SEBS-Polymer-Modified Slag–Cement–Bentonite for Resilient Slurry Walls

Abstract

In spite of the well-established design and construction approaches of slag–cement–bentonite slurry walls, the materials deteriorate inevitably in contaminated land. The development of effective materials which are sustainable, resilient and self-healing over the lifetime of slurry walls becomes essential. This study, for the first time, adopts a styrene–ethylene/butylene–styrene (SEBS) polymer to modify slag–cement–bentonite materials to enhance mechanical and self-healing performance. The results show that the increase in SEBS dosage results in significantly increased strain at failure, indicating the enhanced ductility thanks to the modification by the deformable polymer. The increased ductility is beneficial as the slurry wall could deform to a greater extent without cracks. After the permeation of liquid paraffin, the SEBS exposed on the crack surface swells and seals the crack, with the post-healing permeability only slightly higher than the undamaged values, which exhibits good self-healing performance. Scanning electron microscopy and micro-computed tomography analyses innovatively reveal the good bonding and homogeneous distribution of SEBS in slag–cement–bentonite. SEBS acts as a binder to protect the slag–cement–bentonite sample from disintegration, and the swollen SEBS particles effectively seal and heal the cracks. These results demonstrate that the SEBS-modified slag–cement–bentonite could provide slurry walls with resilient mechanical properties and enhanced self-healing performance.

Engineered spectrally selective and spatially segmented emittances for infrared camouflage textiles

“…2j, though there are several narrow absorption peaks at 1453 and 1378 cm −1 attributed to asymmetric methyl bending vibrations (–CH 3 ) and methylene wagging deformations (–CH 2 ), respectively, and 2918 and 2844 cm −1 associated with the stretching vibrations of –CH 2 . 53–57…”

“…The small narrow peak with an emittance of 0.9 at 3.4 μm is attributed to the stretching vibration of –CH 2 in SEBS molecules. 56…”

“…The small narrow peak with an emittance of 0.9 at 3.4 mm is attributed to the stretching vibration of -CH 2 in SEBS molecules. 56 The spectrally selective emittance not only facilitates effective IR camouflage but also harnesses radiative cooling, as evident in Fig. 4b.…”

“…2j, though there are several narrow absorption peaks at 1453 and 1378 cm À1 attributed to asymmetric methyl bending vibrations (-CH 3 ) and methylene wagging deformations (-CH 2 ), respectively, and 2918 and 2844 cm À1 associated with the stretching vibrations of -CH 2 . [53][54][55][56][57] Considering SEBS as an overcoating material, we hope to minimize its impact on both the IR camouflage and radiative cooling performance of the SET. Therefore, we must determine the optimal thickness of SEBS.…”

Durability, carbon footprint and contaminant immobilization in self-hardening slurries applied to cut-off walls: a review

“…rheology by the addition of sodium salts [60]) and/or the hardened slurry (e.g. ductility and crack-healing ability with polymers [61,62]).…”