Waterproofing of primary lining in tunnel using nano chemicals and soil modifiers in Concrete

The use of waterproofing chemicals in the field of concrete technology has proven a significant boom in the civil engineering industry by increasing the life of concrete structures. The materials such as nano-acrylic polymers resulted, significant control over the water leakage and damping conditions especially Terrasil and Zycobond and various nano sealers such as Zycoprime+ and Zycosil+. In this study, the primary focus is to waterproof tunnels using the various acrylic, nano-technological, and soil modifier chemicals to stabilize the tunnel structure in areas of hilly terrain. The use of these chemicals has been sourced in other areas of application but the least glance is seen in the field of tunnel engineering. These chemicals bind with the concrete and form a hydrophobic layer thus decreasing the permeability of concrete structure. In the present study the percentage of Zycobond and Terrasil used was 1.5% by weight of concrete and the ratio for Zs+:Zp+:water was 1:2:20. Tunnels especially in hilly terrain pass the flowing streams, thus making it more prone to damping conditions. So, poor site conditions result in less durability of concrete as well as steel, therefore improvement in engineering properties using these chemicals is primarily sought out in this paper. The factors considered during the use were the permeability, strength, volumetric analysis of chemicals, material properties etc. Water-proofing the concrete improves various engineering properties such as permeability, compressive strength, durability, strength, and various other properties of Concrete. The study emphasized to gauge the viability of Zycosil+ and Zycoprime+, Terrasil and Zycobond as waterproofing agents in concrete.

LAB-SCALE TESTS OF INCOHERENT ROCK REINFORCEMENT USING TWO-COMPONENT POLYMER BLENDS

The study addresses improvement of physical and mechanical properties of incoherent sediments by means of their chemical reinforcement using two-component resins. The lab-scale testing data on reinforcement of fine-grained quartz sand using two-component activated mineral and polyurethane resin blends are presented. Resins were injected by two ways on the tests. The first method was sequential injection of the polymer blend components in rock samples. The second method was injection of finished polymer blends. The two-component activated mineral and polyurethane resin blends ensure more effective reinforcement of incoherent sediment rocks as against foamed polyurethane blends. The uniaxial compression strength of reinforced fine-grained sand is 2.5-3 times higher in case of sequential injection of the components than in injection of finished mixtures. The elasticity modulus of the reinforced samples is 5.5-6 times higher in sequential injection than in injection of finished blends. The test results are useful for selection and optimization of injection method for two-component polymer blends in stabilization of broken rocks and in water-proofing of underground excavations.

PREDICTING THE STATE OF THE ICE BARRIER OF A VERTICAL MINE SHAFT UNDER ARTIFICIAL THAWING

At the end of the shaft penetration under the protection of the ice barrier and the termination of the process of freezing the rocks, the transition period from freezing to thawing begins. First of all, the tubing support of the trunk and the layer of rocks adjacent to the concrete support are subjected to thawing. At this time, water is pumped through the grouting holes in the tubing to check the tightness of the tubing column, after which the grouting is performed with cement mortar of the fixed space. Thus, grouting is an integral part of the work on waterproofing the support. For successful work on grouting, it is necessary to ensure the thawing of the ice barrier by a value of 1 m from the contour of the trunk in the sinking. The necessary defrosting can be provided in various ways, including the circulation of warm air in the barrel, the supply of warm coolant to the freezing columns, etc. A program for calculating the defrosting parameters has been developed, depending on the combination of methods for supplying warm air and heated brine. It is determined that in order to create reliable conditions for the production of plugging of the fixing space and water-proofing of the tubing support, the most favorable option is thawing by feeding warm air into the barrel and circulating the coolant at a temperature of +15°C.

Effect of Water Proofing Materials on Self-Healing Concrete

Improving the strength of the concrete structures and increasing the service life is an important issue. The service times of the concrete remained; external factors such as water penetrating into these micro-cracks and shorten the life of the concrete. In order to solve this problem, the idea of self-healing concrete with bacteria or other materials has been put forward and studies have shown that using CaO based materials that repair cracks in this direction by precipitating calcite. It is obvious that long term performance of concrete will increase with to prevent water pass to concrete interior. Instead of forming a barrier on the positive or negative side of concrete, water proofing admixture turn the concrete itself into a water barrier. Internal concrete waterproofing systems can be water repellents or crystalline admixtures. In this study, water proofing admixture was added to concrete mixture as water proofing material and its effect on self-healing in terms of filling the pores was investigated. Beam samples including the CaO based water proofing powder materials were produced in size of 285x75x25 mm. The samples were cracked in the flexural machine. After some days, the cracks were investigated by microscope. Crak control was continued till 28 days. At the end of study, the cracks smaller than 0.3 mm were self-healed. However, the bigger cracks than 0.3 mm cannot be self-healed by water proofing material. Consequently, self-healing of concrete with CaO based water proofing powder material is very promising for the environmentally friendly and sustainable structures of the future.

Treated Textile Electrostatic Properties Study

In the article research results are presented, which aim to provide treated textile electrostatic properties study. In the article research results are presented, which aim to provide find out abilities of an anti-electrostatic treatment and binding agents for it in treatment of special textile materials and their dependance from modes of operating textile washing. Results of determine a composition and abilities of a functional impregnation; develop a method to study values of electrostatic field for tribocharging conditions of textile materialsare; experimental studies of electrostatic values of materials with functional treatment depending on operating washing modes also presented here. Study results allowed to establish efficiency of the proposed combination of anti-electrostatic active composition based on 5 % solution of dialkyldimethylammonium chloride with a binding agent with the effect to preserve the treatment in the material structure and content of which is 4 % in application of textile fabric with widely used fiber content (cotton 53 %, polyester + oil and water-proofing finish). Acrylic dispersion is stable film-forming component suitable in preserving anti-electrostatic treatment on the surface of a textile material. The research was made in Don State Technical University within the framework of State Assignment of the Ministry of education and science of Russia under the project 11.9194.2017/BCh.

Application of Oobleck as a Speed Breaker

A fluid in which the shear stress is directly proportional to strain, then it is termed as a Newtonian law of viscosity. If a fluid which does not obeys this law, then it is named as a Non -Newtonian fluid and Oobleck is one of the non -Newtonian fluid i.e.., (shear stress is indirectly proportional to the velocity gradient) and Oobleck is made by mixing the corn starch and boiled water in the appropriate ratio of 1:1.25 to get the non -Newtonian fluid property. Then, the mixture made is stored in water proofing packaging material i.e., Kevlar fiber and it is used as replacement of existing conventional speed breaker. The aim of this project is to apply the Oobleck mixture for a speed breaker, study about it’s characteristics and compare it with Conventional as well as plastic speed breaker. It plays a major role in controlling the speed of the vehicle and helps in preventing the accidents. The Oobleck is stored as a packing material in Kevlar fiber which retains the properties of the inner material forever and is having low thermal conductivity and chemical reactivity. The result indicates that the usage of Oobleck in speed breaker is sensitive to the speed of the vehicles and cost of manufacturing Oobleck speed breaker is comparatively lower than the conventional speed breaker.