scholarly journals Engineering diagnostics of shaft lining in Gubkin Mine

2020 ◽  
pp. 64-67
Author(s):  
S. V. Sergeev ◽  
◽  
E. D. Vorobiev ◽  
I. M. Ignatenko ◽  
A. V. Zinchenko ◽  
...  
Keyword(s):  
Bearing Capacity ◽  
Field Studies ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Mine Dumps ◽  
Design Values ◽  
Engineering Diagnostics ◽  
Shaft Lining ◽  
Compression Resistance

Shafts in Gubkin Mine, KMAruda have been in operation since the late 1940s. The shafts are sunk in difficult hydrogeological conditions. At the present time, due to transition to deeper levels, deeper mine dumps are required. It is necessary to reinforce shaft lining in watered rocks. During long-term service of shaft 1, due to corrosion, thickness of liner plates and horizontal ribs has decreased by 1.5–2 and 3–5 mm, respectively (two-side corrosion). As a result, the load-bearing capacity of the tubbing has lowered by 5–7%. At the same time, the actual stresses are not higher than 22 MPa, which is 10 times less than the design compression resistance of gray cast iron as per Construction Code SP 16.13330.2017. Field studies have been performed in Gubkin Mine toward improvement of operating safety of shafts during mineral mining at deeper levels. Stress state diagnostics of lining in shaft 1 shows that the lining preserves its load-bearing capacity in all types of rocks. Thus, safe operation can be continued without extra expenses connected with the lining reinforcement. The field studies in the cage shaft show that pressure on the lining in frozen rocks is 1.5–2 times higher than the design values. It is recommended to continue the studies to estimate effects of possible rock displacements on the lining during further mining.

scholarly journals CONSIDERATIONS ON THE APPLICATION OF EUROCODES 2 AND 4 FOR CONCRETE BRIDGES

2020 ◽  
Vol 7 (1) ◽  
Author(s):  
Philippe Van Bogaert
Keyword(s):  
Bearing Capacity ◽  
Concrete Bridges ◽  
Logical Relation ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Uplift Force ◽  
The Third ◽  
Definition Of ◽  
Compression Resistance ◽  
Limiting Value

The application of certain parts of Eurocodes may result in surprising conclusions. Three independent examples of code requirements are presented. A first striking example is the fatigue compression resistance of RC or PC bridge girders and the prediction of the resulting lifetime, which may be excessively low. The second issue concerns the limiting value of slenderness of concrete arches, which shows no logical relation to the load bearing capacity. An alternative for the definition of slenderness is proposed. The third item is the necessity to consider an uplift force in the design of connectors, thus excluding virtually the use of block connections. In all three cases, alternatives are being proposed, needing further research or allowing a different approach to these issues. In addition, clarification of some code recommendations may overcome misunderstanding or erroneous application.

scholarly journals Analysis and Assessment of the Usefulness of Recycled Plastic Materials for the Production of Airfield Geocell

Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3557
Author(s):  
Mariusz Wesołowski ◽  
Piotr Włodarski ◽  
Paweł Iwanowski ◽  
Agata Kowalewska
Keyword(s):  
Bearing Capacity ◽  
Optimal Solution ◽  
Field Tests ◽  
Field Studies ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Plastic Materials ◽  
Load Carrying ◽  
Long Time ◽  
Recycled Plastics

The load-bearing capacity of natural airfield pavement has a direct impact on the safety of air operations. Unfortunately, the field tests often indicate that the load-bearing capacity of natural airfield pavements is not sufficient. In this case, it is necessary to reinforce them in order to meet the requirements set out in international documents. It is important that the method of reinforcing the subsoil is fast and as noninvasively as possible. There are many methods of reinforcing the subsoil, however, they are expensive and time-demanding, which involves turning off the airport for a long time. Airfield geocells made of recycled plastics discussed in the article seem to be the optimal solution due to the quick implementation of their application by pressing into the existing natural pavement. The article presents the results of laboratory tests demonstrating that material in question is load-resistant and chemical-resistant, while field studies have confirmed that the airfield geocell made of the plastic in question improves the load carrying capacity of natural airfield pavement.

