Demolition Work Research Articles

Reuse of Ceramic Demolition Waste in the Reconstruction of Planked Timber Floor Slabs

The aim of this work, mainly an experimental study, is to develop a new infill piece by reusing ceramic waste from demolition works. The piece is intended for use in floors as part of the rehabilitation of a type of building in which such materials were originally used, and forms part of the repair process of infill slabs characteristic of domestic architecture. It also enables the reuse of existing wooden beams that still retain their strength capacity. Various test models to reproduce the geometry and structural characteristics of these slabs were developed, and experiments with the proportions of mortar and geometries were performed to achieve the required strength capacity for their use on site. As a result, an infill piece was produced with a strength capacity of up to 457 kgf, which exceeds the values ​​required for prefabricated concrete slabs according to current regulations. Finally, it should be noted that this new piece contributes to the conservation of the original vertical supporting structure based on masonry walls, while the horizontal structure is rendered lighter thanks to these new slabs.

Waste Management of Emergency Construction Work. Case Study: 40 Dwellings in Seville (Spain)

Eco-efficient rehabilitation of buildings and neighbourhoods should include strategies to reduce the potential environmental impact of buildings under consideration for demolishment. In this case, good construction and demolition (C&D) waste management can represent a doubly eco-efficient approach: advantage is taken of much of the building and the volume of waste is reduced during construction and demolition work. Construction and demolition waste management in emergency situations is a subject yet to be studied in the construction sector. This kind of work, although not very common, involves major building damages and the need for punctual, partial or total demolitions. The amount of C&D waste can be a major problem to deal with, and its management during the critical first phases can determinate the progress of the rehabilitation. Conditioned by a greater number of factors than normal construction works, the lack of time for the identification, quantification, and evaluation of C&D waste renders this type of extremely useful study. In this work, from the case study of the emergency repair of a residential building of 40 dwellings in Seville (Spain) seriously affected by a soil displacement, Generated C&D waste are identified and the waste reduction techniques used are shown. These techniques contributed to achieve the planned objectives and to control in advance the cost. Finally, the most important data, C&D waste quantification and the managing cost are presented in order to serve as reference for similar circumstances in the future because there areno clear references to be used.

An Alternative to Conventional Rock Fragmentation Methods Using SCDA: A Review

Global energy and material consumption are expected to rise in exponential proportions during the next few decades, generating huge demands for deep earth energy (oil/gas) recovery and mineral processing. Under such circumstances, the continuation of existing methods in rock fragmentation in such applications is questionable due to the proven adverse environmental impacts associated with them. In this regard; the possibility of using more environmentally friendly options as Soundless Chemical Demolition Agents (SCDAs) play a vital role in replacing harmful conventional rock fragmentation techniques for gas; oil and mineral recovery. This study reviews up to date research on soundless cracking demolition agent (SCDA) application on rock fracturing including its limitations and strengths, possible applications in the petroleum industry and the possibility of using existing rock fragmentation models for SCDA-based rock fragmentation; also known as fracking. Though the expansive properties of SCDAs are currently used in some demolition works, the poor usage guidelines available reflect the insufficient research carried out on its material’s behavior. SCDA is a cementitious powdery substance with quicklime (CaO) as its primary ingredient that expands upon contact with water; which results in a huge expansive pressure if this CaO hydration reaction occurs in a confined condition. So, the mechanism can be used for rock fragmentation by injecting the SCDA into boreholes of a rock mass; where the resulting expansive pressure is sufficient to create an effective fracture network in the confined rock mass around the borehole. This expansive pressure development, however, dependent on many factors, where formation water content creates a negative influence on this due to required greater degree of hydration under greater water contents and temperature creates a positive influence by accelerating the reaction. Having a precise understanding of the fracture propagation mechanisms when using SCDA is important due to the formation of complex fracture networks in rocks. Several models can be found in the literature based on the tangential and radial stresses acting on a rock mass surrounding an SCDA charged borehole. Those fracture models with quasi-static fracturing mechanism that occurs in Mode I type tensile failure show compatibility with SCDA fracturing mechanisms. The effect of borehole diameter, spacing and the arrangement on expansive pressure generation and corresponding fracture network generation is important in the SCDA fracturing process and effective handling of them would pave the way to creating an optimum fracture network in a targeted rock formation. SCDA has many potential applications in unconventional gas and oil recovery and in-situ mining in mineral processing. However, effective utilization of SCDA in such application needs much extensive research on the performance of SCDA with respect to its potential applications, particularly when considering unique issues arising in using SCDA in different applications.

