On-site Installation Research Articles

On the anchoring of timber walls to foundations: available strategies to prevent wood deterioration and on-site installation problems

Experts are aware that the critical and until now unsolved problem of timber wall buildings lies in proper anchoring of the structure to foundations. Geometric inaccuracies and discrepancies between the concrete surface and the timber structure often lead to incorrect alignment of walls, which is normally solved with provisional and inaccurate solutions, in contrast with prefabrication. However, the most important issue is the compromised durability of timber due to rising dampness and fungicide attack, which are a result of inaccurate waterproofing as moisture is absorbed and trapped at the wall base. Difficulties in restoring such damages arise together with maintenance costs of the structures. This work provides an overview on the crucial problems that affect the anchoring of timber structures to foundations. Disadvantages of traditional techniques are presented and critically discussed. An innovative aluminium bottom rail designed for Cross-Laminated Timber, light-frame and Blockhaus technologies is presented, evidencing main structural properties and capacities in assuring timber durability and long-lasting fixing. This aluminium beam is made of an extruded profile with shape and size optimized for load-bearing capacity and lateral stability. Special grooves at both sides are designed to obtain fast and efficient fixing of shear-resisting plates and hold-downs. Main results from latest experimental campaign are given to characterize the system in terms of load-bearing capacity and case-study applications in newly-realized timber buildings are presented. Finally, a proposal for possible restoring intervention to replace the damaged timber at the base of the wall is hypothesized.

The Transmission Line for the SPIDER Experiment: From design to installation

SPIDER (Source for the Production of Ions of Deuterium Extracted from RF plasma) is the full scale prototype of the Ion Source for the ITER 1MeV Heating Neutral Beam Injector (HNB) and is presently under construction in the Neutral Beam Test Facility at Consorzio RFX premises, in Padua, Italy. The required Ion Source and Extraction Power Supply (ISEPS) system and the associated diagnostics need to be hosted inside a −100kVdc air-insulated Faraday cage, called High Voltage Deck (HVD); a High Voltage Transmission Line (TL) carries many power and signal conductors from the ISEPS to the Ion Source.An air insulated design of the TL, coping with the large dimensions required to host ISEPS diagnostic and power cables and duly screened against Electromagnetic Interferences (EMI), has been conceived. The paper reports on the construction solutions developed by the Manufacturer to meet the design indications and requirements of the technical specification for such unconventional device. Moreover, the factory type tests to validate the design and release the manufacturing of the overall TL are described. Finally, the paper reports on the on-site installation and commissioning activities for the final acceptance concluded in June 2016.

Experimental Analysis of a Heat Cost Allocation Method for Apartment Buildings

The correct estimate of individual thermal energy consumptions, and consequently, a fair heat cost allocation among the residents of apartment buildings with centralized heating systems, represents an important driving force towards energy saving, energy efficiency and the reduction of pollutant emissions. Nowadays, in those contexts where direct heat meters cannot be used because of the layout of the hot water distribution system, electronic Heat Cost Allocators (HCAs) have the highest market share for the assessment of individual thermal energy consumptions. The uncertainty associated with the parameterization of heat cost allocation devices and the installation effects arising in real applications can negatively affect the accuracy of these devices, as far as the estimation of the individual fractions of thermal energy consumption is concerned. This work deals with the experimental analysis of a novel heat cost allocation method for apartment buildings and its comparison with conventional HCAs. The method allows the indirect estimation of the thermal energy exchanged by water radiators without the need for surface temperature measurements, reducing some of the drawbacks associated with the on-site installation. The experimental analysis was carried out in a full-scale central heating system test facility available at the Italian National Metrology Institute (INRIM) and characterized by SI-traceable direct heat meters installed on each water radiator.

Development of A Maintenance Device for Bus-bar PT Voltage Air Switch

When PT breaks down, it takes long time of switching operation before maintenance, which seriously delays the restoration time. Based on the principle of multiple circuit, a live replacement maintenance device for PT voltage air switch is proposed. The following aspects are involved in the design of the device: the principle of device, component selection, device’s assembly and operation process. Through functional test in simulation substation and on-site installation, it is proved that the failed air switch can be lively replaced by the device without switching operation, which greatly reduces the risk on power grid caused by such faulted air switch.

