Search

Lifting is to use lifting equipment to lift components and install them to the designated position. On the main structure, lifting equipment is used to transport the flue and transport the sectional flue to the designated position. Certain deformation will occur during the lifting operation of the flue due to its force condition, but it is not known whether it is elastic deformation or plastic deformation. Therefore, this paper analyzes the stress and strain of the flue during operation by finite element method, and observes and analyzes the influence of plastic deformation on the whole flue. [ABSTRACT FROM AUTHOR]

Hoisting is essential for large-scale construction projects, including urban viaducts, high-rise buildings, and undersea tunnels. However, this critical process is subject to frequent safety accidents in China, which result in many casualties and asset losses. The lack of a practical risk framework has contributed to poor safety management in this field. Most of the limited risk frameworks in this field focus only on the direct causes leading to accidents, ignoring the systematic and complex nature of lifting risks. In this study, a new risk framework for lifting is constructed by combining the STAMP (Systems-Theoretic Accident Model and Processes) theory and the quantitative analysis capability of the PLS-SEM (Partial Least Squares Structural Equation Modeling) to effectively identify, assess, and manage various potential risks in the lifting construction process. The factors were then analyzed for importance through the independence weight coefficient method. The study found that “Failure to conduct pre-operational inspections of lifting equipment and rigging components,” “Physical or mental impairment of operators, such as intoxication or distraction,” and “The hoisting program was not prepared under the actual working conditions at the project site and did not adequately plan for emergencies,” were the factors with the top 3 highest weight. Ultimately, the framework is validated by 200 real cases from 2019 to 2024 in China. This proposed STAMP-HC framework can accurately identify the risk transfer paths in accidents, and the results of risk factor weighting can also provide a reference for risk management, with the potential to be extended to other countries.

Lifting is to use lifting equipment to lift components and install them to the designated position. On the main structure, lifting equipment is used to transport the flue and transport the sectional flue to the designated position. Certain deformation will occur during the lifting operation of the flue due to its force condition, but it is not known whether it is elastic deformation or plastic deformation. Therefore, this paper analyzes the stress and strain of the flue during operation by finite element method, and observes and analyzes the influence of plastic deformation on the whole flue.

Hoisting is an essential aspect of Industrial Building System (IBS) construction. Although research on hoisting safety in China has made strides to focus on “worker,” “data,” “task,” “site,” and “accident,” there still needs to be more approaches based on multi-dimensional social system thinking. Therefore, the paper aims to fill this gap. We investigated 105 hoisting accidents in China and found that hoisting accidents occurred most frequently in China's southeast coastal region; truck-mounted cranes and tower cranes were the most common types of machinery involved in accidents; hoisting load off, capsizing of crane machinery, and workers falling from height are the three most common accident types; the average impact of a single hoisting accident is approximately RMB 2.43 million direct economic loss, 1.543 deaths and 0.829 injured. This study used three algorithms (Rindge regression, Lasson regression, and partial least squares regression) to explore the impact of deaths and injuries on direct economic losses. By combining Rasmussen's risk framework with the characteristics of hoisting construction, six risk domains and thirty-six safety risk factors were identified. Finally, we used AcciMap technology to construct a qualitative IBS hoisting management model, which exhaustively presents the systematic levels and propagation paths of the influencing factors by the PDCA method. The research helps academics explore strategies to improve the safety of hoisting construction in IBS. Moreover, the study outcomes can inform the policy-making process towards promoting healthy and sustainable construction development.

To adapt to the trend of prefabricated development in waterway transportation engineering, and promote the industrialization development of waterway transportation engineering in the design, industrialization manufacture, and assemble construction of prefabricated caissons, the process of block prefabrication, reinforcement connection, component lifting, wall panel joint treatment method, and structural impermeability of the prefabricated caissons were investigated through the design and experimental construction of the prefabricated caissons. The results show that the prefabricated scheme is feasible in general, and the application of this technology in the field of water transportation engineering is also prospected. [ABSTRACT FROM AUTHOR]

