Roof

The growing world consumption of wood in civil construction is evident, especially in structural roofing systems. Despite being from a renewable source, its rational and intelligent use is of vital importance in the execution of structural designs. Because it is a system that is recognized worldwide in the design of trussing roof structures, there are several empirical assumptions for structural calculation. To reduce timber consumption, some tile manufacturers suggest a 10% (6°) slope between chords. However, after simulations of 11 slopes with angles from 5° to 15°, the timber consumption was inversely proportional to the slope, reaching a 90% difference between extreme angles. The method used to obtain the results was software designed according to the routines prescribed by the new draft standard of ABNT NBR 7190 (2021). Considering a prefabricated truss with 5 cm thickness sections, the design criterion was that of minimum height, increasing by 0.10 cm until all checks were sat...

The use of an equivalent continuum for a rock mass is not always suitable for situations, where the failure is structurally controlled by discontinuities as in the case of wedges in the tunnel roof. In these instances, discontinuum approaches are usually preferred. Rock joints that are filled with soft infill are likely to be the weakest planes in a rock

The use of an equivalent continuum for a rock mass is not always suitable for situations, where the failure is structurally controlled by discontinuities as in the case of wedges in the tunnel roof. In these instances, discontinuum approaches are usually preferred. Rock joints that are filled with soft infill are likely to be the weakest planes in a rock

The paper highlight on the waterproofing materials used for real project examples involving real problem mainly with roof related leakage mostly happened in Malaysia and some cases in the United Kingdom. The study outlines typical problem facing with the building leakage within the humid warm tropical climate as well as highlighting some obvious leakage scenario found within the opposite northern hemisphere’s climate in the UK. It also tabling the list of practical waterproofing solution done for each of the seepage problem from the real life case studies highlighting the technique and suitable best materials and products used. The paper target to help the construction players i.e. the maintenance team, building owner as well as the designer to identify the correct steps especially when choosing the right waterproofing materials in dealing with the building’s rectification work typically dealing with the building leakage syndrome problem.

Rainwater harvesting is implemented appropriately by striving to use costs that are quite cheap and efficient, but still has many benefits for meeting clean water needs. In this study, the rainwater harvesting model to be analyzed was using the cistern method. The advantage is that it is easier to apply, the amount of water collected is quite large, and it does not require a large area of land. By implementing a culture of harvesting rainwater, can get several benefits, including reducing runoff which can prevent the UTU campus area from inundation and flooding. The average volume of rainwater that can be harvested using a 5-year return period is 110581.12 liter/day with an average volume of water requirements of 7452.09 liters/day. From the results of the rainwater harvesting analysis, it can be concluded that this method is capable of being applied where the analysis results show that the harvested rainwater can meet the water needs of users on the Teuku Umar University campus. In...

Giard, Agnès. 2015. « La Jeune Fille sacrifiée sous le toit : étude d'un rituel de passage des frontières », dans Marc-Olivier GONSETH (dir.). Imagine Japan, Neuchâtel, Musé d'Ethnographie de Neuchatel, 2015, p. 222-228.

......................................................................................................................................................................................... RESUME : Quel est le lien entre une chevelure humaine suspendue au sommet d'une charpente et la signature du traité d'amitié entre la Suisse et le Japon  ? Exogène par essence, la culture japonaise attribue aux entités «  étrangères  » le pouvoir de revivifier et de rendre heureux. Mais les puissances venues d'ailleurs peuvent également exercer une influence néfaste qu'il s'agit de conjurer à l'aide de dispositifs stratégiquement placés aux frontières, à l'endroit même où le domaine du monde pacifié rencontre celui de l'altérité. C'est également lors des périodes-charnières, au moment de célébrer le passage d'une année à l'autre, que sont inaugurées les alliances. Le 6 février 1864, jour de la signature du traité d'amitié entre la Suisse et le Japon, Aimé Humbert n'est donc pas le seul à se réjouir. Le Japon tout entier semble communier avec lui dans la joie  : ce jour, qui correspond aux préparatifs des fêtes du Nouvel An, est celui durant lequel les projets en cours doivent être achevés, les choses anciennes éliminées afin d'initier un nouveau cycle. Humbert note que ce jour-là ont lieu les cérémonies de faîtage qui marquent la fin des constructions de charpentes. Elles sont célébrées suivant des modalités particulières  impliquant la consécration rituelle d'une chevelure de femme, porteuse de tout le poids d’inquiétude lié à la résurgence des défunts dans ce monde. Les racines de ce rituel plongent dans un corpus de contes horrifiques, révélateurs du rapport ambigu que les vivants entretiennent avec les morts et les habitants du Japon avec ces grandes puissances venues de l'autre côté de la mer…

Green roof system is one of sustainable approach for energy consumption reduction and improving the aesthetic value of the built environment. The system has been adopted by most of developed countries; and in Malaysia, research on green roof studies are quite evolving however the implementation of the system is slow due to some perceptions and obstacles. Green roof has potential on providing benefits such as reduction on the urban heat island effect, reduces temperatures, pollution and improves the attenuation of stormwater. This paper will highlights on a preliminary review of the implementation green roof system in Malaysia and explores the performances of Malaysian green roof in order to highlight the performance of green roof under tropical climatic conditions using local configurations.

