Multi-storey Construction Research Articles

Comparison of thermal comfort conditions in multi-storey timber frame and cross-laminated residential buildings

In recent years, timber construction systems have been increasingly used in multi-storey residential construction in Europe. In line with this international trend is the choice of the Trentino social housing company ITEA to build two five-storey multi-family apartment buildings in Trento (Italy) using two different timber wall systems. The two buildings are identical except for their structural system: timber frame (TF) and cross laminated timber (CLT). The design and the construction of these two buildings are the result of an international collaboration between ITEA and the Canadian social housing company Quebec Societe D’Habitation in order to evaluate and compare timber construction systems for social housing from the two countries. Since the two buildings have identical floor plans, layouts and finishes and differ only in their structural system, they present a unique opportunity for comparison of the two key forms of timber construction in terms of economic, engineering and indoor comfort issues. This paper investigates the difference in indoor conditions and analyse the achieved thermal comfort by measuring physical parameters and surveying the occupants’ perception. The two structural systems used for the buildings represent two widely used but fundamentally different forms of timber construction. The light timber frame is extremely lightweight, which gives the building low thermal mass and consequently low thermal inertia. This can lead to a lack of thermal comfort, particularly in summer, due to temperature fluctuations. Cross-laminated timber, used to form the timber shear walls in the south building, is a comparatively modern building component. Again, it can be highly prefabricated, and used with computer controlled cutting techniques to pre-cut openings for windows, doors and services to a high degree of accuracy. This system, known as ‘massive timber’, provides a higher thermal mass, if compared to the previous system. By means of indoor comfort monitoring and subjective questionnaires to the users’, it has been investigated to what extent this difference of thermal properties affects the indoor conditions provided and the final users’ satisfaction towards the thermal environment. This experimental campaign falls into a broader policy adopted by ITEA to engage closely with the performance of the buildings they build and manage, in accordance with an increasing interest globally in building performance assessment and post-occupancy evaluation (POE), whose main purpose is to investigate occupants’ reported levels of comfort and satisfaction and the degree to which they perceive their needs are being met by the building’s indoor conditions.DOI: http://dx.doi.org/10.5755/j01.sace.19.2.17531

Обоснование необходимости энергосбережения в многоэтажном жилищном строительстве

In this paper the main reasons and prerequisites for increasing the energy efficiency of multistorey residential buildings as a way of reducing the energy intensity of Country’s economy and reducing the anthropogenic impact on the environment were considered. The research methods were comprehensive, assessed, and include the literature review, the legislative and regulatory framework review, as well as the review and generalization of the accumulated native and foreign experience in the field of energy-saving. The high potential of the final energy consumption and the energy intensity of Russian construction sector redaction were noted, the main reasons were named. The necessity of carrying out energy-saving measures in multistorey housing construction was substantiated. In this paper the main problems facing the increase of energy efficiency of multistorey residential buildings, including the lack of scientific researches in this area and the low appeal of the research direction, caused by the features of market relations, were touched. State regulation was recognized as the most effective tool for overcoming existing problems. The main directions of further development were outlined. The need for further development of the regulatory and legal framework and a system of incentives and benefits for legal entities and individuals that effectively use energy resources was marked.

Numerical Modelling of Composite Floor Slabs Subject to Large Deflections

This paper is concerned with the ultimate behaviour of composite floor slabs. Steel/concrete composite structures are increasingly common in the UK and worldwide, particularly for multi-storey construction. The popularity of this construction form is mainly due to the excellent efficiency offered in terms of structural behaviour, construction time and material usage all of which are particularly attractive given the ever-increasing demands for improved sustainability in construction. In this context, the engineering research community has focused considerable effort in recent years towards understanding the response of composite structures during extreme events, such as fires. In particular, the contribution made by the floor slab system is of crucial importance as its ability to undergo secondary load-carrying mechanisms (e.g. membrane action) once conventional strength limits have been reached may prevent overall collapse of the structure. Researchers have focused on developing the fundamental understanding of the complex behaviour of floor slabs and also improving the methods of analysis. Building on this work, the current paper describes the development and validation of a finite element model which can simulate the response of floor slab systems until failure, both at ambient and elevated temperature. The model can represent the complexities of the behaviour including the temperature-dependent material and geometric nonlinearities. It is first developed at ambient temperature and validated using a series of experiments on isolated slab elements. The most salient parameters are identified and studied. Thereafter, the model is extended to include the effects of elevated temperature so it can be employed to investigate the behaviour under these conditions. Comparisons with current design procedures are assessed and discussed.

