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Inżynieria przedsięwzięć budowlanych na konferencjach krynickich 2022 i 2023: dokąd zmierzamy?

Kapliński Oleg

Przegląd Budowlany

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2023

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R. 94, nr 9-10

56--60

PL

W artykule dokonano oceny referatów z zakresu inżynierii przedsięwzięć budowlanych prezentowanych podczas konferencji krynickich. Szczegółowo omówiono referaty nadesłane w ramach części ogólnej konferencji w latach 2022 i 2023. Ocenę dokonano według triady: (a) jaki jest problem naukowy, (b) jaką przyjęto metodę, instrument badawczy, (c) jaki jest problem inżynierski? Zwrócono uwagę na dylematy badań, w tym samonakręcającą się spiralę trudności na ścieżce: zjawisko, metoda, badania, technologia i mechanizacja, mierniki oceny publikacji.

EN

The article evaluates papers in the area of engineering of construction projects, presented during the Krynica conferences. The papers submitted as part of the general field of the conferences in 2022 and 2023 were discussed in detail. The evaluation was made according to the triad: (a) what is the scientific problem, (b) what method, research instrument was used, (c) what is the engineering problem? Attention was paid to the research dilemmas, including the self-reinforcing spiral of difficulties on the path: phenomenon, method, research, technology and mechanisation, measures of evaluating publications.

2

Research on closed-loop utilization of engineering waste mud in engineering sites

Zhan Jinsheng, Zhao Shichun

Materials Science Poland

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2023

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Vol. 41, No. 3

99--110

EN

The large amount of waste mud generated during construction projects makes it difficult to implement closed-loop on-site treatment, resulting in the inability to achieve zero emissions, which not only wastes land resources but also pollutes the environment. This article first studied the flocculation effect and mechanism of two flocculants. Then, the treated sediment was used to prepare fluidized solidified soil, and the effect of flocculants in the sediment on the performance of fluidized solidified soil was studied. Finally, this technology of flocculation and re-solidification was applied in engineering. The results showed that the composite effect of adding PAC flocculant first and then APAM flocculant in the mud had the best mud-water separation effect. The soil was combined with the flocculants to prepare fluidized solidified soil that can effectively improve the strength and water stability of the solidified soil. Through engineering applications, it has been proven that closed-loop utilization of engineering waste mud can be achieved on-site. Therefore, this work provides a new method for achieving zero emissions through closed-loop utilization of engineering waste mud on-site and innovative experience for the construction of “waste-free cities”.

3

Key technologies and its application of gob-side entry retaining by roof cutting in a deep mine

Chen Shangyuan, Lv Qian, Yuan Yue

Archives of Mining Sciences

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2022

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Vol. 67, no. 1

55--77

EN

There are many problems associated with the surrounding rocks of the gob-side entry retaining by roof cutting (GERRC) as they are difficult to stabilise in deep mines. The following needs to be studied to understand the problems such as the pressure relief mechanism, evolution law of the surrounding-rock stress and the key technologies of GERRC in deep mines. Cracks are formed by advanced directional blasting to sever the path of stress transmission from the roof of the goaf to the roof of the entry and reduce the lateral cantilever length of the roof. Therefore the surrounding-rock stress and roof structure are optimised. The broken and expanded gangue formed by the collapse of the strata in the range of roof cutting fills the mining space adequately, which avoids a rapid pressure increase caused by the roof breaking impact and slows down the movement of overlying strata. The deformation of the deep surrounding rocks is transformed from “abrupt” to “slow”, and the surrounding-rock deformation of the retained entry in deep mines is significantly reduced. The average pressure and periodic pressure of the supports near the blasting line can be reduced by the blasting cracks to a certain extent, mainly due to the reduction of the length of the immediate roof cantilever and the effective load of the main roof. The combined support technologies for GERRC in deep mines were proposed, and field tests were performed. The monitoring results show that the coordinated control system can effectively control the deformation of deep rock masses, and all indexes can meet the requirements of the next working face after the retained entry is stabilised.

4

Współczesne badania wyładowań piorunowych i ich parametry stosowane w aplikacjach inżynieryjnych

Masłowski Grzegorz

Energetyka

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2021

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nr 11

728--734

PL

W artykule dokonano analizy częstotliwości występowania na Ziemi wyładowań troposferycznych na podstawie wskazań optycznego detektora OTD, który pracował na niskiej orbicie satelitarnej. Uzyskane rejestracje wykazały, że średnia częstotliwość wynosi 44 ±5 wyładowań/sekundę, a zatem jest ona o połowę mniejsza od tej, która została oszacowana na początku ubiegłego wieku. Zwrócono też uwagę na udział wyładowań atmosferycznych w funkcjonowaniu globalnego obwodu elektrycznego Ziemi. Dokonano analizy parametrów doziemnych wyładowań ujemnych i dodatnich ze szczególnym uwzględnieniem wyładowań głównych, prądu długotrwałego i prędkości przemieszczania się czoła fali prądowej w plazmowym kanale piorunowym. Zwrócono również uwagę na istotną zmianę w interpretacji parametru rocznej średniej gęstości wyładowań na kilometr kwadratowy.

