the tower crane accidents according to the ranking of accident factors.

综合交通枢纽工程盖挖逆作法研究与应用

基于北京城市副中心站综合交通枢纽工程的特殊地理位置和地质条件,本项目采用盖挖逆作法进行地下建筑的施工。首先对地下结构工程的施工方法进行了概述,基于项目实际工程情况对盖挖逆作的施工重难点进行分析,确定了合理高效的盖挖逆作施工顺序;其次对盖挖逆作工程中的土方开挖技术、基坑降水施工技术、基坑监测技术等进行创新改进,提高了工程效率的同时保证了安全度。此外,针对盖挖逆作塔式起重机基础施工技术进行改进,采用钢管桩式混凝土承台塔式起重机基础。最后,在盖挖逆作技术基础上结合BIM和AR技术进行了创新应用,推动了盖挖逆作工程的现代化发展。

山区拱桥双层无缆塔缆索吊施工技术

平绵高速武都至九寨沟段尖山沟特大桥主桥为主跨220 m的上承式钢管混凝土拱桥,左、右幅分离式布置,两幅净间距30 m。大桥位于U形山谷,不具备支架法施工条件,拱肋采用缆索吊及扣挂法悬臂拼装,其它构件均采用缆索吊安装。从材料设备投入、吊装覆盖范围、施工进度及操作难度方面,对缆扣合建、缆扣分离和无缆塔缆索吊方案进行比选,推荐采用无缆塔缆索吊作为实施方案。在60 t主缆索吊上方设置1台15 t辅助工作缆索吊,形成双层无缆塔缆索吊系统,进行缆索吊锚碇构件运输安装;为节约缆索吊成本,利用桥位山体设置主索可横移锚碇,通过缆索吊主索横移实现单组主索横移分榀安装钢管拱肋。双层无缆塔缆索吊立体同步作业,提高了施工效率。

基于面向对象的塔机结构有限元建模方法研究

针对塔机结构有限元分析存在建模繁琐,模型重用性差,造成塔机结构设计周期长、成本高等问题,提出基于面向对象的塔机结构有限元建模方法。利用Abaqus的二次开发语言Python创建塔机部件类和装配类,先通过塔机部件类的对象化完成部件几何模型、集合、基准特征创建、单元选取和网格划分,再通过塔机装配类的对象化完成不同结构形式、不同配置塔机结构有限元模型的装配,约束关系的设置,荷载与边界条件的施加和集合的创建,结果表明该方法可快速实现不同结构形式、不同配置塔机结构有限元模型的创建。

塔式起重机片式标准节的焊接变形预测与反变形工装研究

随着建筑技术的进步和建筑规模的扩大,塔式起重机的高度及吊装物品质量不断增加,要求片式标准节必须具有更高的强度和刚度才能保证起重机能安全地承载更重的负载。目前,塔式起重机片式标准节在焊接过程中尚存在较严重的焊接变形问题,严重影响了塔式起重机的装配工艺。为实现塔式起重机片式标准节在焊接过程中的支撑和焊后变形的检测及反变形修复,文中通过有限元分析完成了对片式标准节焊接的变形预测,并设计了一款基于反变形原理的塔式起重机片式标准节焊接工装,其功能包括塔式起重机片式标准节焊接件的夹紧固定、焊接过程所引起片式标准节变形的测量、基于变形数据进行反变形调节等。通过专用工装夹具及选型设计的变形量测量模块与支反力模块配合,从而在焊接过程中完成变形矫正,进而实现塔式起重机片式标准节的精准焊接。这一设计不仅提高了片式标准节的焊接质量,焊接效率也有明显的提高。

虚拟化教学试验平台在 Crane CAI 中的应用尝试

试把虚拟仪器技术应用于ＣＡＩ开发，探讨了研究虚拟化教学试验平台的意义，结合工程起重机教学，研制了塔式起重机动载影响系数动力反应模拟试验演示台，并给出了其建立的方法和过程。

基于STM32的塔机数据采集和监控系统设计

针对塔机作业对运行状态参数和作业环境实时监测的需求,设计了一种基于STM32的塔机数据采集和监控系统。该系统采用STM32F103RCT6为核心的微处理器对塔机运行各项状态参数结合传感器进行数据采集和处理,传感器信号经带数字隔离的A/D转换模块和RS485转TTL模块传输到微处理器,微处理器通过串口转以太网模块将采集的传感器数据发送到由工业交换机和网络摄像机组建的局域网中。最后,采用Java语言结合Spring Boot框架开发系统上位机页面对传感器数据和视频监控画面进行显示。通过测试,该系统能够对塔机运行状态参数和塔机作业环境进行实时监测,传感器采集数据的平均相对误差为0.74%,摄像机监控画面平均延时20.4 ms,实现了数据高速准确的实时监测,满足了监测塔机的系统需求。

Intelligent virtualization of crane lifting using laser scanning technology

Background This paper presents an intelligent path planner for lifting tasks by tower cranes in highly complex environments,such as old industrial plants that were built many decades ago and sites used as tentative storage spaces.Generally,these environments do not have workable digital models and 3 D representations are impractical.Methods The current investigation introduces the use of cutting edge laser scanning technology to convert real environments into virtualized versions of the construction sites or plants in the form of point clouds.The challenge is in dealing with the large point cloud datasets from the multiple scans needed to produce a complete virtualized model.The tower crane is also virtualized for the purpose of path planning.A parallelized genetic algorithm is employed to achieve intelligent path planning for the lifting task performed by tower cranes in complicated environments taking advantage of graphics processing unit technology,which has high computing performance yet low cost.Results Optimal lifting paths are generate d in several seconds.

