popular due its fast erection and they have quite good quality because all panels are produced in factory. This wall panels act as the bearing element of the building but the main issue of this wallpanel is its connections. The wall panels act as a single unit system to avoid failure. So the purpose of the thesis is to study how to choose the right capacity of the connection devices and to research vertical joint of precastconcretewallpanel. The thesis is concentrated on bolted connection for vertical joints of precastconcretewallpanel. For this the behaviour of proposed bolted connection such as working of connection, deformation of wallpanel, stresses in the connection elements, mechanical properties of connection elements are analyzed for assumed loads. The proposed bolted connection at vertical joint is modeled between two wallpanel using Ansys spaceclaim software and is imported to ANSYS 19.2 software. The finite element analysis of proposed bolted connection using ANSYS 19.2 is discussed.
Precastconcretewallpanel which is currently being used as cladding or curtain walls, does not take any advantage of the panel’s structural capabilities. Non-load bearing precastconcrete cladding is noted for its diversity of expression as well as its desirable thermal, acoustic and fire resistant properties. However, it is commonly overlooked that precastconcrete elements normally used as cladding applications, such as sandwich wall panels, solid panels and spandrel panels, possess considerable inherent structural capacity. The mandatory amount of reinforcement required to handle and erect a precast component is often more than necessary for carrying imposed loads in case of low or medium-rise structures. Thus, with relatively few modifications, many cladding panels can function as load bearing elements. As with all precastconcrete applications, further economies can be realized if the panels are repetitive. By making panels as large as possible, numerous economies are realized: the number of panels is reduced and fewer joints (waterproofing requirements), lower erection cost, and fewer connections are required.
After study of different housing materials it is observed that concrete is versatile material and its ingredients are easily available in India and all over the world, for the project work major material is consider as wire mesh concrete, which is used in prefabricated concrete product as cement concrete door and windows frames, prefabricated concrete ventilators, wall panels which is majority used in khandesh are. For this work precastconcrete product factories in khandesh area are observed and from that observation one technique which is use in precastconcrete compound wall panels is selected as the cost efficient technique for this project work, it is made up of wire mesh concrete techniques, wire mesh of 2-3 mm diameter is used as reinforcement and the thickness of the panels of 5 to 10 cm depending upon its use in different situations, generally 5cm thick wall panels are used in precast compound walls ,use of wire mesh is reduce the cost of normal steel used concrete works. Following figures shows the casting and fixing of precastconcretewallpanel pro ducts which are easily available in the khandesh area.
There also previous research that studied about the composite behaviour of insulated concrete sandwich wall panels (ICSWP) subjected to wind pressure and suction [30]. The specimens was castes full-scaled with different type of insulation and number of glass-fiber-reinforced polymer (GFRP) shear grid. The results show that bonds based on insulation surface roughness were effective under both positive and negative loading test. The calculation of ICWSP’s design strength used the composite behaviour based on surface roughness due to those particular reason.
Tarek K. Hassan and Sami H. Rizkalla (2010), on the studies of “Analysis and design guidelines of precast, prestressed concrete, composite load-bearing sandwich wall panels reinforced with CFRP grid”, investigated three different precastconcrete sandwich wall panels, reinforced with carbon-fiber-reinforced-polymer shear grid and constructed using two different types of foam, expanded polystyrene (EPS) and extruded polystyrene (XPS), were selected from the literature to validate the proposed approach. The results of the analysis indicated that the proposed approach is consistent with the actual behavior of the panels because the predicted strains compared well with the measured values at all load levels for the different panels. Besides that, the approach is beneficial to determine the degree of the composite interaction at different load levels for different panels at any given curvature. A simplified design chart is provided to calculate the nominal moment capacity of EPS or XPS wall panels as a function of the maximum shear force developed at the interface. A simplified design chart is proposed to calculate the nominal moment capacity of EPS and XPS foam-core panels at different degrees of composite interaction. The chart is valid only for the panel configuration, geometry, materials, and reinforcement used in the current study. However, it can easily be produced for different panels. The chart demonstrates the effect of composite interaction on the induced curvature.[19]
This study is aimed to provide information about the structural behaviour of PLFP with shear connectors. It is able to get a clear and deeper insight on the structural behaviour and failure mechanisms of the PLFP with single and double shear truss connectors under axial and push off loading. The results from this study are very important to assist the design of the PLFP to be used as a precastwall system especially the ultimate load carrying capacity and failure mechanism. An empirical equation is proposed in this study which is able to predict the ultimate load carrying capacity of PLFP under axial loading. The equation can be used to predict the maximum load of sandwich in non-linear behaviour after the service load.
