PLANNING AND DESIGN OF EXPRESS LANES CONNECTING TWO HIGHWAYS IN MIAMI, FLORIDA, USA

Rising traffic and congestion in urban areas increases a demand for long bridges and interchanges. However, construction and designing such bridges evolve the infrastructure due to being permanently affected by safety, environment and budget. Therefore, there is a variety of bridge construction types that are chosen depending on the location and several parameters such as feasibility, safety maintainability, cost, and simplicity of construction. Over 60 years, precast prestressed concrete girders have been widely used all over the USA owing to their low life-cycle cost, endurance and modularity..

Response of beams resting on linear and nonlinear elastic foundations and subjected to harmonic high-speed moving loading

Analytical solution technique that provides fast, efficient and accurate results is developed for the fourth-order nonlinear differential equations describing the transverse vibrations of a beam on an elastic foundation. The method of solution developed is based on a recent novel method of calculation, the Adomian Modified Decomposition Method (AMDM). AMDM has advantages of solving without discretization, linearization, perturbation, or a priori assumptions, all of which has the potential to change the physics of the problem. The accuracy and the convergence speed of the method are validated against exact solutions. The beam is analyzed using two existing beam theories, namely, Euler-Bernoulli and Timoshenko beam theories. For the foundation widely used one-parameter Winkler and two-parameter Pasternak foundations are used. Numerical calculations of vibration frequencies and mode shape functions are performed. Effect of a foundation parameters and loadings on beam vibrations are analyzed and discussed

Free Vibrations with Large Amplitude of Axially Loaded Beams on an Elastic Foundation Using the Adomian Modified Decomposition Method

Analytical solutions describing free transverse vibrations with large amplitude of axially loaded Euler–Bernoulli beams for various end restrains resting on a Winkler one-parameter foundation are obtained using the Adomian modified decomposition method (AMDM). The AMDM allows the governing equation to become a recursive algebraic equation, and, after some additional simple mathematical operations, the equations can be cast as an eigenvector problem whose solution results in the calculation of natural frequencies and corresponding closed-form series solution of the mode shapes. Important to the use of the Adomian modified decomposition method is the treatment of the nonlinear Fredholm integral coefficient, which forms part of the governing equation. In addition to the calculation of natural frequencies and mode shapes, investigations are made of the effects on the free vibrations of the Winkler parameter and of increasing the axial loading

PLANNING AND DESIGN OF EXPRESS LANES CONNECTING TWO HIGHWAYS IN MIAMI, FLORIDA, USA

Rising traffic and congestion in urban areas increases a demand for long bridges and interchanges. However, construction and designing such bridges evolve the infrastructure due to being permanently affected by safety, environment and budget. Therefore, there is a variety of bridge construction types that are chosen depending on the location and several parameters such as feasibility, safety maintainability, cost, and simplicity of construction. Over 60 years, precast prestressed concrete girders have been widely used all over the USA owing to their low life-cycle cost, endurance and modularity..

Environmental indemnity: seeking effective mechanisms for ensuring the participation of law enforcement agencies

Currently, there is an increase in the number of environmental violations and the environmental damage they cause. The article presents the results of the study of the legal framework and the practice of law enforcement to determine environmental damage, its scope, and possible compensation. The objective is to define the powers, functions, and roles of the agencies responsible for enforcing the law to guarantee environmental compensation. It is studied from the bibliographical, analytical, and critical review of the legal regulation, the practice of applying the law, and the scientific opinions on the compensation for damage to the environment. It is concluded that adequate environmental compensation depends directly on the activities of law enforcement agencies to identify and suppress environmental crimes and carry out administrative or criminal proceedings against offenders. The particularities of filing a civil lawsuit as a tool to repair the damage caused by an environmental crime are considered, focused on organizational and legal issues that negatively affect the effectiveness of environmental rights protection, as mentioned above, including the environmental incompetence of those who investigate crimes in that sphere and the shortcomings of judicial practice in determining the environmental damage. The main mechanisms to ensure the participation of law enforcement agencies in the calculation of environmental compensation, which has been developed in world practice, are presented. The authors made proposals for improving the existing organizational and legal framework and leveling the shortcomings of law enforcement practice