超高层建筑工程内爬塔式起重机附着提升拆除关键技术

内爬塔式起重机是适用于超高层建筑的一种大型设备,本研究介绍了内爬塔结构系统构造及爬升流程,通过设置支撑梁承受结构重力和塔式起重机设计荷载、设置液压油缸和内爬框架进行顶升操作,完成内爬塔结构提升。以小塔拆大塔为塔式起重机拆除原则,设计了两次屋面吊拆除过程,保障拆除工期和屋面结构安全。建立了支撑梁和内爬框架的三维实体有限元计算模型,优化支撑梁系统设计,得到了支撑梁和内爬框架在满载支撑状态下的应力和位移计算结果。结果表明,支撑系统安全可靠。

塔吊基础、附墙杆和预埋件分类和安装方法

当塔吊超过独立高度后,为保证塔身整体稳定性,需将塔吊依附于建筑物进行锚固约束,因此,附着位置的可靠连接显得尤为重要。论文主要介绍了塔吊基础的分类和安装工艺流程,以及塔吊附着安装工艺流程,总结了3种附墙杆的特点和安装工法,以及附墙埋件的分类和安装工法。

基于节段模型测力方法的塔式起重机风荷载特性研究

塔式起重机被广泛应用于铁道工程和土木工程施工过程,属于高耸结构体系,风荷载是塔式起重机结构设计的控制性荷载。为完善《塔式起重机设计规范》(GB/T 13752—2017)和《建筑结构荷载规范》(GB 50009—2012)中的塔式起重机斜风向设计风荷载计算方法,解决风向、吊臂、平衡臂位置等因素对塔式起重机遮挡和干扰引起的设计风荷载计算问题。选取平头塔式起重机为研究对象,对塔身、吊臂、平衡臂进行多工况的节段模型测力风洞试验,研究湍流强度、节段干扰和遮挡等因素对塔式起重机节段风荷载特性的影响规律,研究不同风向下节段阻力系数分布规律,对比标准化阻力系数与当前主要规范的异同,进而探讨节段斜风向标准化阻力系数计算方法。研究结果表明湍流强度对节段阻力系数影响较小,可忽略,而平衡臂和吊臂相邻节段的干扰会减小测试节段的阻力系数;在斜风向下,由于吊臂和平衡臂之间存在相邻节段干扰,国内外规范方法的计算值均会大于干扰工况的节段风洞试验值;当前主要国家规范规定的垂直风向塔身、吊臂、平衡臂阻力系数与风洞试验测得的阻力系数值较为接近,基于风洞试验结果给出典型风向的塔式起重机各节段的风荷载系数取值可用于结构设计;基于风洞试验测试结果推导的塔式起重机斜风向风荷载计算方法具有较好的拟合效果。研究成果可推荐相关工程应用,可为相关规范的修改或补充提供参考。

塔式起重机相关知识与使用管理

介绍了塔式起重机的相关知识,包括电力驱动特点、供电电缆、配电箱与隔离开关、供电制及漏电保护器、润滑材料及选用原则、稳定性计算等,总结了塔式起重机的操作规程、技术管理要点及安装程序。

塔式起重机附着装置相关要求说明及临时锚固正确方法的探讨

介绍了塔式起重机附墙的基本作用和相关名词的解释,阐述了附着装置的设计标准,通过模型演算塔式起重机临时锚固时吊臂的受力状况,并通过演算结果得出正确的锚固方法,以指导塔式起重机采取正确合适的锚固措施。

装配式混凝土建筑施工现场群塔布置的影响因素分析

装配式混凝土建筑的预制构件类型繁多、数量大,现场吊装作业任务量大。装配式混凝土建筑施工现场进行群塔布置时需要考虑塔吊的选型、施工场地和道路情况、塔吊的站位和群塔作业防碰撞要求等因素。在保证群塔施工中相互运行安全的前提下,群塔的合理布置应可最大限度地提高群塔利用效率,满足施工要求。

风荷载作用下塔式起重机结构的随机振动分析

对塔式起重机的研究一般是将风荷载进行应力等效或者是流体分析,而本文将结合脉动风的随机特性与Ansys的随机振动模块进行分析。首先计算塔机在非工作状况下的预应力模态,确定其固有频率及振型;其次基于Davenport风速谱计算出随机振动模块所需的PSD数据;最后从后处理模块中得到所需的数值。

密度峰值聚类在塔机损伤诊断中的应用研究

建立塔机有限元模型,获取塔机完好状态和各损伤工况的各采集点的动态位移。提出了两种模型建立方法,基于悬臂梁的双输入单输出模型和基于时域数据的动态双输入单输出模型,对基于时域数据的双输入单输出模型首先利用最小二乘法计算参数初值,进一步利用粒子群优化方法进行参数优化,提高了模型精度。以完好工况的塔机数据为基础,建立基于悬臂梁的双输入单输出模型和基于时域数据的双输入单输出模型,计算参数,建立损伤识别模型,用待检状态的位移数值拟合模型,用两种模型计算出的残差方差做损伤因子,利用密度峰值聚类方法对损伤因子进行分析,实现了对塔机的损伤判定和损伤位置的确定。这种基于密度峰值聚类的诊断方法可对塔机微小损伤进行智能诊断和位置确定,该方法只需要塔机完好状态的数据和待检状态的数据即可自动诊断,解决了塔机损伤识别中损伤数据难以获取,因而无法实现智能训练和诊断的问题。