Taking a new pile turning technology for offshore hoisting of extra large diameter steel pipe piles for analysis, the core lifting appliances, characteristics of the main technology and pile turning performance of the new pile turning technology is presented. After analyzing and calculating the safe stress of the lifting appliances for pile turning were made, the new pile turning technology was used for hoisting and turning of extra large diameter, super long and overweight single steel pipe piles for Huaneng Cangnan No.2 Offshore Wind Power Project. It was verified through the practice that the new pile turning technology with pelican hooks ensured stable pile turning control and safe lifting of a steel pipe pile, and also used less time for pile turning and hoisting as well as had high work efficiency. At the same time, with this technology, a pile could be lifted and turned with only a single vessel without the assistance of auxiliary lifting vessels, thus cutting down the project costs and gaining high economic benefits. The new pile turning technology can be widely used in turning and hoisting of extra large diameter, super long and overweight steel pipe piles in port engineering and offshore wind power projects. [ABSTRACT FROM AUTHOR]

Copyright of Railway Construction Technology is the property of Railway Construction Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Construction faces many safety accidents with urbanization, particularly in hoisting. However, there is a lack of systematic review studies in this area. This paper explored the factors and methods of risk assessment in hoisting for industrial building system (IBS) construction. Firstly, bibliometric analysis revealed that future research will focus on "ergonomics", "machine learning", "computer simulation", and "wearable sensors". Secondly, the previous 80 factors contributing to hoisting risks were summarized from a "human–equipment–management–material–environment" perspective, which can serve as a reference point for managers. Finally, we discussed, in-depth, the application of artificial neural networks (ANNs) and digital twins (DT). ANNs have improved the efficiency and accuracy of risk assessment. Still, they require high-quality and significant data, which traditional methods do not provide, resulting in the low accuracy of risk simulation results. DT data are emerging as an alternative, enabling stakeholders to visualize and analyze the construction process. However, DT's interactivity, high cost, and information security need further improvement. Based on the discussion and analysis, the risk control model created in this paper guides the direction for future research. [ABSTRACT FROM AUTHOR]

Copyright of Railway Construction Technology is the property of Railway Construction Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents a smooth command (SC) input shaper for suppressing payload oscillations in rest-to-rest simultaneous radial and tangential motions of a tower crane. The radial and tangential acceleration profiles of the compound motions are represented by multi-sine wave functions with independent and variable maneuvering time. The proposed SC is designed using a nonlinear mathematical model of the tower crane while the parameters of the acceleration profiles and maneuvering times were optimized using a particle swarm algorithm (PSO). The simulated results were verified experimentally on a laboratory scale tower crane. The results confirm that the proposed SC input effectively canceled residual vibrations of the payload compound motions with a time length comparable to zero vibrations (ZV) shaper. Moreover, sensitivity analysis to variations in cable length reveals that the proposed command input is robust over a wide range of cable lengths. [ABSTRACT FROM AUTHOR]

Minimizing failing test cases is an important preprocessing step on the path of debugging. If much of a test case that triggered a bug does not contribute to the actual failure, then the time required to fix the bug can increase considerably. However, test case reduction itself can be a time‐consuming task, especially if done manually. Therefore, automated minimization techniques have been proposed, the minimizing Delta Debugging and the Hierarchical Delta Debugging (HDD) algorithms being the most well known. In this paper, we investigated the input format of HDD, searching for structures that the algorithm cannot reduce. Motivated by the findings, we have created an algorithmic framework that enabled the use of transformations other than pruning. Furthermore, with the Transformation‐based Minimization framework, we propose to extend HDD and its coarse and recursive variants with a reduction method that does not prune subtrees but replaces them with compatible subtrees further down the hierarchy, called hoisting. We have evaluated various combinations of pruning and hoisting on multiple test suites and found that hoisting can help to further reduce the size of test cases by 27% on average and by 80% as best case compared with the baseline algorithm. [ABSTRACT FROM AUTHOR]

Construction faces many safety accidents with urbanization, particularly in hoisting. However, there is a lack of systematic review studies in this area. This paper explored the factors and methods of risk assessment in hoisting for industrial building system (IBS) construction. Firstly, bibliometric analysis revealed that future research will focus on “ergonomics”, “machine learning”, “computer simulation”, and “wearable sensors”. Secondly, the previous 80 factors contributing to hoisting risks were summarized from a “human–equipment–management–material–environment” perspective, which can serve as a reference point for managers. Finally, we discussed, in-depth, the application of artificial neural networks (ANNs) and digital twins (DT). ANNs have improved the efficiency and accuracy of risk assessment. Still, they require high-quality and significant data, which traditional methods do not provide, resulting in the low accuracy of risk simulation results. DT data are emerging as an alternative, enabling stakeholders to visualize and analyze the construction process. However, DT’s interactivity, high cost, and information security need further improvement. Based on the discussion and analysis, the risk control model created in this paper guides the direction for future research.