INCE/J Vibration Measurement Manual for Buildings—Part 3: Measurement example of building vibrations

The environmental impact on humans in buildings is caused by ground-borne vibration from rail transit systems, road traffic, construction sites, and industrial plants. To estimate the effect of vibration on humans, it is necessary to measure the tri-axial vibrations in the vertical and horizontal directions in buildings specified in ISO 2631-2:2003 or “Vibration Measurement Manual for Buildings” publicized by the Technical Subcommittees on Environmental Vibration Evaluation of The Institute of Noise Control Engineering of Japan. In this measurement example of building vibrations, vibration measurement was carried out for eight hours in a three-story, wooden detached house adjacent to a construction site. The residents perceived discomfort or annoyance from the vibration caused by the demolition work at the construction site. Five vibration measurement devices recorded simultaneously the vibration accelerations on the floor of each story, the concrete substructure and the asphalt pavement surface near the substructure. The 1/3 octave band vibration accelerations of each floor were estimated by the vibration perception threshold range of the vibration measurement manual. The vibration amplifications caused by building structural resonance was evaluated as ratios and level differences in the vibration accelerations measured at the ground near the substructure and floors in the houses.

Could we predict airborne Aspergillus contamination during construction work?

Aspergillus fumigatus is a major opportunistic pathogen causing nosocomial infection. Hospital outbreaks of invasive aspergillosis have been associated with demolition and building construction. This study was designed to examine the impact of meteorologic factors and different periods of work on outdoor fungal airborne concentrations. The study was conducted at Necker Enfants Malades Hospital, a 650-bed teaching care hospital recently involved in a large construction program, including renovation, construction, and demolition. During the work phases, prospective external air samplings were performed 3 times a week, and meteorologic parameters were collected every day. Two hundred and one samples were collected. Aspergillus spp were found in 80.1% of samples, with a median concentration of 16 colony forming units (CFU)/m3. A significant increase in the colony count of molds occurred after demolition. In the multivariate analysis, factors associated with overall fungi concentration were the type of work construction and temperature. Elevated Aspergillus spp concentrations (>20 CFU/m3) were associated with higher temperature. Our findings underline the importance of environmental surveillance. According to our results we suggest that demolition work should be performed during the winter and fall seasons.

Identifying factors influencing demolition waste generation in Hong Kong

Abstract Among all construction activities, demolition normally generates the largest proportion of construction and demolition (C&D) waste, to which requires more importance being attached for effective management. Previous studies have attempted to understand demolition waste generation (DWG) but the understanding remains relatively insufficient, largely due to the erratic and poor quality data available. This research aims to identify factors impacting DWG by making use of a big dataset which has recently become available as a result of C&D waste management practices in Hong Kong. Using big data analytics, it is confirmed that DWG, demolition cost, and duration of conducting the demolition work are dependent on each other. It is also found that geographical location, building usage, and the public-private nature of a building project also have a significant impact on DWG in the Hong Kong context. Based on the correlations between DWG and these identified factors, stakeholders may introduce proper managerial or policy interventions to effectively minimize DWG. For example, public policy-makers may formulate more tailor-made regulations to attach more importance to the locations, usages and public-private nature, which have more potentials for demolition waste minimization.

Environmental Assessment of an Abandoned Briquette Factory – A Case Study at Nagymányok Area, Former Industrial Zone

Abstract The study is focused on environmental assessments of impacts by former briquette factory at the Nagymányok area in South Hungary. The (former) industrial zone is located in a northern valley of the Eastern Mecsek Mountains. Until the 1990s this company was the largest briquette factory in Hungary and the demolition works are still incomplete. former investigations were based on only five samples. our sampling sites were selected on the basis of the source of the contaminations and then we covered the whole area in equal distribution. We used the A1-F6 codes for the sample places. We have started from southwest to northeast. The samples were analyzed for Total Petrol Hydrocarbons (TPHs), Polycyclic Aromatic Hydrocarbons (PAHs) and for heavy metals. The area was heavily contaminated by TPHs and moderately heavy metals (such as Cu, Cr, Zn and Pb). Highest contaminant concentrations were found around the former industrial buildings, especially between the boiler-house and the coal-pillbox. In the industrial area the mean of the detected values is below the upper limit of the legal exposure values, but among the former industrial buildings higher (e.g. toxic level) concentration values were detected in multiple samples. Based on our investigation the pollutant can be transported by wind or by water on the surface (stream bed) or underground. The hazardous material can easily reach some part of the city, therefore reclamation is necesarry.