Simulation Based Validation of Supply Chain Effects through ICT enabled Real-time-capability in ETO Production Planning

According to Industry 4.0, real-time information in production planning and control, shows a high potential for optimizing the whole supply chain. The paper considers the plant building industry, especially the off-site fabrication and on-site installation. Traditionally, production planning is centralized following a Master Schedule that rarely is up to date, ignoring deviations on-site. As a result, components are delivered in advance or too late, which create non-value adding activities and high inventory levels. The paper proposes an ICT-supported nearly real-time capable production planning approach, which by means of a simulation, shows a drastically reduction of the inventory level on-site.

모듈러주택 조립을 위한 조립공구의 성능분석

다양한 접합부간의 조립으로 구조를 이루게 되는 모듈러공법에서 현장설치단계의 모듈조립은 구조물의 구조적인 안정성 및 품질에 직접적인 영향을 미칠 수 있는 매우 중요한 공정이다. 그러나 일반적으로 사용되는 수공구 또는 전동공구는 장시간 사용 시 생산성과 조립품질이 저하되는 문제점을 가지고 있다. 이에 에어공구의 장점을 활용한 모듈러주택 전용 조립공구가 개발되었으나, 공구별 성능을 비교하여 성능을 비교 및 평가하는 실험적인 분석은 미흡하였다. 이에 본 연구는 모듈러주택 조립에 사용되는 기존 조립용 공구와 모듈조립용 에어공구를 현장에 적용하여 구조물의 조립품질과 생산성을 공구별로 측정하여 비교 분석 하였다. 그 결과, 기존 조립용 공구와 비교하여 모듈조립용 에어공구가 생산성 및 품질 측면에서 더 우수한 것으로 분석되었다. Modular house is built by assembling various joints. Module assembly in the stage of on-site installation is very important process, because assembly process directly affects the structural stability and the quality. However, manual tools and electric-powered tools have a problem in that assembly productivity and quality are reduced during long-time usage. Although pneumatic assembly tools for modular house have been developed, but empirical analysis to compare and evaluate the performance of tools has not been sufficient. This study compares and analyzes the assembly quality and productivity by applying existing assembly tools and new pneumatic tools to the field. The analysis results show that pneumatic assembly tools are more excellent in terms of assembly productivity and quality.

Modularization for ground engineering construction in the Anyue Gasfield, Sichuan Basin, with the designed annual gas processing capacity of six billion m3

In the Anyue Gasfield, Sichuan Basin, the Lower Cambrian Longwangmiao Fm gas reservoir in Moxi Block has enormous natural gas reserves, and it is a typical three-high (high temperature, high pressure, and high flow rate) sour gas field. Its ground engineering project (with the designed gas processing capacity of 60 × 108 m3/a) is characterized by high processing rate of each unit, complex process control, large construction load, restricted construction site and tight schedule. Based on the traditional engineering construction mode, however, it is difficult to complete the project design and construction within 16 months. In view of this, the design concept of unit large-scale modularization was introduced to implement “normalized design, scale purchase, factory-like prefabrication and modularized construction” and develop the modularization technology of large-scale surface engineering construction. This modularization technology is performed as follows. First, the modularized units are laid out reasonably according to the technological process. Second, the layout of modularized units is usually superimposed in the multi-layer framework. Third, those equipments with the same or similar operational modes, medium properties, functional characteristics and installation requirements are concentrated in the pattern of a module. Fourth, escape passageway is specially set up. Fifth, room for installation, maintenance and repair of large equipments is reserved. And sixth, transportation and hoisting requirements of modules are taken into consideration sufficiently. This technology is contributive to the improvement of design quality, effective shortening of design period, reduction of field working load, decrease of safety management risk of on-site installation, increase of production efficiency, conservation of land occupation and diminishment of construction investment. It plays a reference role in the modularized construction of surface engineering of similar large projects.

Bioremediation techniques-classification based on site of application: principles, advantages, limitations and prospects.