In the hoisting equipment, the hoisting or lowering of the load at the hook is done with the drilling cable that connects the sheaves from the crown-block and those from the travelling-block. Failure of the drilling line can have catastrophic effects, hence it is very important to evaluate as accurately as possible the values of the lines tensions, so that during the drilling operations they do not exceed their tensile limits. The present paper deals with the study regarding the dynamics of the of the travelling block- crown block mechanism with two active drawworks and is establishing the expressions for calculation of the tensions from the drilling lines, depending on the load applied at the hook during both hoisting and lowering operations. The calculation is performed for the case of the travelling block-crown block mechanism provided with 3 respectively 4 sheaves and the values of the lines tensions for a hoisting equipment with two active drawworks are compared with the values for the conventional hoisting equipment.

Virtual reality (VR) simulation training for helicopter search and rescues (SAR) hoist operators is very uncommon in comparison to the availability of pilot simulation training. SAR hoist operators control winch systems for hoisting objects or people during helicopter flight. Using a rear crew helicopter VR training simulator we sought to quantify hoist operator performance and validate this system by showing that experienced SAR hoist operators and novices hoist differently. We recruited 12 military SARs and 11 persons without hoisting experience and examined their performance in moderate wind conditions over two landscapes, ocean and land. Experienced operators were not affected by environment, completed missions faster than novices, made fewer velocity adjustments, and demonstrated better cable management. These variables can now be used as sources of feedback to train novice hoist operators. Since there were differences between performances of experienced and novice hoist operators we have established construct validity of the simulator. [ABSTRACT FROM AUTHOR]

The hoisting of prefabricated components (PCs) is a key step during the construction of prefabricated buildings. Aiming at the problems existing in the control of PC hoisting, an innovative hoisting management system framework based on the digital twin (DT) is established in this paper. The system framework comprehensively utilizes the building information model (BIM) and Internet of Things (IoT) to establish a digital twin model (DTm) for PC hoisting control and uses Dijkstra's algorithm to conduct hoisting route planning according to the BIM data in the model. Meanwhile, long-range radio (LoRa) technology was used for data acquisition and transmission to monitor the movement state of the PCs in the hoisting process. By testing it in a prefabricated building project, the DT control method was conducted to realize the functions of real-time information collection, hoisting path planning and PC positioning, which proved the feasibility and effectiveness of the method. As a key technology to realize intelligent manufacturing, DT has been widely studied in academia. The DTm of the hoisting process of PCs is established in this study; it improves the level of intelligent management of prefabricated building construction and provides a new idea for intelligent building construction. [ABSTRACT FROM AUTHOR]

Wrapping objects using ropes is a common practice in our daily life. However, it is difficult to design and tie ropes on a 3D object with complex topology and geometry features while ensuring wrapping security and easy operation. In this article, we propose to compute a rope net that can tightly wrap around various 3D shapes. Our computed rope net not only immobilizes the object but also maintains the load balance during lifting. Based on the key observation that if every knot of the net has four adjacent curve edges, then only a single rope is needed to construct the entire net. We reformulate the rope net computation problem into a constrained curve network optimization. We propose a discrete-continuous optimization approach, where the topological constraints are satisfied in the discrete phase and the geometrical goals are achieved in the continuous stage. We also develop a hoist planning to pick anchor points so that the rope net equally distributes the load during hoisting. Furthermore, we simulate the wrapping process and use it to guide the physical rope net construction process. We demonstrate the effectiveness of our method on 3D objects with varying geometric and topological complexity. In addition, we conduct physical experiments to demonstrate the practicability of our method. [ABSTRACT FROM AUTHOR]