A Hollow core slab is a precast, prestressed concrete member consisting of continuous voids extending the full length of the slab. Precast slabs are extensively used in prefabricated buildings as floor or roof deck system and also have the applications in spandrel members, wall panels and bridge deck units. Structurally, a hollow core slab provides the efficiency of a prestressed member. The natural diaphragm action available in the cast - in-situ slabs for resisting lateral loads can also be emulated with proper connection details among adjacent components. As far as the slab is concerned, the flexural properties like bending
The sandwich panel technology, which has evolved gradually over the past forty years, has enabled the foregoing of these issues because of the ability to be delivered on-site directly and arrive ready for erection. Recently, the sandwich panels design concept has leaped forward by introducing fiber reinforced polymer, or FRP, shear reinforcement grids allowing for benefits that make the use of these panels even more desirable than ever before as they have a relatively low thermal conductivity compared to that of steel. Carbon FRP shear grid connectors have been successfully used by Altus Group to produce precast prestressed concrete sandwich panels that are both structurally and thermally efficient (Gleich, 2007). Glass FRP grid produced in Korea also has the potential for achieving similarly desirable panels at a lower cost, as the thermal conductivity is even lower than that of carbon fibers and the cost of glass FRP tends to be significantly lower. However, optimal design practices for using glass grid shear connectors are still unknown.
Precastconcrete load-bearing wall panels have become a popular choice for low-, medium-, and high-rise construction in North America. An integral part of this structural system is the horizontal connections between wall panels, since it directly affects the strength and stability of the structure. A very common connection method is the grouted dowel connection, where a reinforcing bar protruding from the lower wallpanel is grouted into a corrugated steel duct cast into the upper wallpanel. Despite the common use of this connection in practice, there are no pertinent specific code requirements that guide this use, and related research is sparse. Furthermore, this construction proceeds throughout cold weather conditions, with the connection area typically heated for one day then exposed to subfreezing temperatures, before the grout is fully cured. The effects of exposure to early-age subfreezing temperatures on the bond behaviour of this connection are still not well understood. Thus, the focus of this research was to fill this knowledge gap by exploring the bond behaviour of this connection for use in precastwallpanel construction, and the effects of exposure to early-age subfreezing temperatures on the connection’s bond strength.
From the study of precastconcrete bearing wallpanel applicable for 2-story house under reverse cyclic load, the conclusion can be drawn. The specimens are 3/4 scales and have the same reinforcement details as the real wall which is gravity load design. The connection detail is dowel bar welded to steel plate embedded in wallpanel, which represent 2-story house load bearing wall in Thailand. The specimen was tested and compared with the in-situ reinforced concretewallpanel specimen. Tested result shown that, the maximum load is the same, 38.8 kN and 39.4 kN for precast and reinforced concretewall specimen, respectively. The crack for precast specimen is concentrated around concrete cover steel plate connection while both side of flexural and shear crack in wallpanel 500 mm above the footing occur in reinforcement specimen. Although precast connection is gravity load design, it can resist lateral load almost the same as reinforced concrete specimen. FEM analysis also shows according results and extracts the force flow in the wallpanel. It can be implied that the tested connection of precastconcrete bearing wall can be applied for low to moderate seismic region. For high seismic region, the connection has to be modified and more study for safely used.
Precast prestressed concrete insulated sandwich wall panels have been used over the past 50 years. One of the earliest reported uses of concrete sandwich wall panels for building construction was in 1906. With the advancement of the materials and methods of construction over decades, the production of these panels has been improved and become more efficient. Typical sandwich wallpanel consist two layers of concrete separated by foam core. The two concrete wythes are typically connected by different type of shear connectors. The materials for production have evolved over the years and higher quality control is achieved in construction of these panels as they are casted in a factory (PCI Committee on Precast Sandwich Wall Panels, 2011). Shear transfer mechanisms have evolved from solid concrete zones to steel truss mechanism. A major criterion in the recent advancements of precastconcrete sandwich panel technology has led the building owners to attain Leadership in Energy & Environmental Design (LEED) certification. LEED maintains requirements and guidelines for thermal performance of building envelopes, focusing the precast industry’s attention toward a more thermally efficient panel system.