Environmental pollution has been on the rise in the past few decades owing to increased human activities on energy reservoirs, unsafe agricultural practices and rapid industrialization. Amongst the pollutants that are of environmental and public health concerns due to their toxicities are: heavy metals, nuclear wastes, pesticides, green house gases, and hydrocarbons. Remediation of polluted sites using microbial process (bioremediation) has proven effective and reliable due to its eco-friendly features. Bioremediation can either be carried out ex situ or in situ, depending on several factors, which include but not limited to cost, site characteristics, type and concentration of pollutants. Generally, ex situ techniques apparently are more expensive compared to in situ techniques as a result of additional cost attributable to excavation. However, cost of on-site installation of equipment, and inability to effectively visualize and control the subsurface of polluted sites are of major concerns when carrying out in situ bioremediation. Therefore, choosing appropriate bioremediation technique, which will effectively reduce pollutant concentrations to an innocuous state, is crucial for a successful bioremediation project. Furthermore, the two major approaches to enhance bioremediation are biostimulation and bioaugmentation provided that environmental factors, which determine the success of bioremediation, are maintained at optimal range. This review provides more insight into the two major bioremediation techniques, their principles, advantages, limitations and prospects.

Manufacturing and evaluation of Large-scale Composite Bumper System for bridge pier protection against ship collision

An innovative Large-scale Composite Bumper System (LCBS) for bridge piers against ship collision was recently proposed at Nanjing Tech University. The modular segment of LCBS is made of Glass Fiber-Reinforced Polymer (GFRP) skins, GFRP lattice webs, Polyurethane (PU) foam cores and ceramic particles in which Vacuum Assisted Resin Infusion Process (VARIP) is adopted in the manufacturing process. This novel bumper system offers several remarkable advantages, such as: self-buoyancy in water, modular fabrication of segments, efficiency for on-site installation, excellent corrosion resistance, as well as ease in replacing damaged segments. In this paper, the manufacture procedures as well as the installation process of LCBS were introduced. An in-depth analysis of performance evaluation of LCBS was then conducted for a real cable stayed bridge using a nonlinear explicit dynamic finite-element analysis program (LS-DYNA). The simulation results indicated that LCBS can effectively increase the impact time of ship-bridge collision, and reduce the peak collision forces to a non-destructive level, leading to a good effect in energy dissipation. The results suggest that LCBS is an effective bumper system for protecting bridges and ships in ship-bridge collisions.

Adapative Load Anti-islanding Method of Large Distributed Photovoltaic Power Grid

A large number of distributed photovoltaic power grid, islanding problems become more prominent. This paper first analyzes some existing anti-islanding scheme, and analyzes its advantages and disadvantages. Then, this paper proposes adaptive anti-islanding scheme by using the load, i.e. load automatic switching, changing the characteristics of the whole load, make the passive anti-islanding without dead-zone. Then using PSCAD simulation of the program, to verify the usefulness of the proposed scheme. To minimize the distributed photovoltaic power grid investment, saving the scheme relies on a new generation of distributed photovoltaic (pv) grid interface device. Then the paper introduces the overall structure and function of the device configuration, the device not only can solve the problem of area of backup protection, also save on investment, convenient for on-site equipment installation and maintenance, for the widespread promotion of distributed photovoltaic power grid to lay a solid foundation.

W-band photonic-wireless link with a Schottky diode envelope detector and bend insensitive fiber.

The performance and potential of a W-band radio-over-fiber link is analyzed, including a characterization of the wireless channel. The presented setup focuses on minimizing complexity in the radio frequency domain, using a passive radio frequency transmitter and a Schottky diode based envelope detector. Performance is experimentally validated with carriers at 75-87GHz over wireless distances of 30-70m. Finally the necessity for and impact of bend insensitive fiber for on-site installation are discussed and experimentally investigated.

Piezoelectric energy harvester for public roadway: On-site installation and evaluation

This paper presents the development of a novel piezoelectric energy harvester (PEH) to harness the great amount of energy wasted by the vehicles on public roadways was described. The PEH is designed to convert the deformation energy induced by moving vehicle from pavement into electrical energy. The prototype harvester consists of PZT piezoceramic disks sealed in a protective package is developed. Six prototype PEHs were fabricated and installed in real pavement to evaluate the feasibility of this application. The electric productivity of the installed harvesters was evaluated by measuring the output voltage and current generated under real traffic. Instant and average power outputs are calculated from the measured waveforms of output voltage and current. The analysis of the testing results shows that the electrical productivity of the energy harvesters are highly relevant to the axle configuration and magnitude of passing vehicles.