Lattice boom mobile cranes are mainly used to move heavy payloads with a large hoisting radius. During this work, crane motions cause dynamic forces on the crane's structure. In order to guarantee the safety of cranes, exact calculations are absolutely essential for the boom system. The calculation standards stipulate the use of special dynamic factors to estimate the dynamic loads. Several research projects have shown, that the standards often describe the dynamic effects only approximately. In order to calculate the dynamic behaviour accurately, without a disproportionate increase in computing time, special vibration models have been developed in a current research project. This paper presents a new vibration model for the process of hoisting suspended loads. The model is based on the response spectrum method and describes the dynamic effects in an exact way.

Copyright of Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A connecting structure between the ignitor and the BOP stack is proposed, and a three-dimensional model and a finite element model are established. Taking the 11" pilot tube with the corresponding ram BOP as an example, the impact force and wind load effect on the field operation are analyzed by ANSYS finite element simulation, and the mechanical properties of the weak points when the 13-3/8" pilot tube is suspended at high temperature (800 °C). The simulation results show that: the maximum equivalent stress of 11" BOP structure is about 65 MPa under the condition of only bearing its own gravity, and 64 MPa under the impact force of wellhead, all of which are located at the branch of ignition tube; under the condition of level 6 wind load, the influence is very small and can be ignored; the maximum stress of 13-3/8" BOP structure at high temperature appears at the opening on both sides, which is 58. 4 MPa, with deformation 27 mm more than that at room temperature, which has little effect on the overall structure. The connection structure between the pilot tube and the BOP group can meet the field operation conditions, which has guiding significance for the next step of well control rescue operation and tool design. [ABSTRACT FROM AUTHOR]

The hoisting of prefabricated components (PCs) is a key step during the construction of prefabricated buildings. Aiming at the problems existing in the control of PC hoisting, an innovative hoisting management system framework based on the digital twin (DT) is established in this paper. The system framework comprehensively utilizes the building information model (BIM) and Internet of Things (IoT) to establish a digital twin model (DTm) for PC hoisting control and uses Dijkstra’s algorithm to conduct hoisting route planning according to the BIM data in the model. Meanwhile, long-range radio (LoRa) technology was used for data acquisition and transmission to monitor the movement state of the PCs in the hoisting process. By testing it in a prefabricated building project, the DT control method was conducted to realize the functions of real-time information collection, hoisting path planning and PC positioning, which proved the feasibility and effectiveness of the method. As a key technology to realize intelligent manufacturing, DT has been widely studied in academia. The DTm of the hoisting process of PCs is established in this study; it improves the level of intelligent management of prefabricated building construction and provides a new idea for intelligent building construction.

Some authors have downplayed the importance of complex vaulted systems in ashlar in Roman architecture. This has led them to seek the origins of Early Modern stonecutting in Christian Syria or Languedocian Romanesque. However, some examples in many regions of the Empire, including Lazio, argue for the existence of advanced stonecutting techniques in the Roman world. In this paper, we will study an interesting example of these structures, the Grotta dei Massacci in Osteria Nuova, now in the municipality of Frasso Sabino. Starting with a precise survey carried out by 3D laser scanning and automated photogrammetry, we will put forward some hypotheses about its measurement system, proportion, stonecutting technique and the hoisting systems used in its execution. [ABSTRACT FROM AUTHOR]

