Mortar

About: Mortar is a research topic. Over the lifetime, 25024 publications have been published within this topic receiving 218739 citations.

The effect of bentonite/cement mortar for the stabilization/solidification of sewage sludge containing heavy metals

Abstract: This study examines stabilization/solidification (S/S) techniques using a bentonite/cement mortar. These techniques are usually applied for the stabilization of sewage sludge, containing heavy metals such as Cu, Zn, Pb. Due to the high organic content of sludge, bentonite had been added in order to stabilize the system. For this purpose, 4 × 4 × 16 cm mortar prism samples were prepared. Their composition was: 50% w/w sewage sludge (primary sewage sludge from Psyttalia Athens and secondary biological sewage sludge from Metamorphosis Athens), 30% w/w cement CEMI 42.5 and finally 20% w/w bentonite. The samples were cured for 28 days at 25 °C and compressive strength was tested. Highest strength and lowest leachability were the criteria for selection of the optimum product by the S/S technique. An extensive study using several characterization techniques focusing on hydration reactions was carried out. The instrumental analysis included: X-ray diffraction analysis, thermal analysis (TGA, DTA), electron scanning microscopy (SEM), infrared analysis (FT-IR) as well as tests for the toxicity characteristic leaching procedure (TCLP). The S/S products had been proven throughout the study as a viable solution for stabilizing heavy metals. They can be used in many applications such as in landfill liners, slurry walls and building blocks.

Flexural Strengthening of Two-Way RC Slabs with Textile-Reinforced Mortar: Experimental Investigation and Design Equations

Abstract: The application of textile-reinforced mortar (TRM) as a means of increasing the flexural capacity of two-way reinforced concrete (RC) slabs is experimentally investigated in this study. The parameters examined include the number of TRM layers, the strengthening configuration, the textile fibers material (carbon versus glass), and the role of initial cracking in the slab. For this purpose six large-scale RC slabs were built and tested to failure under monotonic loading distributed at four points. It is concluded that TRM increases substantially the precracking stiffness, the cracking load, the postcracking stiffness, and eventually the flexural capacity of two-way RC slabs, whereas the strengthening configuration plays an important role in the effectiveness of the technique. Simple design equations that provide good estimation of the experimental flexural moment of resistance are proposed.