Self-compacting concrete (SCC) is a modern high-performance concrete, which is characterised by excellent performance in flowing and filling ability which required a high amount of cement. Nowadays there are many alternative materials, which possible to be used as a replacement of cement to overcome the negative effect due to the usage of cement such as ground granulated blast furnace slag (GGBS) and metakaolin (MK). This study aimed at investigating the fresh and hardened properties of SCC produced by GGBS and MK as partial cement replacement. Cement was replaced with MK at a constant level of 10% while GGBS is substituted cement at various levels of 15%, 20%, 25% and 30% as a ternary blending powder. Results obtained indicates that the inclusion of MK reduced the workability, oppose finding for GGBS exhibited improvement in the workability. For the hardened properties at an early age, mix which contained MK showed improvement in the strength characteristics, whilst at later age the mix with a combination of MK and GGBS exhibited better performance. From this study, it can be concluded that the optimum replacement level of cement to produce good quality of SCC is 10% and 25% for MK and GGBS, respectively.

Textile-reinforced concrete (TRC) is a form of reinforced concrete, where conventional reinforcement is replaced with textiles or fibers. The high tenacity of the textile fibers results in flexible and durable concrete structures. The literature has been limited to TRC applications in retrofitting and nonstructural applications. Therefore, this article attempts to detangle the progressive research direction on the usage of TRC as a structural member. For this, (i) a bibliometric study using scientometrics analysis to visualize the keyword network, and (ii) qualitative discussions on identified research areas were performed. The literature was categorized into four main research areas, namely material properties of TRC, composite behavior of TRC, bond-slip relations, and TRC applications as structural elements. In addition, the advantages and disadvantages in the usage of TRC as a structural member are discussed in association with the identified research areas. Furthermore, the article proposes future directions to reinforce the research on the usage of TRC as a structural element.

The intermodular connection between modules plays a vital role in the overall performance of modular structures. The separation between a column and connection is possible due to the absence of links (welding or bolting) since limited space is available between modules. This study proposed a self-locking joint to be used in a modular steel structure, connecting columns with a connection without need of extra space between modules. The behavior of the proposed connection subjected to monotonic load was evaluated using a finite element approach using ABAQUS software. The influencing factors contributed to the behavior of the self-locking connection and columns observed using a parametric study. The parametric study was conducted by varying beam thickness, bolt pretension force and friction coefficient µ. Results indicate that the proposed connection can be classified as a semirigid connection according to Eurocode 3 and special moment frame (SMF) as recommended by AISC.

Numerous works investigating the use of rubber waste as aggregate in concrete have been well documented. Most of the works covered the enhancement method in improving the mechanical properties of rubberized concrete. However, limited works on permeation-durability related characteristics of rubberized concrete have been reported. In this study, further understanding on metakaolin blended concrete containing 10% treated crumb rubber with respect to its permeation-durability behaviour is discovered. The effectiveness of rubberized concrete with the two-stage approach where sodium hydroxide solution treated crumb rubber combined with 15% metakaolin was evaluated on workability, compressive strength, permeation, and durability properties at a different level of superplasticizer (0.25%, 0.50%, 0.75%, and 1.0%). The permeation tests included absorption and permeability whereas rapid chloride permeability and carbonation tests were for durability assessment. The results showed that the reduction in permeation properties and better durability resistance were achieved at a superplasticizer level of 0.75%. Thus, it can be concluded that the good workability of concrete mixture able to discontinued pore connectivity and resulted in high permeation and durability resistance of metakaolin blended-rubberized concrete.

Experimental study of five full scale masonry wall panels subjected to prescibed pre-compressive vertical loading and increasing in-plane lateral loading is discussed. All five walls were constructed using interlocking mortarless load bearing hollow concrete blocks. The behaviour of wall in term of deflections along the wall height, shear strength, mortarless joint behaviour and local and overall failures under increasing in-plane lateral loading and pre-compressive vertical loading are reported and analysed. Simple strut-and-tie models are also developed to estimate the ultimate in-plane lateral capacity of the panel walls tested. The results indicate that, as the pre-compressive load increases, the in-plane lateral load capacity of walls increases. All walls tested failed due to diagonal shear and/or moderate toe crushing depending on the level of the pre-compressive load. The proposed strut-and-tie models were able to give reasonable predictions of the walls tested.

In reference to the alumino-silicious binder materials, it is observed that almost all studies composed of binary and ternary geopolymer systems have focused on fly ash (FA) and ground granulated blast-furnace slag (GGBS) as primary source materials. Despite their technical benefits, this scenario is attributable to the high availability of the binder globally and its low cost. Various research had been done on the elimination of heat curing on the application of FA-based geopolymer composites. However, most studies have put a focus on Class-C FA, which has a high calcium content. As such, this research is exploring the enhancement of Class-F FA (low calcium content) and the potential of palm oil fuel ash (POFA) as the source of binder in FA-based geopolymer systems. POFA has similar characteristics to FA but POFA possesses slightly higher calcium content compared to Class-F FA. A systematic evaluation was carried out on an FA-based geopolymer mixture with the incorporation of GGBS. POFA was included as a secondary compound and for the tertiary compound at a range of 10%–30%. Meanwhile, 10% metakaolin (MK) was used as a tertiary compound in the FA/POFA geopolymer system. Alkaline activators of combination between sodium silicate and sodium hydroxide with a ratio of 2.5, 12 M sodium hydroxide and a liquid-to-binder ratio of 0.43 were used for the study. The geopolymerisation reactivity, setting time, flowability, and strength were the properties evaluated. Additionally, statistical analysis and sustainable assessment were done to highlight the environmental advantages. This approach offers a pathway to reduce reliance on Portland cement, contributing to environmentally friendly construction practices. Overall, the findings revealed that high FA content results in high early strength with the incorporation of GGBS. POFA demonstrates its viability for use in both FA/GGBS and FA/POFA geopolymer systems. Nonetheless, the usage of POFA should not exceed 20% when the FA content is high. FA-based geopolymer reduced carbon emissions around 68% compared to conventional cement. Ultimately, the strength achieved by the FA-based geopolymer system shows its potential as an alternative construction material for industry.