Використання технологій стабілізації електрофізичних характеристик сенсорних конструкцій при розробці та виробництві вимірювальних перетворювачів

The object of the study is the design, manufacturing technology and methods of stabilizing the electrophysical characteristics of measuring transducers. The problem solved in the research is the creation of methods and design and technological solutions to ensure stability used in the development and manufacture of measuring transducers. As a result of the conducted research, designs and technologies for manufacturing and stabilizing the electrophysical characteristics of measuring transducers were developed. The features of the developed designs of measuring transducers are increased in comparison with the known time stability with a basic error of no more than 0.1 %/year. Technologies for stabilizing the parameters of measuring transducers, in contrast to the known ones, differ in their versatility, since most elastic elements that perceive mechanical magnitude are membranes and beams, on which thermocompensating films are easily applied. The stabilization of the parameters of the entire measuring transducer, unlike the known ones, is carried out after the removal of internal mechanical stresses of each element and part of the measuring transducer through the integrated use of current and vibration dynamic loads. Thus, the use of complex compensation due to the application of a new method of compensation of internal mechanical stresses in the structure, based on the use of multilayer film compositions formed on sensitive elements, followed by thermal and vibration stabilization of measuring transducers. In addition, reducing the measurement error and increasing the time and parametric stability of the measuring transducers is achieved through the use of specialized heat treatment modes, training resonant vibration and current loads. When developing structures and stabilization methods, previously developed engineering mathematical models were used, including constructive, informational, dimensional, technological and circuit engineering. At the same time, depending on the adopted design and the technology used, engineering models were modified by including known coefficients and dependencies. This method has significantly reduced the cost and complexity of developmentОб’єктом дослідження є конструкція, технологія виготовлення та методи стабілізації електрофізичних характеристик вимірювальних перетворювачів. Завданням, що вирішується в дослідженнях, є створення методів і конструкторсько-технологічних рішень для забезпечення стійкості, що використовуються при розробці та виготовленні вимірювальних перетворювачів. В результаті проведених досліджень розроблено конструкції та технології виготовлення та стабілізації електрофізичних характеристик вимірювальних перетворювачів. Особливості розроблених конструкцій вимірювальних перетворювачів підвищено в порівнянні з відомими стабільністю в часі з основною похибкою не більше 0,1 %/рік. Технології стабілізації параметрів вимірювальних перетворювачів, на відміну від відомих, відрізняються своєю універсальністю, оскільки більшість пружних елементів, що сприймають механічні величини, це мембрани та балки, на які легко наносяться термокомпенсуючі плівки. Стабілізація параметрів всього вимірювального перетворювача, на відміну від відомих, здійснюється після зняття внутрішніх механічних напружень кожного елемента і частини вимірювального перетворювача шляхом комплексного використання струмових і вібродинамічних навантажень. Таким чином, використання комплексної компенсації обумовлено застосуванням нового методу компенсації внутрішніх механічних напружень у конструкції, заснованого на застосуванні багатошарових плівкових композицій, сформованих на чутливих елементах, з наступною термо- та вібраційною стабілізацією вимірювальних перетворювачів. Крім того, зниження похибки вимірювання та підвищення часової та параметричної стабільності вимірювальних перетворювачів досягається за рахунок використання спеціалізованих режимів термообробки, тренування резонансної вібрації та струмових навантажень. При розробці конструкцій і методів стабілізації використовувалися раніше розроблені інженерні математичні моделі, у тому числі конструктивні, інформаційні, розмірні, технологічні та схемотехнічні. У той же час, в залежності від прийнятого дизайну і використовуваної технології, інженерні моделі були модифіковані шляхом включення відомих коефіцієнтів і залежностей. Такий метод значно здешевив і трудомісткість розробк