Demolition waste generation for development of a regional management chain model

Even though construction and demolition waste (CDW) is the bulkiest waste stream, its estimation and composition in specific regions still faces major difficulties. Therefore new methods are required especially when it comes to make predictions limited to small areas, such as counties. This paper proposes one such method, which makes use of data collected from real demolition works and statistical information on the geographical area under study. Based on a correlation analysis between the demolition waste estimates and indicators such as population density, buildings ageing index, buildings density and land occupation type, relationships are established that can be used to determine demolition waste outputs in a given area. The derived models are presented and explained. This methodology is independent from the specific region with which it is exemplified (the Lisbon Metropolitan Area) and can therefore be applied to any region of the world, from the country to the county level. Generation of demolition waste data at the county level is the basis of the design of a systemic model for CDW management in a region. Future developments proposed include a mixed-integer linear programming formulation of such recycling network.

Restoration of the Cercle de L’Ermitage in Epesses, Switzerland

In 1935, Alberto Sartoris transformed an old mill into a private club for artists: le Cercle de l’Ermitage. The young architect conceptualized the space as a manifesto of rationalistic architecture. The resolutely modernist choice of the intervention contrasted with the rural and bucolic existing building. In 1971, the work disappeared under fake rustic decoration and everybody considered it lost, only remaining one of the most famous axonometries of the Italian master. Forty-five years later, the work reappears miraculously while the space is under transformation into a private residence. The demolition work has revealed an unexpected amount of original elements, which will allow a faithful and rigorous restoration of the Cercle de l’Ermitage.

Risk Factors and Epidemiology of Coccidioidomycosis Demonstrated by a Case of Spontaneous Pulmonary Rupture of Cavitary Coccidioidomycosis.

A 31-year-old Hispanic male with no medical history was admitted for fevers, pleurisy, and cough after recent oral surgery and completing demolition and construction work in Juarez, Mexico. Imaging showed a 4.4 cm cavitary lesion and bilateral tree-in-bud opacities. Initial suspicion of bacterial infection confirmed with clinical improvement on culture specific antibiotics, but after discharge he returned with progression of symptoms and new dyspnea. Radiograph showed a pyopneumothorax. Chest computed tomography after thoracostomy showed worsening infiltrates and another cavitary lesion. Symptoms persisted despite addition of broad spectrum antibiotics. Surgical repair for persistent air leak was required. Weeks after discharge, cultures and serologies returned positive for Coccidioidomycosis immitis. Coccidioides species cause up to 30% of community-acquired pneumonia and incidental cavitary lesions in endemic regions. Symptoms are nonspecific yet usually involve fatigue, cough, and pleurisy. Most hosts have spontaneous resolution; however, certain demographics such as Hispanics and diabetics, later diagnosed in our patient, have higher morbidity. As seen with our patient, cavitary rupture and bronchopleural fistulas are rare occurring in 2.6% of cavitary lesions. High suspicion based on symptoms and host demographics is important to assist in early diagnosis and treatment to avoid and treat this common pathogen's presentations.

4腕式極限作業ロボットOCTOPUSの開発

In this paper, a four-arm four-crawler advanced disaster response robot called OCTOPUS is developed. Disaster response robots are expected to be capable of both mobility and workability. To balance environmental applicability with the mobility and workability, OCTOPUS is equipped with a mutual complementary strategy between its arms and crawlers. The four arms conduct complex tasks while ensuring stabilization when climbing steps. The four crawlers translate rough terrain while avoiding toppling over when conducting demolition work. OCTOPUS is hydraulic driven and teleoperated by two operators. To evaluate the performance of OCTOPUS, we conducted preliminary experiments involving climbing high steps and removing attached objects by using the four arms. The results showed that OCTOPUS completed the two tasks by adequately coordinating its four arms and four crawlers and improvement in operability needs.