Nonlinear Seismic Analysis of Masonry Infill RC Buildings with Eccentric Bracings at Soft Storey Level

Eccentric bracings are used in steel structures for long time where it serves as lateral load resisting system and improve strength and stiffness of frame along with effective energy dissipation. In the present study, eccentric bracings are used as a means to reduce soft storey effect in masonry infill reinforced concrete (RC) building. Masonry infill buildings with open first storey are usual choice for almost every general multi-storey construction in India, despite the building's palpable vulnerability to strong ground motion earthquakes. Among other strengthening methods, eccentric bracings could be an advantageous scheme as it provides lateral stiffness and ductility to structure with greater economy and also provides free space for commuting of vehicle at soft storey level. It has been seen that introduction of soft storey in building leads to concentration of damage in that storey while the building suffers only slight damage. Hence, eccentric bracings in soft storey need to be designed in such a way that they act as fuse during major earthquake events. The seismic performance of eccentric bracings for a seven storey building located in Indian seismic zone – V as per Indian standard code 1893-2002 are investigated using nonlinear static pushover analysis. A parametric study involving parameters such as shape of eccentric bracing, area of section, amount of eccentricity etc. are performed for selecting the type of eccentric bracing. The results of pushover analysis, reported in terms of storey drift demand and collapse fragility curve, showed that buildings with eccentric bracings have lower drift demand and probability of collapse.

Viability of cross-laminated timber from UK resources

Cross-laminated timber is an innovative engineered timber product that can be used for almost all superstructure elements. It is typically produced from kiln-dried, fast-growing softwood timber. Currently there is no commercial production in the UK and hence the majority of cross-laminated timber used within the UK construction industry is manufactured in central mainland Europe and imported. This paper presents the key factors required for implementing a cross-laminated timber production and construction capability using available UK timber resource, thus offering a sustainable alternative to multi-storey steel and concrete construction. Further to this the structural performance of a cross-laminated timber product manufactured using a home-grown resource is compared with the current product imported from Europe. A series of standard design scenarios for multi-storey residential and education buildings in the UK have been considered and the structural design criteria reviewed for both products.

PUSHOVER ANALYSIS OF RC FRAME STRUCTURE WITH FLOATING COLUMN AND SOFT STORY IN DIFFERENT EARTHQUAKE ZONES

Open first story and Floating column are typical features in the modern multi-storey constructions in urban India. Such features are highly undesirable in buildings built in seismically active areas; this has been verified in numerous experiences of strong shaking during the past earthquakes like Bhuj 2001. In this study an attempt is made to reveal the effects of floating column & soft story in different earthquake zones by seismic analysis. For this purpose Push over analysis is adopted because this analysis will yield performance level of building for design capacity (displacement) carried out up to failure, it helps determination of collapse load and ductility capacity of the structure. To achieve this objective, three RC bare frame structures with G+4, G+9, G+15 stories respectively will be analysed and compared the base force and displacement of RC bare frame structure with G+4, G+9, G+15 stories in different earthquake zones like Rajkot, Jamnagar and Bhuj using SAP 2000 14 analysis package.

SEISMIC PERFORMANCE OF A RC FRAME WITH SOFT STOREY CRITERIA

Soft first storey is a typical feature in the modern multi-storey constructions in urban India. Social and functional need to provide parking space at ground level leads seismic vulnerability of such a building. The computer software usage in civil engineering has greatly reduced the complexities of different aspects in the analysis and design of projects. In the present study an attempt has been made to investigate the seismic behaviour of a multi-storey building with soft first storey. When subjected to seismic loads, it was observed that soft storey frames are less resistant when compared to infill frames.

