The Structural Behaviour and the Sheltering Efficiency of the Submerged Breakwater at the Entrance to the Port of Leixões Maintenance Charges and Effects

The urgent necessity for providing a system of protective works of the harbour of Leixoes with complementary works to improve the poor con ditions of the shelter in the basin and to protect ships entering the port became evident in 193^* In fact, the frequency of disaster to trawlers and to other ships within the basin during southwestern gales as well as the very dangerous conditions at the entrance under such gales were incompatible with the increasing economic importance of Oporto and its hinterland. These bad conditions culminated in the foundering of the 9000 T Dutch steamship "Orania" at anchor in the basin colliding on the 19th December 193^ with the steamship "Luanda" when entering the harbour under severe hurricane. The construction of the 1000 m long new breakwater was started wit a 15 m wide vertical wall to be set partly on rocky bottom and partly o a sandy bottom. Before leaving the rocky bottom the upper part of the wall was destroyed by a strong gale (Fig. l). For the advancement of t work the contractor and an official commission recommended the adoption of the Casablanca type of slope work. For economical reasons and on those of the sure possibility of its conversion into a conventional type of work, would it become convenient it was decided, at the author's suggestion, and after model study at Lausanne School of Engineer's Laboratory, to adopt a new type of submerged work, to replace the unsuccessful vertical type or the type of Casablanca proposed by the contractor (Fig. 2). The section adopted coi prised a rubble mound core of stones to 1• with the crest at level (-9m00), and berms of rubble to kF, 12 m wide to the sea side and 10 m wide to the port side (Fig. l). T The top and slopes of the mound were protected by an armour of 90 concrete blocks with the corners cut for best accommodation. The cost of the work could be reduced to half of that corresponding to the last of these types of breakwaters and its maintenance charge greatly reducec The estimated cost of the works would be reduced from JL 1.770.000 to £. 880.000 and the maintenance charges foreseen reduced from £ 35*^00 yearly to £ 2.800 yearly (comparison with the Casablanca type).

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Kajian Model Fisik Pengaruh Freeboard dan Susunan Buis Beton Sebagai Pemecah Gelombang Tenggelam Ambang Rendah (Pegar) Dalam Mereduksi Gelombang

Borneo Engineering : Jurnal Teknik Sipil ◽

10.35334/be.v1i2.600 ◽

2017 ◽

Vol 1 (2) ◽

pp. 34

Author(s):

Zulkarnain Zulkarnain ◽

Nadjadji Anwar

Keyword(s):

Low Cost ◽

Relative Depth ◽

Submerged Breakwater ◽

Wave Flume ◽

Concrete Cylinder ◽

Engineering Department ◽

Sea Area ◽

The Waves ◽

Transmission Test ◽

Better Than

The Research Center and Development of Water (Puslitbang) is currently developing the Submerged Breakwater in shallow sea area (PEGAR). The author is interested to examine the material that easily obtained in the field of RCP concrete cylinder. The observation is how it to be ability in function as submerged breakwater an go green and low cost. The physical model of wave transmission test is how the response to the structure in ability to damping of wave as the breakwater function. In this research breakwater used is submerged breakwater type by using concrete cylinder (buis beton). The purpose from this research is to know how the response of breakwater structure to the waves through it, with some variation of the structure by creating a structure with three variations of the arrangement and freeboard that is the relative depth with the crest width is constant. The wave generated test in this study is using regular waves in wave flume at FTSP Civil Engineering Department of Institute Technology Ten November. From the analysis of the effect of the installation of submerged breakwater by using concrete cylinder to the wave damping value, it can be concluded that the factors that are very influential is the freeboard and the composition of concrete cylinder. Scenario A (rigid vertical massive) is capable of producing the smallest value of kt is 0.33. As for scenario B (rigid horyzontal massive) with a damping value of 0.5, while the scenario C (rigid permeable) is only able to produce kt value of 0.71. Scenario A is better than scenario B and C Because the position of arrangement of A is very good used to damp wave in small or big freeboard conditions.

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EFFECT ON HARDNESS and MICRO STRUCTURAL BEHAVIOUR OF TOOL STEEL AFTER HEAT TREATMENT PROCESS

Scholarly Research Journal for Humanity Science & English Language ◽

10.21922/srjhsel.v4i24.10426 ◽

2017 ◽

Vol 4 (24) ◽

Author(s):

Karanbir Singh ◽

Aditya Chhabra ◽

Vaibhav Kapoor ◽

Vaibhav Kapoor

Keyword(s):

Heat Treatment ◽

Empirical Study ◽

Tool Steel ◽

Treatment Process ◽

Heat Treatment Process ◽

Structural Behaviour ◽

Treatment Processes ◽

En 31

This study is conducted to analyze the effect on the Hardness and Micro Structural Behaviour of three Sample Grades of Tool Steel i.e. EN-31, EN-8, and D3 after Heat Treatment Processes Such As Annealing, Normalizing, and Hardening and Tempering. The purpose of Selecting Tool Steel is Because Tool Steel is Mostly Used in the Manufacturing Industry.This study is based upon the empirical study which means it is derived from experiment and observation rather than theory.

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EXAMINATION OF POSSIBILITY OF SEAWEED BEDS FORMATION ON THE SUBMERGED BREAKWATER IN THE VICINITY THE SHIMANE NUCLEAR POWER STATION

Journal of Japan Society of Civil Engineers Ser B3 (Ocean Engineering) ◽

10.2208/jscejoe.67.i_292 ◽

2011 ◽

Vol 67 (2) ◽

pp. I_292-I_297

Author(s):

Kazuyuki HASEGAWA ◽

Masayuki YAMAMOTO ◽

Masao MIURA

Keyword(s):

Nuclear Power Station ◽

Nuclear Power ◽

Power Station ◽

Submerged Breakwater

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Structural behaviour of PSCC slab panel under four-point bending test

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/1144/1/012039 ◽

2021 ◽

Vol 1144 (1) ◽

pp. 012039

Author(s):

M A Iman ◽

N Mohamad ◽

A A A Samad ◽

Steafenie George ◽

M A Tambichik ◽

...

Keyword(s):

Bending Test ◽

Structural Behaviour ◽

Four Point Bending ◽

Four Point Bending Test

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Spin-ice physics in cadmium cyanide

Nature Communications ◽

10.1038/s41467-021-22515-3 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Chloe S. Coates ◽

Mia Baise ◽

Adrian Schmutzler ◽

Arkadiy Simonov ◽

Joshua W. Makepeace ◽

...

Keyword(s):

Dipole Moments ◽

Interaction Strength ◽

Magnetic Interaction ◽

Energy Scale ◽

Spin Ice ◽

Structural Behaviour ◽

Geometric Frustration ◽

Cadmium Cyanide ◽

The Difference ◽

Increased Strength

AbstractSpin-ices are frustrated magnets that support a particularly rich variety of emergent physics. Typically, it is the interplay of magnetic dipole interactions, spin anisotropy, and geometric frustration on the pyrochlore lattice that drives spin-ice formation. The relevant physics occurs at temperatures commensurate with the magnetic interaction strength, which for most systems is 1–5 K. Here, we show that non-magnetic cadmium cyanide, Cd(CN)2, exhibits analogous behaviour to magnetic spin-ices, but does so on a temperature scale that is nearly two orders of magnitude greater. The electric dipole moments of cyanide ions in Cd(CN)2 assume the role of magnetic pseudospins, with the difference in energy scale reflecting the increased strength of electric vs magnetic dipolar interactions. As a result, spin-ice physics influences the structural behaviour of Cd(CN)2 even at room temperature.

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