CHIRI Capability

SUSTAINABLE CONSTRUCTION MATERIALS

Use of Industrial Wastes for High-Performance Concrete    

Our team received an industrial research fund from Novakey Sdn Bhd in 2017, studying the strength and durability behavior of artificial armor stone using high-performance concrete incorporating industrial waste and marine sand for the breakwater. The use of locally available materials in concrete production, such as marine sand and seawater, reduces the need for material transportation and thus saves cost and time. Concrete production costs can be reduced even further by utilizing industrial wastes such as silicomanganese (SiMn) slag, fly ash (FA), and silica fume (SF) as alternative materials. The incorporation of these materials not only conserves the conventional resources but also provides a more effective waste management plan. In the hostile marine environment, concrete is susceptible to several types of deterioration, which can be exacerbated by wetting-drying action (WDA). The study monitors the synergy of two deterioration types, particularly between sulfate attack and cyclic loading. Against this backdrop, this research aims to develop a concrete mix design that incorporates marine sand, seawater, SiMn slag, FA, and SF for application in marine environments subjected to WDA. The publications related to this project are in the following.

SUSTAINABLE DESIGN AND CONSTRUCTION  

Green Technology and Green Infrastructure 

Worldwide development in sustainable management and green initiatives in infrastructure projects are encouraging and heightened the demand for extensive research in various elements of sustainable infrastructure development. Growing environmental and socioeconomic concerns due to rapid urbanization, population growth, and climate change impacts have motivated decision-makers to incorporate sustainable best practices for transportation infrastructure development and management. Infrastructure development includes roads, rails, water utility services, airports, ports, and telecommunications. Among all, road and highway infrastructure are primarily essential to meet the transportation and mobility demand, with a growing population and increased urbanization which links towns and cities. Road infrastructure emits one the highest amount of greenhouse gasses (GHG) among all, throughout its project life cycle, from raw materials production, construction, operation, maintenance, and rehabilitation. The traditional techniques (earthworks, pavement, plant, and equipment, etc.) used in the development of road infrastructure projects consume a large amount of energy and uses non-renewable resources. A green highway takes high consideration on the approach of the environment to the transportation system development, the ecosystem, urban growth, public health, and also to surrounding communities. Malaysia joined the global effort in developing and implementing sustainable highway initiatives in optimizing the use of natural resources and reducing carbon emissions while expanding the nation’s road network to meet the user’s demand. Road maintenance works consume a large portion of materials and energy use in the long term for any given facility, considering the design life of more than 20 years. Therefore, the need to develop a comprehensive green rating framework for road infrastructure is extremely vital for the sustainable development of the nation. The ongoing study is to develop an enhanced green rating framework for a sustainable road infrastructure’s operation and maintenance works.

Treatment of Sewage Sludge using Natural-based Solution

The handling and treatment of sewage sludge from sewage treatment facilities and onsite sanitation systems is an environmental issue in Malaysia due to population growth. Improper sludge management poses a risk of public nuisance and health hazards. Besides, the cost of sludge management and disposal is up to 50% of the total operating costs of the sewage treatment industry. In order to meet the National Water Service Commission (SPAN)’s requirement of sludge dewatering, natural-based solutions such as sludge treatment reed beds (STRBs) are a promising alternative for sludge management. Such a system, which is also known as sludge treatment wetlands, dewaters the sludge through drainage and evapotranspiration under low-pressure conditions. The STRBs require minimum capital cost, electricity, and skills in operation and maintenance, while the dewatering capacity is comparable to those of conventional treatments. There have been extensive studies of the dewatering efficiency in STRB. Nonetheless, the lack of understanding of the effects of operational and design parameters on treatment efficiencies limits the use of STRBs in practice, where well-controlled operating regimes are necessary, not only to improve system lifespan but also to improve treatment performance. Accordingly, it is essential to understand the formation of sludge deposits and their dewatering dynamics to gain more insights into the optimum operating regime in the STRBs. The gap of knowledge in the dewatering capacity of STRBs can also be bridged between the theory and practice using a simulation study. A mechanistic model provides a platform to simulate the dewatering dynamic under a variety of scenarios and facilitates the investigation of mechanisms in the system. An ongoing research project, which is funded under the Fundamental Research Grant Scheme (FRGS) under the Ministry of Higher Education, focuses on the development of a robust simulation for the dewatering dynamics of sewage sludge in STRBs through simultaneous integration and modifications of moving boundary problems, filtration theory, and plastic limit of sludge deposit.

Steel-concrete composite structural components 

Steel-concrete composite structural components are widely used in engineering due to their small cross-section, low material consumption, and anticipated structural capacity. Composite slabs, which invariably comprise of profiled steel sheeting attached to concrete topping, are widely adopted in steel-framed high-rise building constructions. The profiled steel decking serves different functions in two different stages: to act as a permanent formwork that supports fresh concrete during the concrete casting stage and being a tensile reinforcement for the flooring system after concrete hardened in the service stage. Despite the numerous advantages of a composite slab, the performance of the slab is limited by its longitudinal shear-bond resistance between the profiled steel deck and concrete. The existing national standard, Eurocode 4, provides guidelines on determining the longitudinal shear strength of composite slab which requires extensive laboratory testing. Hence, it is necessary to develop less experiment-intensive design guidelines on the determination of the shear strength of the composite slab.

Durability of sedimentary rock 

Shale, a clastic sedimentary rock, is well-known as a problematic sedimentary rock in Sarawak. Stability problems in excavation/slope cuttings where shales are present are common and may lead to damage to infrastructure or other hazards. There is very little knowledge and understanding of the properties of shales in Sarawak, which leads to the uneconomical and unsustainable design of geotechnical works. This is ongoing research funded by the Ministry of Education to characterize the durability of shale against weathering. This research will provide a fundamental understanding of the geochemistry, mineralogy, texture, etc., of shale and their impact on the durability of shales against short-term weathering. This is a necessary step to develop stabilization methods of cutting/excavation in shales in the future.

Slope failures in sedimentary formation along Pan Borneo Highway

Local constraints identification and local specification review and improvement

CHIRI is committed to providing services to review and improve the current codes of practice and to assess the suitability and adaptability of new technology used locally in Sarawak. There are three ongoing projects engaging with Jabatan Kerja Raya. These include an evaluation of the existing methods for the design and construction of gabion walls, reviewing the technical guidelines and condition of surface channels of slope, and understanding of local constraints and acceptance level of IBS implementation for steel modular construction.

Steel modular construction

If you are interested in knowing more about CHIRI and the previous and current research projects, please contact Ir. Dr. Vera Loo Hui. (vera.loo@curtin.edu.my)