EN

An analysis was made of tropospheric discharges occurrence frequency on the basis of indications from the OTD optical sensor which worked on a low satellite orbit. Obtained records showed that the average frequency was equal 44 ±5 discharges per second so it was less than half of that one which had been estimated at the beginning of the last century. Attenton was also paid to the participation of athmospheric discharges in functioning of the global Earth electrical circuit. Analysis was made of cloud-to-ground negative and positive discharges with particular reference to return strokes, continuing current and velocity of the current wave front travel in a plasma lightning channel. Pointed out was also the substantial change in the interpretation of the parameter referring to the average annual discharge density per square kilometre.

5

Analysis and application of filling mining technology in China’s mining area: a case study of Yuxing Coal Mine

Huang Dongmei, Xing Daqian, Chang Xikun, Zhu Yingying

Archives of Mining Sciences

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2021

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Vol. 66, no. 4

611--624

EN

According to the requirements of green mine construction and the coordinated development of environmental protection regulations, the existing filling technologies in China are compared and analysed. Several types of technologies are discussed, including the dry filling technology for gangue, grouting and filling for separated strata zones in overburden, grouting and filling technology for caving gangue fissures, paste and paste-like filling, high-water and ultra-high-water filling, and continuous mining and continuous filling. Then, the characteristics of these individual technologies are analysed. Through the analysis and comparison of these technologies, considering the requirements of green mine construction and coordinated development of environmental protection regulations, it was found that continuous mining and continuous filling technology is a feasible mean for constructing green mines and protecting the environment. In this study, the application of continuous mining and continuous filling technology in the Yuxing coal mine is introduced. Results show that surface subsidence was less than 80 mm, and the recovery rate of the working face reached 95%. This indicates that continuous mining and continuous filling technology can solve the problems of surface subsidence, environmental damage, and coal resource waste. Finally, the development prospects of continuous mining and continuous filling technology are proposed, providing theoretical and technical support for similar mining.

6

Stacje, działania i aplikacje inżynierskie w systemie DCS MASTER

Kieleczawa Antonina, Białecki Michał, Izakiewicz Radosław, Pietras Piotr, Skakowski Roman, Szubert Wojciech

Energetyka

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2020

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nr 12

655--661

PL

W artykule zostały ujęte wybrane zagadnienia dotyczące stacji inżynierskich i obsługi inżynierskiej systemu DCS MASTER. Z uwagi na ograniczony rozmiar artykułu nie sposób przytoczyć i opisać możliwe czynności inżynierskie przy tworzeniu, konfiguracji i eksploatacji systemów automatyki DCS MASTER. Tytułem ilustracji przedstawione zostały aplikacje inżynierskie do projektowania i edycji oprogramowania układów automatyki stacji procesowych MASTER oraz oprogramowania aplikacyjnego stacji operatorskich MASTER-Proster w zakresie schematów synoptycznych i paneli regulacyjno-sterowniczych, które wyraziście rzutują na komfort pracy przy przygotowaniu systemu do instalacji obiektowych. Podobnie przedstawiono walory wybranych możliwości konfiguracji stacji operatorskich w czasie przygotowywania do pracy, jak również eksploatacji obiektowej systemu. System DCS MASTER dostarcza znacznie szerszy zakres możliwości jego inżynierskiej obsługi niż przestawiono w artykule.

EN

Presented are selected problems concerning engineering stations and engineering operation of the DCS MASTER system. Considering the limited size of this article we are practically unable to quote and describe all possible engineering activities in the process of creation, configuration and operation of the DCS MASTER automation systems. By way of illustration described are engineering applications for designing and editing the software for automation systems of the MASTER processing stations as well as the application software for the MASTER-Proster operator stations in the range of synoptic diagrams and regulatory-control boards that distinctively impinge the working comfort during preparation of the system for object installations. Similarly presented are the advantages of selected possibilities of operator stations configuration during preparation for work as well as for the system object operation. But we must be also aware that the DCS MASTER system provides much wider range of its engineering operation than it is presented in this place.

7

An analytical design method for ductile support structures in squeezing tunnels

Wu Kui, Shao Zhushan, Qin Su

Archives of Civil and Mechanical Engineering

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2020

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Vol. 20, no. 3

396--408

EN

Ductile linings have been proved to be highly effective for tunnelling in heavy squeezing grounds. But there still has not been a well-established design method for them. In this paper, an investigation on an analytical design method for ductile tunnel linings is performed. Firstly, a solution in closed form for ground response of a circular tunnel within Burgers viscoelastic rocks is derived, accounting for the displacement release effect. Then based on the principle of equivalent deformation, the mechanical model of segmental shotcrete linings with yielding elements is established using the homogenization approach. Analytical prediction for behaviour of ductile tunnel linings is provided. Furthermore, the proposed design method for ductile tunnel linings is applied in Saint Martin La Porte access tunnel and the analytical prediction is in good agreement with field monitoring data. Finally, a parametric investigation on the influence of yielding elements on performance of ductile tunnel linings is conducted. Results show that the length of yielding elements poses a great influence on linings. It is feasible and effective to increase the length of yielding elements to obtain the pressure within the bearing capacity of linings. However, yield stress of yielding elements does not significantly affect the performance of the lining. It is suggested to apply yielding elements with relatively higher yield stress in linings for higher stability.