Background: In anesthetized adult horses, changes in recumbency can influence the cardiovascular system but how arterial blood pressures and oxygen tension change in isoflurane anesthetized animals as a direct result of hoisting has not been investigated.Objective: To evaluate effects of hoisting on hemodynamic function and pulmonary gas exchange in isoflurane-anesthetized horses.Study Design: Prospective, experimental study.Methods: Six adult horses were anesthetized three times using isoflurane in pure oxygen (inspired fraction 0.9–1.0), and allowed breathing spontaneously in lateral recumbency. After 45 min horses were hoisted using a single hoist-hobble system for 5 min and returned into left lateral recumbency. Heart rate (HR), respiratory rate (RR), and systolic (SAP), diastolic (DAP), and mean arterial blood pressures (MAP) were measured every minute starting from 5 min before to 5 min after hoisting. Arterial blood gas samples were collected before, during, and after hoisting.Results: Significant changes in hemodynamic parameters and PaO2 but not PaCO2 were found between baseline recordings and measurements obtained during and early after hoisting. The MAP decreased within the 1st min of hoisting from a mean of 74 ± 17 mmHg at baseline to 57 ± 20 mmHg (p < 0.05). Thereafter, it rapidly recovered to baseline before continuing to rise to higher than baseline values and then remaining elevated for 5 min after horses were returned into lateral recumbency. Simultaneously, the HR increased by 6–9 beats per min during the initial 3 min of hoisting before returning close to baseline values (p < 0.05). The PaO2 decreased significantly from a mean of 324.9 ±137.0 mmHg at baseline to a mean of 141.3 ± 104.2 mmHg during hoisting (p < 0.001) without recovering any more to baseline values.Clinical significance: Hoisting an adult horse during or at the end of isoflurane anesthesia carries the risk of a precipitous, though short-lived (1–2 min), drop in arterial blood pressures and a persistent decrease in arterial oxygenation. While in systemically healthy animals the observed functional impairments were not life-threatening, they may be more severe in systemically compromised horses.Therefore, arterial blood pressures and oxygenation must be carefully monitored when hoisting sick equine patients during or at the end of inhalant anesthesia.

Copyright of Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the process of using a long-span converter station steel structure, engineering disasters can easily occur. Structural monitoring is an important method to reduce hoisting risk. In previous engineering cases, the structural monitoring of long-span converter station steel structure hoisting is rare. Thus, no relevant hoisting experience can be referenced. Traditional monitoring methods have a small scope of application, making it difficult to coordinate monitoring and construction control. In the monitoring process, many problems arise, such as complicated installation processes, large-scale data processing, and large-scale installation errors. With a real-time structural monitoring system, the mechanical changes in the long-span converter station steel structure during the hoisting process can be monitored in real-time in order to achieve real-time warning of engineering disasters, timely identification of engineering issues, and allow for rapid decision-making, thus avoiding the occurrence of engineering disasters. Based on this concept, automatic monitoring and manual measurement of the mechanical changes in the longest long-span converter station steel structure in the world is carried out, and the monitoring results were compared with the corresponding numerical simulation results in order to develop a real-time structural monitoring system for the whole long-span converter station steel structure’s multi-point lifting process. This approach collects the monitoring data and outputs the deflection, stress, strain, wind force, and temperature of the long-span converter station steel structure in real-time, enabling real-time monitoring to ensure the safety of the lifting process. This research offers a new method and basis for the structural monitoring of the multi-point hoisting of a long-span converter station steel structure.

Hoisting is an essential aspect of Industrial Building System (IBS) construction. Although research on hoisting safety in China has made strides to focus on "worker," "data," "task," "site," and "accident," there still needs to be more approaches based on multi-dimensional social system thinking. Therefore, the paper aims to fill this gap. We investigated 105 hoisting accidents in China and found that hoisting accidents occurred most frequently in China's southeast coastal region; truck-mounted cranes and tower cranes were the most common types of machinery involved in accidents; hoisting load off, capsizing of crane machinery, and workers falling from height are the three most common accident types; the average impact of a single hoisting accident is approximately RMB 2.43 million direct economic loss, 1.543 deaths and 0.829 injured. This study used three algorithms (Rindge regression, Lasson regression, and partial least squares regression) to explore the impact of deaths and injuries on direct economic losses. By combining Rasmussen's risk framework with the characteristics of hoisting construction, six risk domains and thirty-six safety risk factors were identified. Finally, we used AcciMap technology to construct a qualitative IBS hoisting management model, which exhaustively presents the systematic levels and propagation paths of the influencing factors by the PDCA method. The research helps academics explore strategies to improve the safety of hoisting construction in IBS. Moreover, the study outcomes can inform the policy-making process towards promoting healthy and sustainable construction development., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

