An investigation on effect of rebar on structural behaviour for wall-slab system
The government is taking the leading role to persuade the construction industry to engage a more systematic approach and methodology in construction by adapting the Industrialized Building Systems [IBS]. Wall-slab structural system is an IBS system which is suitable for use in residential building. Moment transfer of joint is an important aspect for proper structurally functioning of wall-slab system. Hence, the main aim of this study is to investigate the effect of reinforcement details in the wall on bending capacity for support stiffness in wall-slab system for residential project in Malaysia. A total of six wall specimens were tested. Three of this specimens consisted single layer of rebar while another three specimen consisted of double layer of rebar. The size of the wall-slab's specimens is 1000 mm in length [L], 1080 mm in width [W], 1000 mm in height [H] and 80 mm in thickness [T]. The average concrete strength Grade 30 N/mm2 and the average yield strength of R5 bar was 817 MPa. The bending capacity at failure for single layered of rebar in wall for specimen 1, 2 and 3 were found to be 3.59 kNm, 3.81 kNm and 3.15 kNm, respectively. The bending capacity at failure for double layered of rebar in wall for specimen 1, 2 and 3 were 5.50 kNm, 6.31 kNm and 7.00 kNm, respectively. The difference in stiffness of double layered reinforced concrete wall based on load-deflection curve 116.2 % to 289.9 % higher than single layered reinforced concrete wall. While based on the experimental results, specimens with double layered rebar in wall is found with higher bending capacity by 56.3 % to 98.9 % compared to single layered of rebar in wall. Experimental data on bending capacity provides important input in the process of structure analysis. Others than that, the outcome obtained from the study can serve as an useful guideline in the design of an efficient joint in wall-slab structural system.
Issues and challenges in the implementation of Industrialised Building Systems in Malaysia
The Industrialized Building Systems (IBS) Roadmap 2003-2010 published by the Construction Industry Development Board (CIDB) outlines several well-thought strategies and aggressive steps to promote the use of IBS in Malaysia. The government is taking the leading role to persuade the construction industry to engage a more systematic approach and methodology in construction. It is a strategic change in the construction industry and the effort started in 1998. Besides the aim to gradually reduce the dependency on foreign labour and saves the country from losing out foreign exchange, IBS provides the opportunity for the players in the construction industry to develop a new image of the construction industry to be at par with other manufacturing industries such as car and electronic industries. With the present conventional methods of construction, the industry is always associated with many unprofessional practices. The adoption of IBS promises to elevate every level of the industry to a new height and image of professionalism. By adopting IBS, efficient, clean, safe, professionally managed and handled by professionals and workers with relevant skills, proper coordination and management, precision, innovative and quality will be appeared as new attributes to be associated with the construction industry. The industry players are expected to venture internationally and one of the pre-requisite to compete globally is to offer quality, efficient and professional services and again IBS can be an excellent option. Although some of IBS have been introduced in Malaysia as early as in 1960â€™s, the industry as a whole seems quite reluctant to exploit the use of IBS. A recent survey carried out on the use of IBS in Malaysia reveals some of the issues and challenges, which require attention from different parties.
Cyclic Testing of Simple Connections Including Effects of Slab
The problems with welded moment connections in the Northridge earthquake of 1994 gave researchers incentive to examine the actual contribution of the simple, or shear, connections to the lateral resistance of welded steel moment-frame buildings. With the composite action of the floor slab, these connections may have more lateral resistance than traditionally assumed; thus, they may be used in the repair or retrofit of damaged welded steel moment-frame buildings or used more actively in new construction. To evaluate these possibilities, and to establish the strength, stiffness, and ductility of these connections under cyclic loading, two series of eight full-scale, cyclic tests on shear connections with floor slabs were planned. The first test series has demonstrated the cyclic behavior of the simple connections and has shown that these “pinned” connections have significant moment capacities, both on their own and with the contribution of the floor slab. This paper summarizes the results of the first eight...