Seismic performance of special reinforced concrete coupling beams with diagonal reinforcement and headed bars

Special reinforced concrete coupling beams in high-seismic-risk regions require specific diagonal bundled reinforcement details that must be strictly followed to ensure proper structural performance. However, when these details are applied to coupled shear wall structures, the coupling beams' width must match the width of the walls, resulting in a complicated rebar layout and difficulty in on-site installation. Especially when applied with special shear wall structures, the joint between the coupling beam and the shear wall results in extremely complex reinforcement details that are almost impossible to install on site. With a view to overcoming such problems, this paper evaluates and reports on seismic resistance performance tests performed on coupling beams with a single diagonal reinforcement bar together with headed bars (DHB) reinforcement details, as a proposed alternative solution. Test results show that the test specimen HB75, in which the headed bars substituted for 75% of the capacity of the diagonal reinforcing bundled bars, had superior ductility and energy dissipation capability, as well as lower strength and stiffness degradation compared to other test specimens. Thus, this research indicates that the headed bars can be a practical alternative to hoops of diagonal bundled bars for confining concrete in coupling beams.

An LED-based luminaire for badminton court illumination

In this paper, the design of a luminaire for badminton court illumination is demonstrated from concept through computer simulation, construction trials, on-site installation, comparison with simulations and, finally, evaluations of the illuminated environment before and after the installation of the luminaires. The luminaire is composed of two high-performance light-emitting diode lighting modules, volume scattering diffusers with a one-shot transmittance higher than 70% and a reflecting cavity with a reflectivity higher than 85%. The luminaire has three different exit faces forming three Lambertian-like light sources with low luminance so as to reduce glare to the players when looking at the flight of the shuttlecock. Under similar total electric power consumption, compared to the original traditional lighting, the average illuminance on the ground is enhanced by about 300% and the uniformity is obviously improved. A questionnaire was issued to players before and after the installation of the new light-emitting diode luminaires. The new installation gained much more positive responses for brightness, comfort and number of usable courts from the players than the old installation.

Development of the life-cycle economic and environmental assessment model for establishing the optimal implementation strategy of the rooftop photovoltaic system

To maximize the life-cycle economic and environmental performance of the rooftop pho­tovoltaic (PV) system in real projects, it is necessary to consider several factors such as regional climate factors (i.e., geographical and meteorological factors) and building characteristics (i.e., on-site installation factors, rooftop area limit, and budget limit). Towards this end, this study aimed to develop the life-cycle economic and environmental assessment model for establishing the optimal implementation strategy of the rooftop PV system. The robustness and reliability of the developed model were evaluated in terms of two perspectives: (i) for the effectiveness of the optimal solution, the optimization results were generated by considering the regional climate factors and building characteristics. Namely, the results for SIR25 (saving to investment ratio at year 25), which was set at the optimization goal, were 2.540 (Busan, southern part of South Korea), 2.485 (Daejeon, central part of South Korea), and 2.266 (Seoul, northern part of South Korea), respectively; and (ii) for the efficient computation time, the time required for determining the optimal solution was only 27 seconds. The developed model can be used to easily and accurately assess the life-cycle economic and environmental performance of the rooftop PV system in the early design phase.

Eco-efficiency analysis of the life cycle of interior partition walls: a comparison of alternative solutions

This paper presents an eco-efficiency analysis of the entire life cycle of 10 alternative solutions that can be used for interior partition walls that are variants on five building solutions commonly used in Spain (gypsum plasterboard system, hollow clay brick system, hollow concrete block system, autoclaved aerated concrete block system and gypsum block system). The full life cycle was considered for each of these interior partition wall solutions, which includes raw materials acquisition, transportation to the construction site, on-site installation and demolition and waste management at their end-of-life. For the environmental analysis, standard EN 15804, which provides product category rules for developing environmental declaration of construction elements based on the Life Cycle Assessment methodology, was applied. Main contributions for this application were the development of a comprehensive life cycle inventory adapted to the case study and the sensitivity analysis conducted for evaluating the influence of the characterisation factors in the environmental impact indicators. For the economic analysis, the costs of the life cycle of each solution were obtained. Finally, with the aim of selecting the alternatives with the best behaviour from both perspectives, an eco-efficiency study was conducted, the results of which showed that the gypsum plasterboard system and hollow concrete block system are the ones that combine the best environmental and economic performance. This is mainly due to the fact that they combine the lowest contribution to the impact for all the categories that were analysed, with lower life cycle costs.