Tarek et al.[15], investigated three different precastconcrete sandwich wall panels, reinforced with carbon- fiber-reinforced-polymer shear grid and constructed using two different types of foam; namely, expanded polystyrene (EPS) and extruded polystyrene (XPS). The results of the analysis indicated that the proposed approach is consistent with the actual behavior of the panels because the predicted strains compared well with the measured values at all load levels for the different panels. Besides that, the approach is beneficial to determine the degree of the composite interaction at different load levels for different panels at any given curvature. A simplified design chart is provided to calculate the nominal moment capacity of EPS or XPS wall panels as a function of the maximum shear force developed at the interface. A simplified design chart is proposed to calculate the nominal moment capacity of EPS and XPS foam-core panels at different degrees of composite interaction. The chart is valid only for the panel configuration, geometry, materials, and reinforcement used in the current study. However, it can easily be produced for different panels. The chart demonstrates the effect of composite interaction on the induced curvature.
ABSTRACT:-This paper present of an experimental study on the effect of using industrial waste Polystyrene as a potential aggregate in light weight precastconcretepanel. Also in place of natural sand, crush sand stone were used. The effect of Polystyrene aggregate on several properties of concrete were investigated. For this purpose, five series of concrete sample were prepared. The polystyrene aggregate was used as a replacement of natural aggregate, at the level of 40%, 50%, 60%, by volume and crush sand stone was also replaced by polystyrene at the level of 10%,20% by volume. The 7-d compressive strength of polystyrene concrete ranges from 3.91Mpa to 6.18 Mpa which satisfies the strength requirement of light weight precastconcretepanel. Light weight precastconcretepanel made using Polystyrene are effectively used in partition walls, compound wall,parapet wall, w/c unit, road divider and other non- load bearing elements of the buildings as they provide required compressive strength. These elements shows good thermal insulations and durability. Light weight concrete can be made in any size and shape as per the requirement. KEYWORDS:-Light weight, Economy, waste minimize, Easy Handling and Installation, Eco-friendly, High Durability.
Xella AAC Texas, Inc., located in San Antonio and San Juan, Texas, distributes lightweight steel- reinforced, precastwallpanel that delivers a fast and efficient building material for solid wall construction. These vertical and horizontal wall panels, which can be installed as exterior non-load bearing walls in commercial applications or as firewalls, are intended to respond to today’s design challenges for increased energy efficiency, fire safety, and sound transmission, as well as increased concern over construction safety and resultant libilities. A consequence, exciting new design applications using Xella Texas’s AAC, are almost unlimited. These building components are made of autoclaved aerated concrete (AAC), a result of German research and technological advanced. Hebel Wall Panels are designed to increase the speed of commercial, industrial and institutional construction and are a
The vertical joints are designed to transfer shear forces under lateral loads. The joint faces are indented to provide shear keys for shear transfer with increasing lateral loads. Beyond cracking of concrete, a strut-and-tie action is expected to develop. Overlapping reinforcing loops are provided along with shear keys to take up the horizontal component of the inclined compressive strut.
Sustainability in construction industry has become an issue when designing a new building [1] and the conventional on-site construction methods have long been criticised for imposing rigorous human health and safety risk, as well as causing significant environmental destruction [2]. Meanwhile, PCSP can be perceived as an alternative approaches in creating and maintaining the sustainable built environment. Finsen & Georgia (2011) [1] said that this wall system can maximise benefits from integrated strategies, which focus on all of the building’s materials and systems, as well as the way they interact.
17 The author uses a flat solid panel 30 feet wide by 8 feet high and only 5 inches thick. Appropriate material properties were applied to the panel while steel reinforcement was neglected. Self weight was applied to the structure as well as a lateral wind load of 10 psf. The 3D solid model was divided into 240 eight noded rectangular elements. The stresses, strains, and deflections associated with the loading were then analyzed. The author concludes from experience and experimental results that the predicted values follow expected behaviors. Thus the analysis is successful. The author suggests that a design engineer can use the model to analyze the panel and decide on locations and amounts of reinforcement necessary. The author also states that the model is easily modified to examine different parameters for design such as load cases and support locations by changing the input for the model. The author then gives a general analysis procedure. This procedure is a three step process. The first step is data input, the second is a solution step, while the last is the post solution step. The data input step includes setting the geometry of the panel, specifying loads, and defining the elements. The solution step involves the time and cost associated with solving the problem. Finally, the post solution step involves interpreting the data by creating graphs, tables, and plots of the solutions for analysis by the designer. Lastly, the author concludes that finite element modeling is practical for predicting precastconcretepanel behavior and that these models can be used in parametric studies.
