scholarly journals Study of the Effect of Temperature Changes on the Elastic Modulus of Flexible Pavement Layers

2013 ◽  
Vol 5 (5) ◽  
pp. 1661-1667 ◽  
Author(s):  
Mohd Raihan Taha ◽  
Sentot Hardwiyono ◽  
Nur Izzi Md. Yusoff ◽  
Mohd Rosli Hainin ◽  
Jiantao Wu ◽  
...  
2022 ◽  
Vol 906 ◽  
pp. 69-76
Author(s):  
Tigran Petrosyan

In order to study the effect of temperature changes on the dissipative properties of materials, two approaches are used. The first approach implies introducing some temperature function under the sign of the integral in the heredity theory equation and simultaneously taking into account the dependence of the elastic modulus on temperature. As a result, based on experimental data on the thermal creep of soils, the expression for determining the hysteresis energy losses under the periodic voltage changes was obtained depending on temperature changes.According to the second approach, the expression for determining the hysteresis energy losses under isothermal conditions at different temperatures was obtained by introducing into the heredity theory equation an approximation of the experimental dependences of instantaneous deformation and temperature creep parameters for steel Kh18 N10T.


2018 ◽  
Vol 77 (6) ◽  
pp. 375-381
Author(s):  
K. M. Popov

Abstract. Influence of air temperature on the consumption of fuel and energy resources (FER) on train traction is due to a number of physical laws. The extent of this effect is specified in the Rules for Traction Settlement (RTS). At the same time, when rationing FER consumption for train traction, a specialized methodical base is used, which involves a different approach to accounting for the effect of temperature on FER consumption for train traction. At the same time in different documents of this base, the effects of low temperature on the absolute and specific consumption of fuel and energy resources on train traction are taken into account in a different way, which is due to the lack of consensus among specialists on the way this factor is taken into account. Specialists of JSC “VNIIZhT” carried out an analysis of a significant amount of driver’s routes data, results of which showed that the dependence of the specific flow rate on temperature, on the basis of which the corresponding influence coefficient is determined, needs to be periodically updated. In addition, when technically standardizing the consumption of fuel and energy resources (for the locomotive crew work site), the temperature effect coefficients need to be calculated for a specific work area and direction of motion on it, while using the average network coefficient values will lead to errors. When calculating additional flow of fuel and energy from the effect of temperature for electric multiple units (EMU), the equations of regression dependencies should be used, obtained by statistical processing of data on temperature changes and specific consumption of fuel and energy resources for EMU and determined for each series of EMU when working on a particular suburban area.


2021 ◽  
pp. 107754632110026
Author(s):  
Zhou Sun ◽  
Siyu Chen ◽  
Xuan Tao ◽  
Zehua Hu

Under high-speed and heavy-load conditions, the influence of temperature on the gear system is extremely important. Basically, the current work on the effect of temperature mostly considers the flash temperature or the overall temperature field to cause expansion at the meshing point and then affects nonlinear factors such as time-varying meshing stiffness, which lead to the deterioration of the dynamic transmission. This work considers the effect of temperature on the material’s elastic modulus and Poisson’s ratio and relates the temperature to the time-varying meshing stiffness. The effects of temperature on the elastic modulus and Poisson’s ratio are expressed as functions and brought into the improved energy method stiffness calculation formula. Then, the dynamic characteristics of the gear system are analyzed. With the bifurcation diagram, phase, Poincaré, and fast Fourier transform plots of the gear system, the influence of temperature on the nonlinear dynamics of the gear system is discussed. The numerical analysis results show that as the temperature increases, the dynamic response of the system in the middle-speed region gradually changes from periodic motion to chaos.


Author(s):  
Yiqun Huang ◽  
Pawan Singh Takhar ◽  
Juming Tang ◽  
Barry G Swanson

Rheological behaviors of high acyl (HA) gellan are not well understood partially because of its relatively late commercialization compared to low acyl gellan. The objective of this study was to investigate the effect of temperature (5-30 °C), calcium (0, 1 and 10 mM) and gellan concentrations (0.0044-0.1000% w/v) on the flow behaviors of high acyl gellan aqueous solutions using rheological tests. Gellan solutions with 0 or 1 mM added Ca++ exhibited shear thinning behavior at gellan concentrations above 0.0125%. The influence of temperature on apparent viscosity (shear rate, 100 s-1) of gellan solutions can be described with an Arrhenius relationship. The apparent viscosity of gellan solution at low concentrations was more sensitive to temperature changes. The addition of Ca++ led to a decrease in flow resistance for a dilute gellan solution (<0.0125%), but an increased resistance for a relatively concentrated gellan solution (>0.0125%).


