Application of slag-alkali binders in jet cement grouting for soil consolidation

Abstract

Introduction. The study proves actuality of the problem connected with obtaining efficient slag-alkali binders for usage in soil jet cement grouting. Replacement of usual portland cement for a slag-alkali binder in geotechnical underground construction activities allows solving a problem of waste (slag) utilization and increase economic efficiency of the soil jet cement grouting. In view of cement grouting technology features and possibility of usage cementation mixtures with various engineering characteristics for different soil types, a broad nomenclature of slag-alkali compositions can be used for obtaining soil-concrete structures. Materials and methods. Different types of slag were studied as constituents of composite binders. The PTs 500 D0 cement was taken as the basic portland cement. Standard requirements for cementation mixtures of mixing and pump facilities for soil-concrete bodies became the criteria. Investigations of hydration and structure formation during hardening of slag-alkali binders and soil-concretes on their base were conducted using a system of physical and chemical methods. Evaluation of construction and engineering properties of the composite slag-alkali binder was accomplished in accordance with the methods as per GOST 10181-2014 and GOST 5802-86 state standards. Results. Results of analysis how the slag type and amount influence the physical and mechanical properties of the binder used for jet soil cementation are presented. The article shows improvement of physical, mechanical, process and usage properties of the slag-alkali binder. General mechanism of impact of the slag on properties of the cementation mixture were revealed. Conclusions. Efficiency of application of the slag as an active component of the composite binder for jet cementation in geotechnical construction was theoretically substantiated and experimentally demonstrated. General applicability of the obtained concrete mixture based on the slag-alkali binder is stated for usage in cementation methods of improvement of technical parameters of concrete mixture and concretes. A classification of expanding cements possessing various expansion degrees was suggested for solving different construction problems.

Thermal Technical Requirements for Wall Materials and Analysis of Thermal Stability of Enclosing Structures under Non-Stationary Heat Flow

“…Conglomerates based on these binders differ significantly from traditional Portland cement conglomerates, and this is due to the phase-mineralogical composition of the synthesized new formations. Investigating soil cements [4,5], still in the 50s of the 20th century,…”

“…Structural Engineering and Materials he drew attention to the fact that the substances formed during the hardening of soil cement in composition model the minerals of the Earth's crust, in particular zeolites and other minerals which at high temperatures recrystallize into nephelines, jadeites and feldspars, and by the nature of the synthesis process they are similar to the natural processes of mineral and rock formation. Based on the formulated scientific concepts of a number of scientists [4][5][6][7] it was found that the synthesis processes occurring in the Earth's crust are essentially similar to the industrial synthesis processes and the resulting conglomerates have increased durability and corrosion resistance. To obtain 1 ton of Portland cement, it is necessary to consume 179 kg of equivalent fuel and 110 kWh of electricity, and to obtain 1 ton of lime-silica binder -only 79 kg of fuel equivalent and 67 kWh of electricity [8].…”

Industrial waste products based concrete: environmental impact assessment

“…В настоящее время исследования направлены на получение многокомпонентных вяжущих с низкой долей портландцементного клинкера и бесклинкерных цементов на основе побочных продуктов промышленности [10][11][12]. Продукты гидратации этих вяжущих различаются химическим и минералогическим составом, а также структурой цементного камня на разных уровнях и, соответственно, свойствами [13][14][15].…”