Roof bolting is the most popular type of support for underground mines’ workings. However, in Polish coal mines it is used only as a supplementary support. To raise the effectiveness and economic score of horizontal development works, JSW (Jastrzębska Spółka Węglowa) started a project to introduce the independent rock bolting support in its mines. The key element of the project is the monitoring of mine workings supported with roof bolting, as appropriate control allows one to ensure a proper level of safety. The following work presents a monitoring system for mine working supported with roof bolting applied in the project, as well as results of the measurements obtained using this system. The aim of the monitoring was to prove that independent roof bolting provides a proper level of safety and thus is applicable in conditions of Polish underground coal mines, particularly Budryk mine. It was to be proved by the evaluation of data obtained from instrumented bolts, extensometers of d...

The integration of vegetation, irrigation and natural materials like soil with the roof structure of a building may be a functional, ecologically sound, and cost-effective design strategy for reducing or dampening the effect of heat gain from solar radiation. This experiment explores the possibilities of reducing the energy consumption of buildings in the arid (hot and dry) climate of Phoenix, Arizona by analyzing the effect of solar radiation on different roof systems. Four roof systems were tested and compared against a reference case (standard roof). The test boxes were instrumented in order to measure temperature at a number of locations within the enclosed space as well as at layers of the roofing system. The purpose was to observe and analyze the effectiveness of the four test roof systems as compared to the standard roof. Analysis of the temperature data acquired from a 24 hour period in early summer 2005 provides clear indicators of the cooling effect of an irrigated planted roof system, while non-irrigated systems may turn out to be counter productive to the goal of reducing heat gain to the interior resulting from solar radiation on the roof.

This paper presents the thermal analysis of the natural greenhouse dryer which has the capacity of 1kg. The dryer was fabricated and tested for the main parameters of relative humidity, drying temperature, product's surface temperature, black paint temperature, roof temperature of the dryer and temperature correlation with solar radiation. In relative humidity measurement session, it is almost the same in relative humidity inside and outside of the greenhouse dryer. In drying temperature measurement results, while the open sun drying is around 40°C, the greenhouse dryer reach 50°C as a maximum result for all three test products. According to the test results, the product's surface temperature of open sun drying was 45°C and that of greenhouse was 53°C during testing. At the comparison of black paint and roof surface temperature, deviation is around 45% in greenhouse.

A jointed rock mass presents a more complex design problem than the other rock masses. The complexity arises from the number (greater than two) of joint sets which define the degree of discontinuity of medium. The condition that arises in these types of rock masses is the generation of discrete rock blocks,of various geometries. They are defined by the natural fracture surfaces and the excavation surface. Stability problems in blocky jointed rock are generally associated with gravity falls of blocks from the roof and sidewalls. Whereas for block defined in the crown of tunnel,the requirement is to examine the potential for displacement of each block under the influence of the surface tractions arising from the local stress field and the gravitational load,in this paper various types of wedge formation in the crown of tunnel due to intersection of joint sets with various dip were examined. The state of stability of the wedge was then assessed through the factor of safety against roof failure. Following that the formed wedges in New York city and Washington D.C tunnel crowns was investigated with limit equilibrium analytical method and by use of Hoek and Brown failure criterion. The obtained results from analytical method corresponded with field observation.

This paper presents an analytical study on the serviceability of reinforced concrete gable roof beams with openings of different sizes, based on an experimental study which includes 13 concrete gable roof beams with openings under static loading. For deflection and crack widths under static loading at service stage, a developed unified calculation procedure has been submitted, which includes prismatic beams with one opening subjected to flexure concentrated force. The deflection has been calculated with two methods: the first method calculated deflections via relevant equations and the second was Direct Stiffness Method in which the beam is treated as a structural member with several segments constituting the portions with solid sections and those with sections crossed by the opening. The crack width was calculated with the ACI code’s equation with a proposed magnification factor equal to 1.125. The analytical results were compared with the experimental ones and a good agreement was...

For low‐rise buildings in equatorial region, the roof is exposed to solar radiation longer than other parts of the envelope. Roofs are to be designed to reject heat and moderate the thermal impact. These are determined by the design and construction of the roofing system. The ...