Organization of engineering works during demolition of a road section

When using explosive ordnance for the demolition of elements, materials and facilities, organization is very important in the preparation of works as well as during demolition itself. In the Army of Serbia, for this kind of works, there are specialized expert units within Land Forces engineering battalions or brigades. The organization of the engineering work given in the article is a purposeful solution, regarding the use of movable property and stress imposed on people as well, when performing demolition of a concrete structure - road section. Lack of literature is a big drawback, especially lack of norms for demolition works. Except for some unofficial lectures for internal use, most of the literature dates back to the seventies or early eighties. A special emphasis in this paper is given to the application of protective measures in the use of explosives.

Tasks and Problems in the Buildings Demolition Works: A Case Study

In Poland, it often happens that construction objects are subject to demolition work for different reasons. Demolition, according the Construction Law, is defined as a type of construction works and, as such, represents a particular type of construction project. As in other construction projects, a very important phase, in addition to execution of the works, is to prepare, design and plan demolition works. Some demolition activities are covered by appropriate regulations and can be described as typical. On the other hand the technical side of demolition works depends on many factors such as: the type of building, its age, technical condition, type of construction, etc. This article covers the analysis of the stages and tasks in the preparatory phase of the building demolition. This work will also present a description of the tasks carried out during the demolition works based on the example of a historic tenement house located in Krakow. This analysis aims to identify implementation problems and sources of risk that may occur during this type of construction work.

English

The handling of wastes remain a perpetual problem, all construction and demolition works and activities are confronted to this issue. Many investors, clients, construction and demolition professionals consider C&D waste management one of the most essential green construction practices in support to energy efficiency. In fact, there is a growing interest in sustainable waste management as potential stakeholders are pursuing innovative and integrated waste management and environmental strategies. Sadly, most traditional approach to reducing C&D waste is considered to be unsustainable as it lacks flexibility and long-term reliability. Thus, the move to a more sustainable society requires sophisticated approach to manage C&D waste, which incorporate feedback loops and focus more on processes, embodies adaptability and diverts waste from landfill disposal. This paper review current C&D waste management practices and propose a conceptual framework for optimising C&D waste management. The study adopts a Life-cycle (LCA) model based on C&D waste sustainability measure (LCASM) to justify the need for a green approach to C&D waste management. The central focus of the LCA model is to minimise C&D waste disposal and to enhance the application of 3Rs (reduce, reuse, recycle) concept. The study sought to determine whether this sustainable approach to C&D waste management is an opportunity or a new challenge. Recommendations are provided on how to enrich C&D waste management optimisation processes.

Organic compounds in concrete from demolition works

This study aims to verify the effect of physically removing the outer surface of contaminated concrete on total contents and on potential mobility of pollutants by means of leaching tests. Reclaimed concrete from 3 industrial sites in Sweden were included: A tar impregnated military storage, a military tar track-depot, as well as concrete constructions used for disposing of pesticide production surplus and residues. Solid materials and leachates from batch and column leaching tests were analysed for metals, Cl, F, SO4, DOC and contents of suspected organic compounds (polycyclic aromatic hydrocarbons, PAH, and pesticides/substances for pesticide production such as phenoxy acids, chlorophenols and chlorocresols, respectively). In case of PAH contaminated concrete, results indicate that removing 1 or 5 mm of the surface lead to total concentrations below the Swedish guidelines for recycling of aggregates and soil in groundwork constructions. 3 out of 4 concrete samples contaminated with pesticides fulfilled Swedish guidelines for contaminated soil. Results from batch and column leaching tests indicated, however, that concentrations above environmental quality standards for certain PAH and phenoxy acids, respectively, might occur at site when the crushed concrete is recycled in groundwork constructions. As leaching tests engaged in the study deviated from leaching test standards with a limited number of samples, the potential impact of the leaching tests' equipment on measured PAH and pesticide leachate concentrations has to be evaluated in future work.