Structure Detection and Reinforcement Method Study of Jiangsong Villa in Xiangshan Temple of Longmen Scenic Spot

2011 ◽  
Vol 243-249 ◽  
pp. 5614-5617
Author(s):  
Xiao Juan Gao ◽  
Yue Hui Li
Keyword(s):  
Bearing Capacity ◽  
Tourism Development ◽  
Structural Members ◽  
Load Bearing Capacity ◽  
Natural Action ◽  
Load Bearing ◽  
Structure Detection ◽  
Scenic Spot ◽  
Cultural Relic

Jiangsong villa is the famous ancient architecture in Longmen scenic spot. The appearance and structural members of villa are damaged seriously because of long-term natural action. Load bearing capacity of the structure reduces largely and should be repaired immediately for the cultural relic protection and tourism development. According to the surrounding requirement of scenic spot, the performance of damaged members is detected and reasonable reinforcement methods are put forward in this paper.

scholarly journals Difficulties in maintaining shaft lining – testing methods and repair methods – a case study

2020 ◽  
Vol 201 ◽  
pp. 01016
Author(s):  
Zbigniew Niedbalski ◽  
Piotr Małkowski
Keyword(s):  
Bearing Capacity ◽  
Comprehensive Approach ◽  
Testing Methods ◽  
Load Bearing Capacity ◽  
Limit Values ◽  
Load Bearing ◽  
Shaft Lining ◽  
Technical Recommendations

The paper performs the standards of shaft lining inspections used in Poland. They comprised four criterions: lining homogeneity, level of its corrosion, watertightness and load bearing capacity of the lining and the limit values for every criterion were worked out. If even one of above criterion is not met the repair works have to be taken. The example of shaft investigation and technical recommendations for the lining repair is shown as well. It is proved that only a comprehensive approach to the condition of the shaft lining can allow proper assessment of its performance for the next years.

scholarly journals Study of Load Bearing Capacity of Profiled Steel Sheet Wall Subjected to Combined Bending and Vertical Compression in Electrostatic Precipitator

2014 ◽  
Vol 8 (1) ◽  
pp. 326-331 ◽  
Author(s):  
Dengfeng Wang ◽  
Yongfu Yu ◽  
Licheng Pan ◽  
Haijin Dai
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Bearing Capacity ◽  
Steel Sheet ◽  
Loading Path ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Thin Walled ◽  
Compression Resistance ◽  
Element Method

For some electrostatic precipitators, profiled steel sheets are used as casing wall which is subjected to both bending and vertical compression. By nonlinear finite element method, the influences of structural parameters on load bearing capacity of profiled steel sheet wall were investigated. For the loading path, the uniform transversal pressure was applied firstly, and then the vertical compression was applied until the wall failed. The results indicate that the vertical compression resistance of profiled sheet decreases with the transversal load or the increasing sheet span. For certain sheet shape, the vertical compression resistance of profiled sheet decreases with the wall width increasing. The vertical resistance of the profiled sheet whose tensioned flanges are connected with the side columns is more than that whose compressed flanges are connected with the side columns. When the vertical compression resistance is calculated according to the buckling evaluation method of cold-form thin-walled steel member, the value is usually less than the solution from finite element method. Consequently, the load bearing capacity based on the related method of cold-form thin-walled steel member can be taken as a reference solution for the profiled steel sheet subjected to combined bending and vertical compression.

scholarly journals INVESTIGATIONS IN THE STRENGTH OF PRESTRESSED MULTILAYERED BEAMS UNDER THE ACTION OF LONG-TERM SHEAR/MEDINIŲ IŠ ANKSTO ĮTEMPTŲJŲ DAUGIASLUOKSNIŲ SIJŲ STIPRUMAS VEIKIANT ILGALAIKĖMS SKERSINĖMS JĖGOMS

