Publications

Rectangular Stress-block Parameters for Fly-ash and Slag Based Geopolymer Concrete

Synergistic effect of rice husk ash and ceramic powder on mechanical properties of ultra-high-performance concrete

This research examines the synergistic impacts of incorporating rice husk ash (RHA) and ceramic powder (CP) in ultra-high-performance concrete (UHPC). Four alternatives of UHPCs with different contents of RHA and CP were investigated. Specifically, the first two batches substituted silica fume (SF) with RHA at levels of 5 %, 10 %, and 15 %, whereas 10 %, 15 %, and 20 % RHA was used to replace cement in the third batch. The last batch, on the other hand, was designed to examine the synergistic effect of a fixed 5 % RHA and CP replacement proportions of 10 %, 15 %, and 20 %. Mechanical properties (i.e. compressive/flexural resistance and damping ratio), economic efficiency, and environmental impacts of the newly designed mixtures were determined. Compared to the reference mix, all mixtures experienced declined workability. While using RHA to replace SF exhibited either comparable or enhanced compressive and bending capacities, mixes with cement substitution had lower compressive strengths but higher flexural strengths. Regardless of substituting cement or SF, incorporating RHA consistently augmented the damping performance of the UHPC blends. The inclusion of both RHA and CP resulted in up to 17.2 % higher compressive strength, 47.9–59.1 % higher flexural strength, and 68 % higher damping ratio compared to the control mix, highlighting their favourable synergistic effects for developing high-performance and eco-friendly UHPC mixtures. The developed mixtures also demonstrated improvements of up to 40 % in cost-efficiency and reductions of up to 10.1 % in embodied carbon emissions (38 % carbon index).

Experimental and numerical study of the performance of geopolymer concrete columns reinforced with BFRP bars subjected to lateral impact loading

Seismic performances of CFRP strengthened rubberized concrete columns: Bidirectional shaking table test

Blast behaviour of precast segmental vs monolithic concrete beams prestressed with unbonded tendons: A numerical investigation

Impact Response of Prestressed Prefabricated Segmental and Monolithic Basalt-FRP-Reinforced Geopolymer Concrete Beams

The use of low-emission geopolymer concrete (GPC) and noncorrodible basalt-fiber-reinforced polymer (BFRP) bars is an effective strategy in the bid for net zero emissions and making sustainable and durable structures. To date, however, there have been no studies on the impact response of prefabricated/precast segmental concrete beams (PSCBs) constructed using GPC and BFRP bars. This experimental study, therefore, was intended to partially fill this knowledge gap. The key objectives were to investigate the impact behavior of the segmental versus traditional monolithic beams, the effect of impact location, and the performance of GPC versus ordinary Portland cement (OPC) concrete beams. The test results showed that, with the energy absorption capability derived from the opening and sliding of joints, the PSCB experienced less damage than its monolithic counterpart under similar impact conditions. The joints, however, reduced the global stiffness of the PSCB, resulting in the PSCB having a higher displacement, lower impact and reaction forces, but a longer impact force duration and greater impulse, compared to the corresponding monolithic beam. Under the impact loads, the PSCB had a higher tendon force but smaller reinforcement strain than the monolithic beam. Impacting at the joints mobilized the energy absorption capability more effectively, resulting in a reduction in impact-induced damage. The impact performance of both the monolithic and segmental GPC beams was quite similar to that of their OPC counterparts. Thus, GPC can be adopted as a sustainable alternative to OPC in the construction of concrete structures against impact loads. In this study, a three-dimensional finite-element model was also developed in order to obtain a better understanding of the impact behavior of segmental and monolithic beams.

Effect of fibre reinforcements on shear capacity of geopolymer concrete beams subjected to impact load

MDI Based Flexible Foam: A Status Report on World Developments

Compressive behaviour of locally corroded steel tubular members under eccentric loads

Modelling the behaviour of polymer coated reinforced concrete panels subjected to blast loads

Mechanical and microstructural properties of fly ash-based engineered geopolymer mortar incorporating waste marble powder

Effects of pre-cracking on effectiveness of external fibre-reinforced polymer strengthening in unbonded prestressed beams

Interfacial bond behaviour between hybrid carbon/basalt fibre composites and concrete under dynamic loading

Experimental and numerical assessment of stress wave attenuation of metaconcrete rods subjected to impulsive loads

Re-evaluation of shear contribution of CFRP and GFRP sheets in concrete beams post-tensioned with unbonded tendons

Effect of hybrid fibers on shear behaviour of geopolymer concrete beams reinforced by basalt fiber reinforced polymer (BFRP) bars without stirrups

Experimental and Numerical Study of Basalt FRP Strip Strengthened RC Slabs under Impact Loads

Basalt fiber-reinforced polymer (BFRP) has been applied for strengthening concrete structures. However, studies on reinforced concrete (RC) slabs strengthened by BFRP strips under impact loads are limited in open literature. This study investigates the efficiency of using BFRP strips with various strengthening layouts and anchoring schemes on the impact resistance of RC slabs. A total of 11 two-way square slabs were prepared and tested, including one reference specimen without strengthening and ten slabs strengthened with BFRP strips and/or anchors. The RC slabs were impacted by a drop weight with increasing height until slab failure. The observed failure modes include punching shear failure, BFRP sheet debonding and reinforcement fracture. The failure modes and the effects of using various strengthening schemes on the impact resistant capacity of RC slabs were examined. The quantitative measurements, such as impact velocity, indentation depth and diameter, were compared and discussed. In addition, numerical studies were carried out by using LS-DYNA to simulate the impact tests of RC slabs with and without BFRP strengthening. With the calibrated numerical model, the impact behavior of slabs with various dimensions and strengthening layouts under different impact intensities can be predicted with good accuracy.

Lateral impact behaviors of concrete-filled double-steel tube with corrugated steel tube member(s)