Copyright of Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Scientific Bulletin of National Mining University is the property of National Mining University, State Higher Educational Institution and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Highlights • We propose an improved unity magnitude input shaping (UMZV) for control of a 3D overhead crane. • The technique can adapt to the changes in the cable length for efficient sway control. • The shaper achieves significant reductions in maximum transient and residual sways. • Experiments verify the superiority of the improved UMZV shaper. Abstract This paper proposes an improved unity magnitude zero vibration (UMZV) shaper for payload sway reduction of an underactuated 3D overhead crane with hoisting effects. The proposed technique is effective in adapting to changes in the cable length and the crane dynamics during hoisting and thus provides higher sway reductions. The shaper is designed using the relationship of optimal UMZV shaper parameters and cable length obtained using a nonlinear model of a 3D overhead crane and particle swarm optimisation. A technique to choose the shaper parameters automatically during the hoisting operation is designed. To test the effectiveness of the proposed technique, MATLAB simulation and experiments are carried out on a laboratory crane under two hoisting cases. The superiority of the proposed technique is confirmed by achieving at least two-fold reductions in maximum transient and residual sways of the laboratory crane when compared to the Average Travel Length technique. The advantage of the improved UMZV shaper is also demonstrated with the simulation results. It is envisaged that the method can be useful for an operator to handle cranes in three dimensions without motion-induced sway problem. [ABSTRACT FROM AUTHOR]

Prefabricated buildings are widely used because of their green environmental protection and high degree of industrialization. However, in construction process, there are some defects such as small wireless network coverage, high-energy consumption, inaccurate control, and backward blind hoisting methods in the hoisting process of prefabricated components (PC). Internet-of-Things (IoT) technology can be used to collect and transmit data to strengthen the management of construction sites. The purpose of this study was to establish an intelligent control method in the construction and hoisting process of PC by using IoT technology. Long Range Radio (LoRa) technology was used to conduct data terminal acquisition and wireless transmission in the construction site. The Inertial Measurement Unit (IMU), Global Positioning System (GPS), and other multi-sensor fusion was used to collect information during the hoisting process of PC, and multi-sensor information was fused by fusion location algorithm for location control. Finally, the feasibility of this method was verified by a project as a case. The results showed that the IoT technology can strengthen the management ability of PC in the hoisting process, and improve the visualization level of the hoisting process of PC. Analysis of the existing outdated PC hoisting management methods, LoRa, IMU, GPS and other sensors were used for data acquisition and transmission, the PC hoisting multi-level management and intelligent control.

Crane ship has a strict requirement on open sea state during its operation. Operation window requirement was mainly decided by mariner experience or numerical simulation on ship system. Taking a 1 600 t crane ship as the research object, we adopted a physical model test approach to test and analyze the dynamic response of crane ship in hoisting and nonhoisting state. The results show that the movement of crane ship under hoisting condition is less than that under non-hoisting condition. After analysis on movement of crane ship in non-hoisting state under wind wave or long period swell, wave condition requirement during construction period is achieved. These research results provide the technical reference and support for the offshore operation of the crane ship, especially under the long period wave condition. [ABSTRACT FROM AUTHOR]

Abstract: Cables are used in many engineering applications, whether considered as stationary or running cables. In the latter, ropes are subjected to repeated tension and bending as they run over a sheave wheel. Such loading scenarios are seen for large mining equipment such as draglines and shovel hoist ropes. Fretting fatigue failure often occurs after several cycles of loading because of wires rubbing against each other and external wires rubbing against sheave wheels. It is also pertinent to understand the behaviour of cables subjected to bending over sheaves, to be able to predict fretting fatigue life, so as to set preventive maintenance activities to avoid catastrophic failure in such systems. In this paper, the behaviour of 2 specific configuration strands, composing either 7 or 19 wires, bent over a sheave is investigated numerically. To aid preventive maintenance inspection, critical locations of stress concentrations are identified as a function of applied load or tensile stress. The investigation also considers the impact of groove size, diameter of sheave to diameter of cable ratio, and contact length, enabling the application to infer fatigue life. [ABSTRACT FROM AUTHOR]