Multi-storey timber construction and bioeconomy – barriers and opportunities

Multi-storey timber construction has been developed and promoted in Finland since the 1990s. Despite these efforts, the share of timber frames in multi-storey construction has remained very low. Construction business is also very resource intensive and accounts for a large share of greenhouse gas emissions. Increasing the use of renewable materials, mainly wood, in buildings, could make construction more sustainable and a part of bioeconomy. This study aimed at identifying barriers to the adoption of multi-storey timber construction, ways in which wood could compete with established solutions and possibilities for partly integrating construction into bioeconomy. Based on 18 interviews of representatives from the entire value chain, this study presents insights into introducing new solutions into a conservative field. Our results indicate that multi-storey timber construction could offer competitive solutions for more sustainable construction, even though barriers to its adoption still exist.

Athens Metro Line 3: Complex Tunnel Geometries

Complex tunnel geometries are very common during the design of urban tunnelling and especially metro lines. Relevant complexities were common during the construction of Athens Metro in Greece, where the need of giving access to trumpet areas, multi-storey underground constructions and transition zones produces special design requirements. Characteristic case histories are the trumpet area as well as the access gallery and chamber to Egaleo Station in the same extension, which are presented in the paper. In both cases, the real challenge was to give solution to underground complex constructions within short lengths of different tunnel profiles. In the first case, a triple-track tunnel splits to a single and a double-track one, while on the second one, a three-storey access gallery was constructed at the north side of Egaleo Station in order to give access for the construction of the station. According to the geology in the area, the Athenian schist was expected, completely weathered on the top and from low to medium strength deeper. The main criteria of the design was to result to a construction methodology such as to assure stability, low surface settlements and convergences, safety, quality and construction advance, within a realistic solution to the constructor. In both cases, the conventional tunnelling method was applied with success, not only regarding the final surface settlements which proved to be small, but also the speed and the convenience in applying on site the designed procedure.

Nonlinear dynamically automated excursions for rubber-steel bearing isolation in multi-storey construction

Conventional building design includes the concept of providing more stiff structural solution to withstand the lateral seismic loading. Introduction of flexible elements at the base of a structure and at the same time ensuring enough damping is the evocative alternate option to mitigate seismic hazard. The device that is capable to meet such criteria is known as isolator. This paper covers design of base isolators for multi-storey buildings in medium risk seismicity region and the structural response evaluation. Automated nonlinear models for dynamic response investigation have been configured. Finite element method (FEM) has been incorporated to envisage the structural response behaviors. Lead rubber bearing (LRB) and high damping rubber bearing (HDRB) have been chosen for inserting isolator link element in structural base. The nonlinearities of rubber-steel bearing have been duly considered. Linear static, linear dynamic and nonlinear dynamic analyses due to site-specific earthquake accelerogram are performed for both fixed based (FB) and base isolated (BI) buildings. Both time domain and frequency domain approaches have been carried out for dynamic solution. It was found that for multi-storey buildings, base isolation diminishes muscular amount of structural responses compared to the conventional fixed base (non-isolated) structures. Allowable higher horizontal displacement induces structural flexibility. The suggested isolation technique is competent to mitigate the structural hazard even under strong seismic vulnerability in optimum manner.