compressive strength than the Auto cleaved Aerated Concrete [AAC] its flexural toughness was more than 100 times more than AAC due to the role of fibers in bridging the micro and macro cracks. With very low thermal conductivity values, FRAC can be a used as a sustainable construction material for residential applications [3].The addition various air entraining agents causes the concrete to rise like cake but it reduces the strength of concrete due to the formation of air voids. Oleic acid results in maximum reduction of density as compared to other air entraining agents like hydrogen peroxide and olive oil. The dry density and compressive strength of the mix reduces slowly when the admixture proportion is increased from 0% to 0.5% and then to 1%.The dry density and compressive strength of the mix reduces gradually when the admixture proportion is increased from 1% to 1.5%.[10]Precastconcrete sandwich panels are commonly used to construct the outer shells of numerous typical buildings such as residential, commercial and warehouses; and as they are vertically spanned between foundation and floors or roofs that mostly resist the axial/compression loads.[12] The dosage of aluminum powder required to achieve a desired density reduces with an increase in its fineness. Al powder with fineness C50 provides higher strength to density ratio and lower water absorption [5]. The externally bonded textiles layers significantly improved the mechanical properties of lightweight low-strength aerated concrete core. Dynamic flexural strength was greater than the static flexural strength by as much as 4 times. For specimens with larger cross- sections, unreinforced-autoclaved AAC core had a 15% higher apparent flexural capacity. With 0.5% volume of polypropylene fibers in the core, the flexural toughness however increased by 25%[11].Thermal conductivity of fiber substituted autoclaved aerated concrete changes linearly with thermal conductivity of the substituted fibers and basalt fiber reinforced autoclaved aerated concrete gives the highest thermal conductivity. But, it has been seen that the best compression and flexural strength was given by the carbon fiber reinforced samples. Fibers create a physical bond in the materials and remain independent greatly affected the result. Polypropylene and glass fibers increased the compressive and flexural strength of the samples but on the other hand, it also increased their thermal conductivity [6].
Concrete is a heterogeneous mixture of sand, gravel, cement and water, plus air, salts, fine inert materials and other additives or admixtures which modify the characteristics of concrete (PCI, 1991). Historically, concrete is a widely used construction material in civil engineering projects throughout the world. Other than building construction, concrete has also been used in structure such as shelter, retaining wall, barrier, offshore structures, and nuclear reactor containment. The reasons for using concrete in construction material are it has excellent resistance to water, it can be formed into a variety of shapes and sizes and it is usually the cheapest and most readily available material for the job (Mehta and Monteiro, 2006). Concrete strength depends upon many factors such as materials used, placement, curing, mix design and control during the mixing process.
popular in Malaysia. Construction field in Malaysia has achieved another new milestone when the pioneering project of Pekeliling Flat in Kuala Lumpur has been successfully built within 27 months which utilized the panel pre- cast concretewall and plank slabs in the project [3].Nowadays, there are many local IBS manufacturers and the number is rapidly escalating. Most of the IBS systems used in Malaysia are large panel systems, steel frame, precast frame and formwork system. All these systems have been largely used for private residential projects in Malaysia which include projects in Shah Alam, WangsaMaju and Pandan, Dua Residency, KL, Taman Mount Austin and TongkangPecah, Johor [3].In the 21st century, IBS is not new to the construction industry. This method can effectively save costs and improve the construction quality by reducing labor intensity and construction standardization. Besides, it minimizes waste, reduces site material, yields cleaner and neater environment, provides higher quality control, and cuts the total construction costs. Examples of successful implementation of IBS in the world include Sesikui Home (Japan), Living Solution (United Kingdom), Open House (Sweden) and Wenswonen (Netherlands) [4]. This study focuses on precastconcrete system in IBS method. Basically the study emphasizes the building maintenance for precastconcrete system. Precastconcrete system should be approached focusing on the building maintenance concept. Precastconcrete system with maintenance concept are related to the planning, organizing, monitoring, design, construction and manufacturing which can be concluded as building maintenance factors in design, manufacturing and construction stage for precast