This paper proposes an improved input shaping for minimising payload swing of an overhead crane with payload hoisting and payload mass variations. A real time unity magnitude zero vibration (UMZV) shaper is designed by using an artificial neural network trained by particle swarm optimisation. The proposed technique could predict and directly update the shaper’s parameters in real time to handle the effects of time-varying parameters during the crane operation with hoisting. To evaluate the performances of the proposed method, experiments are conducted on a laboratory overhead crane with a payload hoisting, different payload masses and two different crane motions. The superiority of the proposed method is confirmed by reductions of at least 38.9% and 91.3% in the overall and residual swing responses, respectively over a UMZV shaper designed using an average operating frequency and a robust shaper namely Zero Vibration Derivative-Derivative (ZVDD). The proposed method also demonstrates a significant residual swing suppression as compared to a ZVDD shaper designed based on varying frequency. In addition, the significant reductions are achieved with a less shaper duration resulting in a satisfactory speed of response. It is envisaged that the proposed method can be used for designing effective input shapers for payload swing suppression of a crane with time-varying parameters and for a crane that employ finite actuation states. [ABSTRACT FROM AUTHOR]

Cables are used in civil and mining engineering applications, such as in cable stays for suspension bridges, elevators, construction cranes, mining shovels and draglines. Such cables are mainly used for supporting or hoisting and can be considered to be either stationary or running cables. In supporting functions, cables are subjected to cyclic tension, with the primary mode of failure due to fretting fatigue of individual wires that make up the cables as they abrade against each other. Stationary cables subjected to cyclic tension (tension–tension) fatigue are the focus of this work, and although other researchers have investigated the fatigue life of such cables, there remains much of the cyclic tensile behavior that needs further investigation. The stress condition of several cables such as 19-, 91- and 92-wire strands; independent wire rope core; and the 6 × 19 Seale–independent wire rope core wire ropes was investigated using finite element modeling techniques. A stress-based approach was used with the results of finite element modeling to obtain the fatigue life for these cables. In practice, it would be challenging for a finite element analysis to be carried out each time the fatigue life of a cable is needed, so in a preventive maintenance stance, regression coefficients have been proposed for use with a fatigue life prediction model. [ABSTRACT FROM AUTHOR]

The closure joint of HZMB island and tunnel project weighs over 6 000 t, and its hoisting process is carried out by a 12 000 t crane ship, which is the largest hoisting operation in China. A critical problem for its installation is to understand the axial movement of the closure joint along the tunnel when the closure joint structure is lowered down into the slot, and then to judge the likelihood of collision between the closure joint and the adjacent tunnel elements. Based on the cognition of marine condition and construction method, we deduced analytical results of the maximum displacement of the closure joint during installation into the slot, by means of the combined use of equation of simple pendulum and ship dynamics. The results is in good agreement with the observations of the actual operation works. [ABSTRACT FROM AUTHOR]

A new solution is presented to the problem of controlling the motion of a crane’s suspended load through arbitrarily complex, 3D paths through the crane’s manoeuvre space. A generalized boom crane arrangement is considered, so that gantry and luffing arrangements are included as particular cases. Thus the crane’s boom slews about a central, vertical (tower) axis. This boom is either a horizontal gantry with a trolley moving radially along it, from which the load can be winched, or a jib, which can rotate in the vertical plane, with the hoisting cable passing over a pulley attached at its end point. In either case, there are three directly controlled motion variables, the effects of which on the suspended payload’s motion are strongly cross-coupled. The challenge is to enable the payload to follow the desired 3D path as closely as possible during the manoeuvre, and come to rest rapidly at target, by directly controlling these three actuating motions. Thus the controller must achieve position control combined with active swing suppression throughout the manoeuvre and on arrival at the desired end point. A model is developed of the generalized crane for both gantry and luffing crane types. The proposed control strategy is then applied and tested on this model. The controller is based on mechanical wave concepts. When applied to the model, it is shown to be very effective. It is accurate, robust to system changes and actuator limitations, very stable, requires sensing only at the trolley (and not at payload), and is easy to implement. [ABSTRACT FROM AUTHOR]

