Modern soil stabilization methods in condition of a dense urban Research Paper

Modern soil stabilization methods in condition of a dense urban environment - Research Paper Example The present study is focused on the methods of soil stabilization, the modern day techniques and materials that are available, and the need and understanding of the methods such that soil stabilization in the urban dense areas can be successfully achieved improving the conditions of the soil, increasing their strength and making them more capable of bearing loads. Introduction: Stabilization of soil refers to the process of soil treatment through the use of chemicals or mechanically. This is primarily done to improve the engineering properties of the soil. The chemical materials that are in common used for the purpose include lime, fly ash, and cement. Mechanical substances include geotextiles and geogrids. The use of cement treated bases generally assists in upgradation of the quality of the soil. There are several reasons for the need of soil stabilization. These essentially include the strengthening of the soil since stabilization of soil increases the strength of the soil that is already in existence thereby improving its capacity to bear loads. Also, soil stabilization enables control of dust and allows waterproofing of the soil. With control in dust, the dust that is generated as a result of use of different tools and instruments may be eradicated. Waterproofing enables preservation of the natural strength of soil by preventing the entry of water travelling from the surface (Ana, 2011). Mechanical or additive methods are the two most significant methods that can be used for soil stabilization. The blending of the materials used is highly essential in this regard since it determines the effectiveness of the stabilization. A stationary or travelling plant is usually considered to be preferable for the mixing whereas other methods like scarifies, plows, disks, graders, and rotary mixers are also used. The amount of stabilization required as well as the environment and prevailing conditions of the site determine the method that may be used for stabilization. Mechanical stabilization mixes soils of two different gradations that result in the desired soil specificity. In the additive method, the use of an additive which when added into particular amounts leads to improvement of the soil. Apart from mechanical and additive measures, soil stabilization might also be achieved through cementing or by modification. The cementing process makes use of chemicals for hardening the soils. In the process of modification, the compacting, mechanical blending, addition of cementing materials in small amounts, or addition of chemical modifiers are done to achieve the stabilization of the soil (Ana, 2011). With understanding the needs of stabilization of soils, and the different methods available for the process of soil stabilization, the present study focuses on the modern methods of soil stabilization that may be applied in the dense urban environments. Literature Review: Day et al (2010, pp.193-195) in their studies reflected on the association of the root and soil in the urban environment which they considered to be critical not only for the lives of trees but also for the functions of the ecosystem in the urban areas as well. The importance of trees and hence the significance of soil stabilization has been considered in these studies. Hence conditions in a particular urban environment that includes the compactness of the soil, and other factors associated with underground infrastructure, contamination, etc are essential for the development of the

Chemistry Assignment Example | Topics and Well Written Essays - 250 words

Chemistry - Assignment Example Question 1: En=-(13.6eV*z ²)/n ², because z=4 it can be written as En=-16*13.6eV / n ² ii) the dependence of quatum numbers n upon l is given by the following formula l=n-1 ÃŽ £2(2*l+1)=2* n ² iii) n=2 for beryllium, so l=1 and can not be 3 d) iii) energy emitted by photon: |Einf- E2|= 0+54.4eV=54.4 eV= 54.4*1.6*10^-19 [J]=8,7*10^-18 [J] 8,7*10^-18 [J] now we should express photon’s frequency from it’ energy: E=h*f => f=E/h f= 8,7*10^-18 [J]/6.63*10^-34 [J*s]=1.31*10^16 [1/s] 1.31*10^16 Hz is ultraviolet spectrum iv) the energy of the lowest energy photon which can be absorbed by beryllium ion is: E2-E1=-54.4eV+217.6=163.2 eV v) it could absorb a photon of a lower energy if its electron was on a higher energetic level i) E1=-16*13.6eV / 1=-217.6eV E2=-16*13.6eV / 4= -54.4eV E3=-16*13.6eV / 9 = -3.067eV Eoo=-16*13.6eV/inf = 0 Question 3 - because ΔH>0 (=29kJ) reaction is endothermic; - I2+Cl2 =2ICL (-29kJ) ΔH=2ΔHICL-ΔHCl2-ΔHI2; - equilibrium will not change as the number of molecules in the left part of the equation equals to the number of molecules in the right part of the equation: I2+Cl2 =2ICL 1+ 1=2 - because it’s endothermic reaction the increase of temperature will cause the shift of equilibrium to the right (forming of ICl); - the reaction will pass faster with the following rate lg (k^(T2/T1)) where k is the reaction rate coefficient; - the presence of catalyst will cause the reaction rate to increase, the equilibrium will cause the shift to the right (forming of ICl) as catalyst mainly reduces activation energy.