scholarly journals Classification and determination of working area of concrete placing booms

2018 ◽  
Vol 251 ◽  
pp. 03028
Author(s):  
Yevgeny Koshkarev

A concrete placing boom is the final element of concrete mixture pipeline transportation system. It is designed to deliver the concrete mixture for discharging where and when required, therefore, similar to cranes, it must be equipped with at least two mechanisms: boom extension and rotation. The mechanisms can be both manually and hydraulically actuated, hence, booms are differentiated between mechanical (manually controlled) and hydraulically or electrically controlled. This article aims at describing the areas for using various categories of concrete placing booms.

2013 ◽  
Vol 25 (6) ◽  
pp. 3487-3490
Author(s):  
Xiaodong Shao ◽  
Xinli Han ◽  
Guangsan Song ◽  
Xiaodong He ◽  
Yangqin Liu ◽  
...  

2013 ◽  
Vol 753-755 ◽  
pp. 2916-2919
Author(s):  
Yang Wang ◽  
Qing Lin Cheng ◽  
Xian Li Li ◽  
Xi Yi

Pipeline transportation is the most important transport mode for crude oil. When oil pipeline operates at low throughput or shutdown, congelation accident always happen as the temperature of oil in pipeline drops, which causes malignant accidents and significant financial losses. Study of the various factors affecting congelation failure is necessary. According to the statistics and analysis of congelation accident, direct and indirect reasons of affecting pipeline congelation failure were determined. Combining with fuzzy comprehensive assessment method, the related importance of factors on congelation accident was studied, and the grade of factors affecting failure congelation of pipeline was also identified. Aiming at the factors, some improvement measures were put forward. These can provide evidences for accident treatment, planned maintenance, security operation and scientific management.


2011 ◽  
Vol 71-78 ◽  
pp. 3016-3019
Author(s):  
Yan Fei Liang ◽  
Wei Ming Tan ◽  
Qing Dan Yuan

Structure of dusty feeder on the principle of negative pressure was discusses. From the practical design of a pneumatic transportation system in charging solid dusty material, the process data and property parameters used as the base in design were indicated. The selection of process, the determination of the parameters and the calculation of the transportation piping were described in detail, providing a theoretical basis for the mechanical use of rubber and other industries.


2019 ◽  
Vol 18 (4) ◽  
pp. 319-329
Author(s):  
I. I. Palevoda ◽  
S. M. Zhamoidzik ◽  
D. S. Nekhan ◽  
D. S. Batan

The paper presents a complex of laboratory and theoretical studies of physical and mechanical properties in centrifuged concrete while using samples of sectoral cross-section which are cut in layers from a finished product. A post made of concrete having B40 grade for compression strength and manufactured while using centrifugation with the help of РТЦ-5 machine. Assessment of heterogeneity across section thickness has been carried out by visual determination of composition changes in cross section, determination of strength, density of the obtained concrete samples, and water content over cross section of concrete mix. According to the results of a visual study on composition of a concrete structure it has been revealed that 1/8 part of the structure (from an inner surface) does not have a large aggregate. Later, as it moves to periphery, there is an increase in coarse aggregate and a decrease in size and number of cells between grains of gravel. An analysis of experimental data has shown that properties of the centrifuged concrete in samples being sawn in layers change significantly: density of concrete in samples of an inner layer is lower by 8 % than in samples of an outer layer, and compressive strength of concrete – by 34 %, water content of concrete mixture of samples of the inner layer has turned out to be by 43 % higher than in samples of the outer layer. Approximating curves showing regularities of changes in density, concrete strength, water content of concrete mixture over thickness have been constructed in the paper. Linear and exponential equations have been obtained that describe changes in physical and mechanical properties of centrifuged concrete over section depending on structure properties as a whole, which, taking into account the obtained correction factors k1 and k2, can be used with an acceptable level of confidence in practical calculations of centrifuged concrete structures. Relationship between strength of centrifuged concrete varying over cross section and action of a centrifugal force of inertia has been revealed in the paper. An equation has been obtained that relates the strength of centrifuged concrete to its density. Analysis of the research results makes it possible to assert that the main source of loading perception in centrifuged concrete structures is outer layers.


2018 ◽  
Vol 4 (1) ◽  
Author(s):  
Zihan Risman ◽  
Yunianto Setiawan ◽  
Ika Meicahayanti

Pasar Loa Kulu beroperasi setiap hari mulai pukul 06.00  – 17.00 WITA dan dikelola oleh Unit Pengelola Pasar. Pengelolaan sampah di pasar ini belum terkelola dengan baik sehingga perlu adanya pengelolaan. Tujuan dari penelitian ini adalah mengetahui karakteristik sampah dengan merancang dan merekomendasikan pengelolaan sampah pada sistem pemilahan, pewadahan, pengumpulan, dan pengangkutan sampah. Sistem pemilahan dan pewadahan dilakukan dengan menghitung jumlah timbulan dengan hasil rata-rata 540,62 kg/hari dan karakteristik sampah berupa sampah organik sebanyak 492,95 kg/hari dan anorganik 47,66 kg/hari. Direkomendasikan dengan memberikan bak sampah berdasarkan karakteristik agar tidak tercampur. Sistem pengumpulan dilakukan dengan mengumpulkan sampah dari bak sampah hingga ke truk dan ditentukan alternatif rute pengumpulan sampah. Dibuat 3 alternatif rute pada bak sampah belakang dan rute optimum berada pada rute 1. Bak sampah depan dari 2 rute alternatif dipilih rute 2 sebagai rute optimum. Sistem pengangkutan dilakukan penentuan alternatif rute yang efektif dan efisien dengan menggunakan perangkat lunak Arcgis 10.1. Sistem pengangkutan direncanakan dibuat celah pada bak truk sampah antara sampah organik dan anorganik dan dibuat 3 rute alternatif dari Pasar hingga ke TPA Bekotok. Sehingga dipilih rute 1 sebagai rute yang efektif dan efisien.Kata kunci: Pasar, Pemilahan, Pewadahan, Pengangkutan, Pengumpulan. Loa Kulu market operate every day starting at 06.00–17.00 WITA and managed by Unit Market Managers. Waste management in the market has not managed well by  market manager so that required management. The purpose of this research is knowing characteristic garbage to design and recommends waste management on system sorting, containers, collection, and disposal. The system sorting and containers done by counting the number of  pileup with the results average 540,62 kg/day and characteristic of the waste in from organic waste as many as 492, 95 kg/day and inorganic 47,66 kg/day. Recommended by giving a garbage based on characteristic that not mixed. Collection system done with gathering trash from garbage bins to dump truck and determined alternative routes garbage collection. Made 3 alternative routes garbage bins back and route steady be on a route 1. Gabage bins in front of 2 alternative route chosen route 2 as steady route. Transportation system done determination of an effective and efficient by using software Arcgis 10.1. Transportation system planned made a gap in the dump trucks between organic waste and inorganic and made 3 alternative route from market to landfill Bekotok. So chosen route 1 as the route effective and efficient.Keywords: Collection, Containers, Market, Sorting, Transportation.


2020 ◽  
Vol 362 ◽  
pp. 507-516 ◽  
Author(s):  
Qiang Xu ◽  
Haozu Zhou ◽  
Yongshuai Zhu ◽  
Yeqi Cao ◽  
Bo Huang ◽  
...  

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