This paper presents an output-based command shaping (OCS) technique for an effective payload sway control of a 3D crane with hoisting. A crane is a challenging and time-varying system, as the cable length changes during the operation. The OCS technique is designed based on output signals of an actual system and reference model, does not require the natural frequency and damping ratio of the system, and thus can be utilized to minimize the hoisting effects on the payload sway. The shaper was designed by using the derived non-linear model of a 3D crane. To test the effectiveness of the controller, simulations using a non-linear 3D crane model and experiments on a lab-scale 3D crane were performed and compared with a zero vibration derivative (ZVD) shaper and a ZVD shaper designed using an average travel length (ATL) technique. In both the simulations and the experiments, the OCS technique was shown to be superior in reducing the payload sway with reductions of more than 56% and 33% in both of the transient and residual sways that were achieved when compared with both the ZVD and the ATL shapers, respectively. In addition, the OCS technique provided the fastest time response during the hoisting. It is envisaged that the method can be very useful in reducing the complexity of closed-loop controllers for both tracking and sway control. [ABSTRACT FROM AUTHOR]

Classical input shaping is based on convolving a general input signal with a sequence of timed impulses. These impulses are chosen to match certain modal parameters of the system under control to eliminate residual vibrations in rest-to-rest maneuvers. This type of input shaping is strongly dependent on the system period. In this work, an adjustable maneuvering time wave form command shaper is presented. The equation of motion of a simple pendulum model of a crane is derived and solved in order to eliminate residual vibrations at the end of motion. Several cases are simulated numerically and validated experimentally on an experimental model of an overhead crane. Results show that the proposed command shaper is capable of eliminating residual vibrations effectively with a single continuous wave form command. The work is extended to include the effect of hoisting on the shaper performance. Several functions are used to simulate hoisting. To overcome the added complexity of hoisting on the system, an approximation technique is used to determine initial shaped command parameters, which are later used in a genetic algorithm optimization scheme. Numerical and experimental results prove that the proposed command shaper can effectively eliminate residual vibrations in rest-to-rest maneuvers. [ABSTRACT FROM AUTHOR]

Contract SBT2.1 'Tunnel Fröschnitzgraben' has a value of about EUR 623 million, the largest contract for the Semmering Base Tunnel. The construction contract was awarded in autumn 2013 to the joint venture Tunnel Fröschnitzgraben Implenia - Swietelsky Tunnelbau. The contract includes altogether about 26 km of running tunnels to be driven by two mechanised drives and two conventional drives, with the works being undertaken at all four faces almost simultaneously. The particular challenge is that the entire supply to the underground activities and the clearance of excavated material has to pass through two shafts about 400 m deep. The construction of these two shafts with excavated diameters of about 12.4 and 9.9 m respectively and the selection of the shaft logistics are of decisive significance for the success of the project. These special requirements of the project faced a limited availability of flexible complete contractors for the construction and operation of shafts. Considering this situation, the joint venture partner Swietelsky Tunnelbau decided to solve the problem in-house and follow new routes with innovative concepts. Das Baulos SBT2.1 'Tunnel Fröschnitzgraben' ist mit einem Auftragswert von etwa 623 Mio. EUR das größte Baulos des Semmering-Basistunnels. Im Herbst 2013 erhielt die Arbeitsgemeinschaft Tunnel Fröschnitzgraben Implenia - Swietelsky Tunnelbau den Bauauftrag. Für die im Baulos insgesamt aufzufahrenden ca. 26 km Streckenröhren sind zwei maschinelle Vortriebe (TVM) und zwei konventionelle Vortriebe vorgesehen. Die Arbeiten werden an allen vier Vortriebsästen großteils zeitgleich abgewickelt. Die besondere Herausforderung liegt darin, dass die gesamte Versorgung der untertägigen Aktivitäten sowie der Abtransport des Ausbruchmaterials über zwei jeweils ca. 400 m tiefe Schächte erfolgen müssen. Die Herstellung der beiden Schächte mit einem Ausbruchdurchmesser von rd. 12,4 bzw. 9,9 m und die Auswahl der Schachtlogistik sind für das Gelingen des Projekts von entscheidender Bedeutung. Den speziellen Anforderungen des Projekts stand ein begrenztes Angebot an flexiblen Komplettanbietern für den Bau und den Betrieb von Schächten gegenüber. Angesichts dieser Situation hat sich der Arge-Partner Swietelsky Tunnelbau dazu entschieden, die Problemstellungen in Eigenregie zu lösen und mit innovativen Konzepten neue Wege zu beschreiten. [ABSTRACT FROM AUTHOR]