1998 ◽  
Vol 4 (2) ◽  
pp. 109-116
Author(s):  
Rimantas Čechavičius
Keyword(s):  
Bearing Capacity ◽  
Relative Strength ◽  
Short Term ◽  
Load Bearing Capacity ◽  
Plastic Deformations ◽  
Load Bearing ◽  
Micro Cracks ◽  
Sawn Timber ◽  
Relationship Of

The results of long-term experiments are presented in the paper. As a result of the experiments, invention SU 1025831 was developed under the name “The method of manufacture of a timber load-bearing element” (E 04 C 3/12, priority since July 11, 1981). The objective of the experiments performed was to check the method of increase of load bearing capacity of glulam beams under the influence of long-term shear. 14 beams were tested: nine of them were multilayered and 5 made of board-package and square-sawn timber. All the beams failed because of the action of shear forces. Two beams were tested by static short loading, the rest twelve by long-term loading. Three beams, that have not failed because of the action of long-term loading, then were tested by short-term loading. From the tests of multilayered, glulam and solid square-sawn timber beams the decrease of the relative strength wood split alongside fibres under the action of long-term shear is bigger than that given in literature in case of standard experiments. Relationship of the level of decrease of this strength with the duration of long-term loading may be calculated according to the equation (2). The influence of long-term loading on the load-bearing capacity of these beams depends on the intensity of actions: if such a load does not cause the plastic deformations in the beam, their load-bearing capacity does not decrease and vice versa—the appearance of plastic deformations and micro-cracks means the decrease of load bearing capacity of the beam under a short-term shear. A short description of invention SU 1025831 is also presented in the paper. The invention is devoted to the perfection of the former invention No 954237. The latter one suggested an increase of load-bearing capacity of glulam elements under a short-term shear. Under a long-term load, or in case of fire, when the temperature and moisture around is changing, the strength of prestressed joint of these beams may not be fully guaranteed because of the influence of inner stresses and possible micro-cracking. With the purpose to increase the strength of beams under a long-term shear the author offers additionally to install pivots (Fig 6, 3) after giving prestress and full polymerisation. This method does not only increase the load-bearing capacity of multilayered elements under a long-term shear, but also ensures a higher reliability and fire resistance of such structures.

Increased load bearing capacity of mechanically joined FRP/metal joints using a pin structured auxiliary joining element

2020 ◽  
Vol 62 (1) ◽  
pp. 55-60
Author(s):  
Per Heyser ◽  
Vadim Sartisson ◽  
Gerson Meschut ◽  
Marcel Droß ◽  
Klaus Dröder
Keyword(s):  
Bearing Capacity ◽  
Load Bearing Capacity ◽  
Load Bearing

Load-Bearing Capacity of Direct Inlay-Retained Fibre-reinforced Composite Fixed Partial Dentures with Different Cross-Sectional Pontic Design

2017 ◽  
Vol 68 (1) ◽  
pp. 94-100
Author(s):  
Oana Tanculescu ◽  
Adrian Doloca ◽  
Raluca Maria Vieriu ◽  
Florentina Mocanu ◽  
Gabriela Ifteni ◽  
...  
Keyword(s):  
Bearing Capacity ◽  
Fracture Pattern ◽  
Load Bearing Capacity ◽  
Cross Sectional ◽  
Load Bearing ◽  
Reinforced Composite ◽  
Polyethylene Fibre

The load-bearing capacity and fracture pattern of direct inlay-retained FRC FDPs with two different cross-sectional designs of the ponticwere tested. The aim of the study was to evaluate a new fibre disposition. Two types of composites, Filtek Bulk Fill Posterior Restorative and Filtek Z250 (3M/ESPE, St. Paul, MN, USA), and one braided polyethylene fibre, Construct (Kerr, USA) were used. The results of the study suggested that the new tested disposition of the fibres prevented in some extend the delamination of the composite on buccal and facial sides of the pontic and increased the load-bearing capacity of the bridges.

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