Green roofs can be an effective tool for sustainable urban drainage, since they reduce and retain runoff by delaying its peak. Most studies analysing the retention capacity of green roofs are usually referred to a specific place and roof condition and do not consider the possibility that the roof could be partially pre-filled from previous rainfalls at the beginning of the given event. The aim of this paper is to develop an analytical probabilistic approach to evaluate green roof performance for stormwater control in terms of runoff that could be applied for different sites and climate conditions. To this end, the possibility that the green roof retention capacity could not be completely available owing to pre-filling from previous rainfall events has been considered and equations for an optimum green roof design, relating the runoff average return interval to the water retention capacity, have been proposed. The influence of parameters affecting the runoff process has been examined...

The roofs of houses located at middle latitudes receive significant solar radiation useful to supply their own energy demands and to feed back into the urban electricity network. However, solar panels should be properly integrated into roofs. This study analyzed roof geometry and integrated solar performance of Photovoltaic, thermal-photovoltaic, and hybrid solar collection technologies on dwelling cases selected from a sample of recent housing developments in Concepción, Chile. Hour-by-hour energy generation estimates and comparisons with demand levels were calculated for representative days during seasons of maximum, minimum as well as mid-season. These estimates took into account the roof tilt and orientation effects also. Trnsys@ software was used to determine electricity supply and F-Chart tool for thermal energy supply. The results show five times more panels can be placed on the largest and most regular shaped roof sections than on those with the smallest and most irregular s...

The paper presents the experimental tests carried out in the boundary layer wind tunnel (BLWT) for the design of large roofs of the new Olympic stadium (Karaiskaki) in Pyraeus (Greece), Manfredonia (Italy) and “Delle Alpi” of Turin (Italy). In addition, a report about some results of the T.D. dynamic response analyses performed on the Karaiskaki structure and on the Olympic

Bangunan dengan konsep green architecture meminimalkan dampak buruk global warming terhadap lingkungan alam dan manusia.Selain itu tempat hidup menjadi lebih baik dan lebih sehat denganmemanfaatkan sumber energi dan sumber daya alam secara efisien dan optimal.G reen roof merupakan konstruksi atap pada bangunan yang dilapisi tanaman. Aplikasi g reen roof sudah banyak diterapkan di berbagai negara salah satunya di Singapore. Marina Barrage adalah sebuah bangunan bendungan di Singapore yang berfungsi sebagai tempat penampungan air, pengendali banjir, pengolahan air bersih dan tempat wisata.Bangunan Marina Barrage ini menggunakan aplikasi green roof. Tujuan dari penelitian ini adalah untuk mengetahui konsep desain dan fungsi dari green roof pada bangunan Marina Barrage serta sejauh mana aplikasi green roof tersebut berpengaruh terhadap lingkungan sekitarnya.Metode penelitian yang digunakan adalah deskriptif kualitatif. Green roof pada bangunan Marina Barrage dapat digunakan sebagai temp...

Normal 0 21 false false false TR X-NONE X-NONE MicrosoftInternetExplorer4 The green areas that should have been in the urban have been replaced with the concrete structures because of the  intensive housing activities and work places constructions. Insufficient green areas are gradually changing the  climate of urban. Air pollution has become a major problem of the urban. Thus, green roofs have become a necessity  for architecture. In this study, firstly the concept of green roof, the advantages and disadvantages of green roofs, their  applicability and its place in the design of the structure as an architectural element are tried to be elaborated. Then,  the green roof samples in Turkey and other countries are analyzed and compared. Keywords: Green roofs, sustainability, ecological architecture

Among all United States underground coal fields, those in Illinois have the highest rate of roof fall events due to their weak and severely moisture sensitive roof rock units. Rockmass characterization is the key initial step in designing safe and economical roof control measures in underground coal mines. In this study, a performance-based roof rockmass characterization is investigated. The geologic conditions as well as underground mine geographic specifications, roof fall analysis, mining method, utilized supplemental roof control measures, and geotechnical properties of roof rock units were considered to link the roof performance to rockmass characterization. The coal mine roof rating (CMRR) rockmass characterization method was used to evaluate the roof conditions and roof support design for an underground coal mine located in the Illinois Coal Basin. The results of several mine visit mappings, laboratory test results, and geotechnical issues and concerns are presented and discussed. The roof support designs are analyzed based on the rockmass characterization and are compared with the observed performance. This study shows that (1) CMRR index is a reasonable method for characterizing roof rockmass; (2) moisture sensitivity and bedding strengths in the horizontal direction are essential parameters for roof support design in mines with weak roof conditions; and (3) the applicability of the analysis of roof bolt system for roof support design of the studied mine is questionable.

In recent years, a great deal of interest has been created regarding the use of ferrocement in constructing roofs for new buildings and utilizing this material in the repair of existing structures. In order to get the benefits of ferrocement (e.g. low cost), accurate methods of analysis and design have to be used. Finite strip method appears to have great potential in predicting the static response of the composite (multi-layered) structural elements. Application of a high precision finite strip modeling in the analysis of ferrocement shell roof structures is investigated in this paper. Comparison with experimental results from other publications is included.