2020 ◽  
Vol 3 (4) ◽  
pp. 1077
Author(s):  
Leonardo Lijuwardi ◽  
Gregorius Sandjaja Sentosa

ABSTRACTMulti-layer systems theory is one of the concepts used in finding out the amount of strain and stress that occurs in the road pavement system due to vehicle loads. The purpose and goal of this study is to analyze the amount of strain that occurs on the pavement systems in Indonesia, especially in the subgrade position. The type of multi-layer system theory used to calculate the amount of strain includes the theory of one layer systems, two-layer systems and three-layer systems with data analyzed in the form of pavement thickness and type of pavement material.Based on this study, the value of strain obtained by the theory of one-layer system in some of the road data reviewed are 533.8658 microstrains, 361.3456 microstrains, 1577.987601 microstrains, 618,012 microstrains and 140.3075 microstrains. For research with two-layers systems, the results obtained are 1116.2920 microstrains, 544.322 microstrains, 1448.0839 microstrains, 734.1844 microstrains and 738.7226 microstrains. For research with three-layers system, results obtained are 72.20275278; 70.80346908; 192.9638366; 123.1150377dan 391.8845636 microstrains. The results with the calculation of one-layer system are very large because the modulus values of the subgrade layers are not reviewed and only pavement thickness is reviewed. As for calculations with the theory of two-layer systems, the results obtained are far greater than one-layer systems, due to the limitations of the graph to find the value of the ratio between thickness and large contact area. Calculation with the theory of three-layers system is a strain calculation which has a much smaller value compared to the theory of one-layer system and two- layer system. This is because this theory divides the calculated pavement layers into three layers, which is in accordance with the flexible pavement system which divides the pavement layers into three layers, so this calculation is the most ideal calculation because it approaches its original condition.ABSTRAKTeori sistem lapis banyak merupakan salah satu konsep yang digunakan dalam mencari tahu besaran regangan dan tegangan yang terjadi pada sistem perkerasan jalan raya akibat beban kendaraan. Maksud dan tujuan dari penelitian ini adalah untuk menganalisis mengenai besaran regangan yang terjadi pada jalan raya di Indonesia pada lapisan tanah dasar khususnya di posisi permukaan tanah dasar. Adapun jenis teori sistem lapis banyak yang digunakan untuk menghitung besaran regangan tersebut antara lain teori one-layer systems, two-layers systems dan three-layers systems dengan data yang dianalisis berupa tebal perkerasan dan jenis material perkerasan jalan.Berdasarkan penelitian ini, adapun nilai dari regangan yang diperoleh dengan teori one-layer system di beberapa data jalan yang ditinjau, antara lain 533.8658 mikrostrain, 361.3456 mikrostrain, 1577.987601 mikrostrain, 618.012 mikrostrain dan 140.3075 mikrostrain. Untuk penelitian dengan two-layers system diperoleh hasil yaitu 1116.2920 mikrostrain, 544.322 mikrostrain, 1448.0839 mikrostrain, 734.1844 mikrostrain dan 738.7226 mikrostrain. Untuk penelitian dengan three-layers system diperoleh hasil antara lain 72.20275278; 70.80346908; 192.9638366; 123.1150377 dan 391.8845636 mikrostrain. Hasil dengan perhitungan one-layer system sangat besar dikarenakan nilai modulus lapisan dari subgrade tidak ditinjau dan hanya meninjau tebal perkerasan. Adapun untuk perhitungan dengan teori two-layers system, hasil yang diperoleh jauh lebih besar daripada one-layer system, yang disebabkan keterbatasan dari grafik untuk mencari nilai perbandingan antara ketebalan dan luas kontak yang besar. Perhitungan dengan teori three-layers system merupakan perhitungan regangan yang memiliki nilai jauh lebih kecil dibandingkan dengan teori one-layer system dan two-layer systems. Hal ini dikarenakan teori ini membagi lapisan perkerasan yang dihitung menjadi tiga buah lapisan, yang sesuai dengan sistem perkerasan lentur yang membagi lapisan perkerasan menjadi tiga buah lapisan, sehingga perhitungan ini merupakan perhitungan yang paling ideal karena mendekati kondisi aslinya.


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