Effects of acoustic characteristics of combined construction noise on annoyance

Abstract Because the acoustic environments of construction sites include multiple noise sources from various construction machines, it is necessary to consider the influence of combined noise on annoyance. The aim of this study is to examine the effects of the acoustic characteristics of combined construction noise on annoyance. Six construction machines, including machines for foundation work (pile drivers, earth augers, and payloaders) and demolition work (breakers, bulldozers, and excavators) were selected as noise sources in construction sites, and auditory experiments were designed to quantify the annoyance caused by the machines' individual and combined noise. The results show that both individual and combined noise correlate well with the equivalent sound level (LAeq), but that the annoyance caused by combined noise is significantly higher than the annoyance caused by individual noise when LAeq increases over 65 dBA. Among the psychoacoustic measures, loudness is the most important in determining the annoyance caused by individual noise, whereas both loudness and roughness significantly impact the annoyance caused by combined construction noise. Ranges of an optimum stationary-to-mobile machine noise ratio between two construction machine noises are suggested to minimize the annoyance caused by combined noise. Optimum stationary-to-mobile machine noise ratio ranges usually include 0 dBA when reference construction noise levels (e.g., pile driver or breaker) are lower than 60 dBA, whereas the stationary-to-mobile machine noise ratio should be greater than 5 dBA as construction noise levels exceed 65 dBA. These findings provide useful information to establish effective noise management plans for combined noise sources in construction sites.

Multivariate statistical assessment of predictors of firefighters' muscular and aerobic work capacity.

Physical capacity has previously been deemed important for firefighters physical work capacity, and aerobic fitness, muscular strength, and muscular endurance are the most frequently investigated parameters of importance. Traditionally, bivariate and multivariate linear regression statistics have been used to study relationships between physical capacities and work capacities among firefighters. An alternative way to handle datasets consisting of numerous correlated variables is to use multivariate projection analyses, such as Orthogonal Projection to Latent Structures. The first aim of the present study was to evaluate the prediction and predictive power of field and laboratory tests, respectively, on firefighters’ physical work capacity on selected work tasks. Also, to study if valid predictions could be achieved without anthropometric data. The second aim was to externally validate selected models. The third aim was to validate selected models on firefighters’ and on civilians’. A total of 38 (26 men and 12 women) + 90 (38 men and 52 women) subjects were included in the models and the external validation, respectively. The best prediction (R2) and predictive power (Q2) of Stairs, Pulling, Demolition, Terrain, and Rescue work capacities included field tests (R2 = 0.73 to 0.84, Q2 = 0.68 to 0.82). The best external validation was for Stairs work capacity (R2 = 0.80) and worst for Demolition work capacity (R2 = 0.40). In conclusion, field and laboratory tests could equally well predict physical work capacities for firefighting work tasks, and models excluding anthropometric data were valid. The predictive power was satisfactory for all included work tasks except Demolition.

English

The Malaysia construction industry generates a large quantity of construction and demolition waste nowadays. In the handbook for demolition work only comprised small portion of demolition waste management. It is important to study and determine the ways to provide a practical guide for the professional in the building industry about handling the demolition waste. In general, demolition defined as tearing down or wrecking of structural work or architectural work of the building and other infrastructures work such as road, bridge and etc. It's a common misconception that demolition is nothing more than taking down a structure and carrying the debris to a landfill. On many projects, 80-90% of the structure is kept for reuse or recycling which help the owner to save cost. Demolition contractors required a lot of knowledge and experience to minimize the impact of demolition work to the existing surrounding area. For data collecting method, postal questionnaires and interviews have been selected to collect data. Questionnaires have distributed to 80 respondents from the construction industry in Klang Valley. 67 of 80 respondents have replied the questionnaire while 4 people have interviewed. Microsoft Excel and Statistical Package for Social Science version 17.0 were used to analyze the data collected.

解体時の安全と信頼を確保するための「見える化」

解体時の安全と信頼を確保するための「見える化」

Financial Risk Estimation in Construction Contracts

Risk, as a factor adversely affecting the project, is taken into account as early as at the first stage of the investment process when the tender is won for a contract. The risk level, identified for a particular construction contract, is a serious factor influencing the decision about accepting the contract or not. The key issue is proper identification of contract risk. The risk factors which have a significant impact on the success of the project, and are most common ones, are then analyzed. The method of verification depends on the company's experience in the construction industry. The task of the article is to present the results of studies focused on separating and determining the frequency of financial risk factors in construction projects and their impact on project implementation. We have analyzed 30 construction projects (office buildings, production halls, educational buildings, demolition works, etc.) completed in north-western Poland. The degree of risk (planned and real) for the contract was set as a percentage in relation to the size of contract (costs in million PLN). The aim of the study was to verify the existence of relationship between the kind of structure, the size of contract, and the scope and degree of risk. Statistical approach has been used. This study is a prelude to determining the contract risks identification procedure (i.e., estimating reserves to be used in unforeseen circumstances) so that the company could be competitive, and the price offer to be provided to investors could be advantageous.