Tytuł Data publikacji Autor
This paper presents a critical analysis of some selected codes and practical recommendations used as basic rules in the design procedures of modern marine fender systems. The first part of the discussion pertains to the existing equations used in calculating the eccentricity coefficient in the ship’s kinetic energy equation and the maximum allowable fender pitch (spacing) in a set of fenders installed along a quay wall. A new approach for the single-fender ship-to-fender contact mode during the side-berthing procedure is introduced, assuming three different special cases (i.e., the prequarter-point case, the quarter-point case, and the postquarter-point case) of the relative position of the ship’s hull with respect to the compressed fender unit. New equations are proposed for the maximum allowable fender pitch and the extreme berthing angles associated with the postquarter-point case of the single-fender and two-fender contact modes. Taking a ferry contact with an MV-type (or pi-type) modular fender as an example, a detailed computational analysis has been performed, illustrating permissible geometrical ship-fender-quay configurations and their influence on the eccentricity coefficient, and, consequently, on the effective kinetic energy of a berthing ship.
2019
Waldemar Magda
Addressed here is the Particle Finite Element Method (PFEM) modelling of undrained CPTu penetration with regard to a reference analytical solution based on the Spherical Cavity Expansion Method (SCEM). Also discussed is the choice of the soil model and its parameters. The effect of cone interface friction on CPTu simulation is analyzed in a series of penetration tests using Arbitrary Lagrangian-Eulerian (ALE) and Updated Lagrangian (UL) methods. The results of the simulations are compared with the Authors’ proposal.
2019
Jakub Konkol,
Lech Bałachowski
Soil improvement by blasting charge technique is known in geotechnics as one of the efficient and inexpensive method. It can be used in preparing of underground to found road construction and buildings as well. The technique proves usefulness especially when dynamic load is applied. It is because of non-stiff or rather resilient type soil after improvement. In noncohesive or organic soil, blasting charge must be used with well-graded soil or similar granular material layered as working platform. Explosions cause exchange of soil. Using dredged-ash material mixture it can be benefitable in resource management and ecology. The purpose of research was finding a fast method of soil improvement to prepare special constructions like airstrips for landing and taking off light and small aircrafts. Expected results can be achieved after using blasting charge technique.
2019
Eligiusz Mieloszyk,
Mariusz Wyroślak
his paper presents the ‘CPT 2012’ model incorporated into the AFNOR NF P94-262:2012-07, French standard for pile design fully compatible with Eurocode 7, to the wider Polish audience. The bearing capacity of three reference columns for Vistula Marshlands have been calculated according to ‘CPT 2012’ model and AFNOR recommendations. Then, the design resistances have been compared with ultimate column bearing capacity measured during static load tests conducted on reference columns. The results of comparison are discussed and the discrepancies between measured and calculated bearing capacities are shortly commented.
2019
Lech Bałachowski,
Jakub Konkol,
Kamila Międlarz
The study addresses the question of the possible design benefits when considering the interaction between a modern marine modular rubber fender and a steel tubular pile substructure of a berthing dolphin. Absorption of the berthing kinetic energy of the vessel by a dualelasticity pile-fender berthing system is described in detail using the interactive treatment method (ITM). Application of the ITM is illustrated by a calculative example, assuming a 37,700 deadweight ton (DWT) tanker as a berthing ship, realistic geometries of large-diameter steel piles of the berthing dolphin substructure, and a family of Sumitomo Pi-type modular rubber fender units. By splitting the berthing kinetic energy into two parts absorbed by two elastic component elements of the dual-elasticity system of the berthing dolphin, the ITM is an effective tool for proper selection of the minimum required size (i.e., outside diameter and wall thickness) of steel piles of the berthing dolphin substructure in relation to the size of fender unit assumed. Finally, using ITM, an example analysis is performed to illustrate the influence of fender size selection on the berthing force, and the mass and stiffness of the steel-pile substructure of the berthing dolphin, as meaningful parameters influencing the most economical solution in the berthing dolphin design.
2019
Waldemar Magda
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