Effection of Relevant Parameters of Infilled Frame Wall on its Structural Lateral Stiffness

Statical analysis of infilled frame structure was conducted on 3D finite element models by means of software ANSYS10.0. Analyses on relevant parameters of infilled frame walls with or without openings have been carried out seperately, and it is found that the relevant stiffness of the model gradually increases with the ratio of the wall’s width to its height. However, the effection of the width to height ratio of the wall on its structural lateral stiffness becomes much smaller when the value of the width to height ratio is larger than 1.5. The effection can be basically ignored when the width to height ratio is larger than 1.8. It is investigated that the ratio of posts inertia moment to beams has great influence on model’s relevant stiffness. The relevant stiffness of frame structure decreases with the growth of the ratio of posts inertia moment to beams (I2/I1). For a long time, Filling Wall is widely used in multi-storey buildings and Civil Construction Structures, for its flexible architecture flats and large interior space, etc. However, because of the imperfection in analysis methods and the defects in model, pure- framework design is used in civil architectures, and the weight of filling wall is calculated by converting to the Line Load on the beam. According to the analysis of 5.12 Wenchuan earthquake[1], the early filling wall absorbs a large earthquake because of its stiffness, while its Adhesive Tensile Strength is low, which making the earthquake-damage to the filling wall is more serious than that to the frame structure. By analyzing the parameters in non-opening and opening filling wall and changing a given parameter, while keeping other parameters unchanged. This paper studies the influence on the Lateral Stiffness of Frame Structure, to provide Earthquake Fortifying Areas with reference data in the design process of filling wall.

Multi-Storey Timber and Mixed Timber–RC/Steel Construction in USA

Multi-storey timber-frame construction is used in North America for both residential and commercial structures. Timber is the predominant structural material used in residential construction throughout the USA. Reinforced concrete and steel assemblies mixed into timber-frame structures provide added performance for fire protection and earthquake resistance. This paper reviews the development of multi-storey timber-frame construction in the USA and the use of timber-frame mixed with concrete and steel elements.

Building Tall with Timber: A Paean to Wood Construction

It may seem strange at first to propose that timber be used for the structural system of mid-rise buildings. Steel and concrete have held that position so long that the question of wood as an alternative for large-scale multi-storey construction would strike many people as archaic and impractical, but until the modern age, this was the case. The following essay highlights some interesting examples in history, concluding with the 17 blimp hangers constructed in the USA during World War II when steel was in short supply. Each of these structures was a third of a kilometer in length and equivalent in height to a 17 storey building, containing a single, column-free room.

FIRE PROTECTION USING OFF-SITE APPLIED INTUMESCENT COATINGS.

Keywords BRITISH STEEL FIRES, PROTECTION, OFFSITE, COATINGS, APPLIED, INTUMESCENT, STRUCTURAL, STEELWORK, MULTI STOREY, BUILDINGS, TAIL, STRUCTURES, STEEL, TEMPERATURE, HEAT, COSTS, CONSTRUCTION, ECONOMICS, HANDLING, DAMAGE, REPAIRS... Show All

Field measured two-way slab deflections

Results of a survey of two-way slab deflections both during and after construction of a 28-storey office tower are presented. A comparison is made between measured deflections and deflections computed using a finite element program that includes the effects of cracking. Effects of construction loading and time-dependent deformations are included in the calculations. The measured and calculated deflections illustrate the high variability that can be expected in two-way slab deflections. Key words: concrete construction, deflection, finite elements, loads, multistorey construction, two-way slabs, variability.

An ‘open system’ a Danish approach

It is increasingly necessary for new building systems to comply with internationally established conventions as to performance, dimensions and compatibility. This article explains how such conventions have been adhered to in evolving a new Danish system for multi-storey construction developed by consulting engineers Lemming & Eriksson.

Building failures: floor support shoring in multi-storey construction

Recent collapses of multi-storey buildings under construction in America have highlighted the problem of shoring wet concrete floors until they are self-supporting and rigid enough to resist plastic deformation. The author offers practical guidance based on experience and a knowledge of available research findings.

Will large-panel construction hold its popularity?

CIB Commission W19 has done a great deal of work on the technical problems associated with the development of large-panel systems in multi-storey housing, a subject in which CIB Commissions W49 and W51 are also interested. Together with the new Steering Group S56 it is also organising a symposium on the use of spatial or boxed room units for multi-storey construction which is to be held in Budapest in May this year. Both these systems and the lift slab-system are discussed in this paper which has been produced by the authors as a forerunner to the conference.