Clamping and interlocking effects on IBS block house system in comparison with conventional house system

Industrialised Building System (IBS) is a unique construction technique that has been implemented in many construction fields all around the world. However, its implementation in Malaysia is still slow and not effective. Through the research on IBS, some elements are found to be important and need to be improved in order to produce better quality components. One of the important elements is the design and innovation of IBS components by applying new interlocking configuration between blocks and by using a clamping bolted connection to the system. The main objective of this research is to determine the structural behavior of IBS block works sub-system under push over cyclic loading in comparison with conventional sub-system and to verify that the IBS interlocking geometry sub-system perform better than other sub-systems via laboratory tests. In this research, a block work assembly to form building sub-frame that integrated by two beams, two columns and infill system were built and tested to failure. Two types of IBS block work sub-systems with original geometry and interlocking geometry with scaled of 1:5 were tested with Push Over Cyclic Load Test. In comparison, a control model of Conventional Sub-System was also tested and analysed using the same methods. The results showed that the IBS geometry model with interlocking configuration performed better in terms of stiffness, ductility and flexibility of the models. The IBS original geometry model is ductile but lack structural stiffness while the conventional model is stiff but not ductile

Seismic performance of scaled IBS block column for static nonlinear monotonic pushover experimental analysis

his paper presents the seismic performance of the down scaled 1:5 model IBS block column with non-linear static analysis. The aim of this research is to access the ultimate capacity and structural behaviour of the IBS block column. This paper demonstrates the theoretical prediction of the full-scale prototype strength based on scaling factors at non-linear state. Besides, this research investigates the ultimate shear capacity, stiffness, bolt strength, inter-storey drift and block separation for prediction of seismic performance levels. Concrete material properties, mix specification and steel reinforcement detailing for scaled model are tabulated in this paper. The methodology of this research begins with full scale prototype design, scaling to the small model and followed by the scaled model fabrication. Theoretical lateral load prediction associated with scaling factors are also performed. The experiment test was carried out on the assembled scaled 1:5 IBS block column with proper displacement measuring equipment on test rig and graphical capture tools. The data of roof top displacement with base shear capacity, inter-storey drift and gap separations were tabulated for discussions. The tested ultimate roof top displacement was 128 mm with 3.1 kN base shear. The calculated elastic stiffness of the IBS block column was 0.137 kN/mm, followed by yielding stiffness of 0.033 kN/mm and 0.014 kN/mm plastic stiffness. The significant inter-storey drift was due to cracking and crushing of column blocks edges. The measured maximum separation gap was 24.4 mm located at 340 mm height due to the rocking of the column. Based on seismic performance levels indicator from FEMA 273 & 356, the column was in the state of immediate occupancy with 21 mm roof top displacement and 1.7 kN base shear. The life safety is limited at 65.27 mm roof top displacement with 2.4 kN of base shear. All scaled down data was then reverted to full scale prototype capacity according with the respective scaling factors. It concluded that the IBS blockwork column is capable of resisting the seismic event without falling of the blocks that endanger the occupant life at the maximum credible earthquakes of 1.3 g horizontal spectral acceleration equivalent to X+ Mercalli’s scale

Analysis of reinforced concrete shear walls with single band of octagonal openings

The applications of cast-in-situ reinforced concrete shear walls for tall buildings are prevalent in many countries. Shear walls with openings are called coupled shear walls which act as cantilevered walls joined by coupling beams. Openings for windows and doors affect the behaviour of the structure and cause to decrease the strength of shear wall. Some methods were suggested in the past to increase the strength of shear wall but they are not easy to apply and need labour attentiveness. This study proposes adding haunches to the corners of rectangular openings as a simple method to increase the strength of coupled shear wall structures. Analytical analysis employing Total Moment Concept and Continuous Connection Method (CCM) and Nonlinear Finite Element Analysis (NLFEA) were carried out on symmetrical shear walls with single band of octagonal openings. The results are compared with outputs of previous study on shear wall with rectangular openings. The analysis results demonstrated that it is confidently worth to use the octagonal openings due to very small percentage increase in the total weight of the structure compared with the amount increase in ultimate load of the shear walls

Proposing of new building scheme and composite towards global warming mitigation for Malaysia

The building sector has been regarded as a potential sector where there is large capacity to reduce the climate change effect. This study has proposed solutions to mitigate environmental impacts and achieve low CO2 emission from residential sector. Therefore, full life cycle assessment (LCA) has been run to assess the CO2 emission and its effect on the atmosphere and climate change. Based on the result, timber scheme is the best choice due to releasing less CO2 emissions to the atmosphere. However, house builders in Malaysia have almost completely neglected timber as a building material, with timber use as building components reduced to 5%. In this study, LCA Software was used to assess CO2 emissions from different wall construction. The alternative building scheme has been made by reinforce steel stud, wooden beam and timber wall (S8) to improve the scheme deficiency while releasing less CO2 emissions compared to other schemes. Therefore, S8 has a decreased CO2 effect by 85% less than precast concrete frame and 90% less than brick over their lifetime. (S8) increased the load bearing compared to conventional timber beam. Thus, new scheme S8 could be replaced by current scheme and promote more adjustable scheme for Malaysian housing

A study on rotational behaviour of a new industrialised building system connection

The performance of an Industrialised Building System (IBS) consists of prefabricated reinforced concrete components, is greatly affected by the behaviour of the connection between beam and columns. The structural characteristics parameters of a beam-to-column connection like rotational stiffness, strength and ductility can be explained by load-rotation relationship of a full scale H-subframe under gravitational load. Furthermore, the connection’s degree of rigidity directly influences the behaviour of the whole frame. In this research, rotational behaviour of a patented innovative beam-to-column connection with unique benefits like easy installation, no wet work, no welding work at assembly site, using a hybrid behaviour of steel and concrete, easy replacement ability, and compatibility with architecture was investigated. The proposed IBS beam-to-column connection includes precast concrete components with embedded steel end connectors. Two full-scale H-subframes constructed with a new IBS and conventional cast in-situ reinforced concrete system beam-to-column connections were tested under incremental static loading. In this paper, load-rotation relationship and ratio of the rigidity of IBS beam-to-column connection are studied and compared with conventional monolithic reinforced concrete connection. It is concluded that this new IBS beam-to-column connection benefits from more rotational ductility than the conventional reinforced concrete connection. Furthermore, the semi-rigid IBS connection rigidity ratio is about 44% of a full rigid connection

The role and importance of standards in cost optimization and increased productivity and quality in constructing health centers

Standardization of building process in medical sectors has provided the ground for specialization levels, ensuring the future buildings will have better quality. The life span of Health Centers in Iran is only one quarter of same building in other countries, which leads to extra cost for both structure and non-structure (hospital facilities & equipment) and So far, there are no approved regulations to make health care spaces. The aims of this research are reducing the cost of building, facilities and equipment and increasing productivity implies the provision of standard spaces in which the facilities are optimized by proposing Quality management model. This research has discussed the deficiency of building regulations in healthcare sector. The interviews accomplished for collecting data about defects in construction of health center and hospital. The primarily result shows that the budget estimates are not correct, design is done poorly, and studies are not accurate, so long construction time can cause a depreciation of structures. Due to the increasing need of society for healthcare spaces and their high level of construction, standard regulations should be regarded in cost optimization and increasing productivity and quality in order to maintain national assets for future generations. Finally, based on requirement a model is suggested for improving current practice definition and revision of existing laws for medical spaces. The model has been divided into ten categories namely: planning, organize, communicate, substructure, education, leading the process, control, predict variation, accessory measures and finally documentation