Large scale test of a novel back-pass non-perforated unglazed solar air collector

This paper describes large scale tests conducted on a novel unglazed solar air collector system. The proposed system, referred to as a back-pass solar collector (BPSC), has on-site installation and aesthetic advantages over conventional unglazed transpired solar collectors (UTSC) as it is fully integrated within a standard insulated wall panel. This paper presents the results obtained from monitoring a BPSC wall panel over one year. Measurements of temperature, wind velocity and solar irradiance were taken at multiple air mass flow rates. It is shown that the length of the collector cavities has a direct impact on the efficiency of the system. It is also shown that beyond a height-to-flow ratio of 0.023 m/m³/hr/m2, no additional heat output is obtained by increasing the collector height for the experimental setup in this study, but these numbers would obviously be different if the experimental setup or test environment (e.g. location and climate) change. An equation for predicting the temperature rise of the BPSC is proposed.

Productivity-Based Management System for Offsite Manufacturing: Case Study of Noralta Lodge

Large-scale projects entail a zero-tolerance policy in regards to on-time project delivery and project quality. Severe winter conditions in Canada challenge conventional on-site construction activities and raise the risk of project delays and deficiencies. Industrialized (modularized) construction stands as an alternative that provides high quality products in a timely manner. Moreover, modular construction offers manufactured building components in a controlled environment, which ensures that quality standards remain consistent regardless of weather conditions. Once manufactured, modular units are then shipped to the site to be assembled. Two major geographical phases are common in offsite construction: the manufacturing phase, and the on-site installation phase. Consequently, management teams face challenges related to productivity and optimum work sequence in both phases. Traditional project planning and control methods consider the duration of a task as a static entity resulting from the direct relationship between the sizes of the crews on-site and labour productivity. Learning curves, skill-based tasklabour matrices, and resource levelling techniques are factors that imply the dynamic nature of construction tasks; delays in one task may affect other subsequent tasks both directly and indirectly. The Productivity-Based Management System (PBMS) provides opportunities to increase the production rates of task duration, and decrease actual task duration. The proposed research introduces a framework for a PBMS to manage and control the on-site phase of modular construction. In this research, the PBMS is developed, implemented, and then applied to a 1,700- bedroom workforce camp in Fort McMurray, Alberta, Canada.

Seismic retrofitting of an HV circuit breaker using base isolation with wire ropes. Part 1: Preliminary tests and analyses

This paper briefly describes the design and characterisation of a base isolation system that protects HV ceramic circuit breakers during seismic events. This qualifies them to the European standard CEI EN 62271-207. The solution is based on an innovative application of wire rope isolators. Preliminary numerical analyses and tests were performed on a typical HV circuit breaker and demonstrated the effectiveness of the proposed isolation system in reducing seismic demand. The results were also validated using a shaking table, which is described in an accompanying paper. The on-site installation of this system in several Italian substations has finally proved simple enough to upgrade the equipment for seismic protection.

Innovative CFRP-Prestressing System for Strengthening Metallic Structures

An innovative retrofit system to prestress carbon fiber reinforced polymer (CFRP) plates and attach them to existing metallic beams was developed (patent number CH 706 630 B1) and tested. The system does not require any glue between the CFRP plates and the beams; therefore, surface preparation is not necessary, which reduces the time and cost of retrofitting. The proposed prestressed unbonded reinforcement (PUR) system includes a pair of mechanical clamps that function based on friction. Each clamp can simultaneously hold and attach three CFRP plates to the beam. The design considerations of the clamps, which are the most important elements of the PUR system, were explained. The system has a trapezoidal configuration that offers an easy on-site installation and uninstallation procedures without residual damage on the metallic beam. Three 5-m-long steel beams were statically tested until failure, including one reference unstrengthened beam and two beams that were strengthened with 15% and 31% CFRP prestress levels. A considerable increase in the yielding and ultimate load capacities of the retrofitted beams was achieved. The ultimate load-carrying capacity of the strengthened beams with 15% and 31% CFRP prestress levels increased by more than 23% and 31%, respectively, compared to that of the reference specimen. A finite-element (FE) model was created to simulate the behavior of the retrofitted beams. Next, the FE results were compared with those from the experiments.