8

Pewna procedura stosowania liniowej wielowymiarowej analizy regresji do słabo uwarunkowanych danych eksperymentalnych

Kulisiewicz M., Piesiak S.

Zeszyty Naukowe Uczelni Jana Wyżykowskiego. Studia z Nauk Technicznych

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2016

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Nr 5

27--47

PL

W artykule przedstawiono pewien nowy sposób obliczeń parametrów modelu regresji. Polega on na odpowiednim sprowadzeniu regresji wielowymiarowej do regresji dwuwymiarowej poprzez wprowadzenie tzw. zmiennych zastępczych. Dzięki temu można łatwo wykryć wadliwe wyrazy, które mogą występować w macierzy obserwacji, a także bez trudu zweryfikować liniowość modelu regresyjnego. Jest to istotne zwłaszcza w przypadku tzw. układów słabo uwarunkowanych. Sposób ten i jego walory przedstawiono na licznych elementarnych przykładach numerycznych.

EN

The article presents a new method of the regression model parameters calculation. The procedure consists in a suitable reduction of multivariate regression analysis to two-dimensional regression by means of creating so-called substitute variables. Due to that it is easy to detect defective elements which can exists in the observation matrix and linearity of regression model can be easily verified. This is especially essential in case of so-called poorly conditioned systems. The method and its advantages are presented in a lot of elementary numerical examples.

9

Estymatory sygnału drganiowego w ocenie stanu technicznego silników spalinowych

Łukasiewicz M.

Logistyka

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2011

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nr 6

PL

Drgania zachodzą w każdym obiekcie mechanicznym, zwłaszcza wypełniającym swą funkcję celu w dynamicznie zmieniającym się otoczeniu (bądź obciążeniu – jak w przypadku silników spalinowych). Drgania te jednak zaczynają być istotne dopiero po przekroczeniu pewnego progu wyznaczanego przez amplitudę i częstotliwość zjawiska. Po przekroczeniu tego progu drgania mogą być szkodliwe dla obiektu, bądź dla jego otoczenia (np.: następuje zmniejszenie trwałości materiału). W praktyce badań diagnostycznych, wykorzystanie drgań umożliwia opis stanu dynamicznego maszyn za pomocą uszkodzeniowo zorientowanych różnych symptomów drganiowych. W pracy przedstawiono możliwości wykorzystania aplikacji inżynierskich do uzyskania estymatorów sygnału drganiowego, dzięki którym możliwy stanie się opis stanu technicznego obiektów mechanicznych.

EN

Vibrations occur in every mechanical object. Vibrations could be essential just after the crossing certain threshold marked by amplitude and the frequency of the phenomenon. They can be harmful for the object after exceeding this threshold of the vibration, or for his surroundings (e.g.: decrease of the durability of the material). The engineer application “Symptoms” allows to process the vibroacoustic signal from the vibration amplitude of time domain to the chosen estimators of the vibration process. The applicability possibilities of the application to the estimators obtainment of signal were introduced in this work.

10

Applications of Fuzzy Logic Methods to Disturbances Compensation in Processes of Fine Grinding

Kacalak W., Lipiński D., Krzyżyński T.

Machine Dynamics Problems

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2002

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Vol. 26, No. 4

93-100

EN

In the paper, a fuzzy system of compensation of position deviation of a grinding wheel in relation to a grinded work-piece is presented. An analytical solution of the problem of disturbances compensation requires a full description of the system properties. Greater problem complexity occurs in cases of an integration of grinding processes and smoothing of abrasive-resistant materials with auxiliary processes, as well as in cases of an automated grinding by means of many grinding wheels of different characteristics. It is advisable then to determine fuzzy relations and to work out a system of fuzzy compensation. Proposed algorithm of fuzzy compensation method considerably corrects a quality and stability of the fine grinding process.

11

Sposoby powtórnego wykorzystania zużytych opon we Francji

Królikiewicz M.

Elastomery

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2001

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T. 5, nr 4

25-30

PL

Omówiono problemy wynikające z nadmiernego gromadzenia zużytych opon we Francji. Przedstawiono niektóre sposoby powtórnego ich wykorzystania, szczególnie jako wypełnienia konstrukcyjne gruntu.

EN

The problems resulting from an excessive accumulation of worn out tyres in France have been discussed. Some ways of re-use, particulary engineering application have been presented.