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The compressive strength of the basalt fibre SCC was diminished by 28% at 500°C. The splitting tensile strength of the SCC was increased by adding 0.25% of fibre. Considerable degradation in the flexural strength of fibrous SCC was seen at 300°C. Slant shear of hybrid concrete was highly affected by fibre content of overlay. Interfacial surface roughened by sand blast provided proper bond in hybrid sample.

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This paper shows the results of an experimental study conducted to research the impact of waste marble powder (WMP) and fly ash (FA) on the fluidity (marsh cone flow time (MCFT), mini-slump diameter and plate cohesion meter (PCM)) and the rheological properties (viscosity and yield stress) of cement based grout (CBG) mixtures. The experiments were applied with the CBG mix including 1.00 water-binder (w/b) ratios and combined use of WMP (5-25%), FA (5-25%) and WMP+FA (10-30% + constant 25%). Test results illustrated that the rheological properties of the CBGs importantly have been improved by the addition of WMP, FA and WMP+FA to grout mix at w/b=1 ratio. Strongly shear thickening behaviour was got from the CBG mixtures the all WMP, FA and WMP+FA content. The increase in the percentage of WMP (5-25%) amount reduced the mini-slump flow diameter. Moreover, the increment in the percentage of FA (5-25%) amount increments the mini slum flow. According to the control sample, the increment in the percentage of WMP (10-25%) amount increased the mini-slump flow diameter for constant FA (25%) content. Also, the increase in WMP amount in the CBG mix, there is no effect on MCFT. Also, MCFT decreased with the increase of FA amount. Especially, FA increased the fluidity of CBG, when the WMP showed negative effect in increase the MCFT in WMP+FA content.

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The process of agro-industrial sewage treatment with the aim of extracting grease from the waters is studied by means of electroflotocoagulation. A method of optimising the construction of electroflotocoagulation apparatus for sewage treatment is offered that allows passing from a laboratorial model to an industrial specimen that possesses the same level of technological characteristics. Multiple examples are given of applying electroflotocoagulation technology for sewage treatment from proteins and grease under different conditions.

The automotive industry plays a major role in the worldwide economy and represents an opportunity to increase the performance of the Turkish economy. Phosphating units in the automotive manufacturing plants generate phosphate sludge as waste, which is classified as hazardous waste in the European Waste Catalogue. Phosphate sludge must be disposed of in licensed disposal plants according to the current environmental regulations. Solidification/stabilization (S/S) is a widely used treatment technology for the disposal of hazardous wastes. Portland cement is used for the solidification and stabilization processes to immobilize Ni and Zn in the phosphate sludge as well as to create construction material to be used as cobble stone for pavement. Examination of products obtained by S/S processes is performed for two points: to determine the quality and to assess the environmental impacts. The phosphate sludge samples are subjected to chemical characterization and a size distribution analysis leaching test. Concrete for cobble stone was produced by the S/S process with the addition of phosphate sludge to replace sand. Tests for the quality of the product were carried out to determine compressive strength, permeability, and elasticity. At the end of the leaching test, elution concentrations of Zn and Ni while using water with pH values of 4.0, 5.4, and 9.0 were determined to be under the limit of inert material properties. Use of phosphate sludge should be considered as a sand replacement in the proportion of 1% of phosphate sludge to cement in concrete production, such as for cobble stone for pavement, without any adverse environmental impacts.