Mechanical and durability assessment of concrete containing seashells: A review

<p>The infrastructure of ASFiNAG is mainly built from reinforced and prestressed concrete, which despite all regular maintenance measures, is subject to ageing and degradation. The major degradation process is chloride attack, followed by carbonation, which both lead to corrosion of the reinforcing steel. In this paper chlorides in the concrete are analysed with a new method, which represents a major improvement over previous assessment. The paper also introduces a new concept for the durability assessment by using objective indicators, like chloride content, electrical resistivity, and corrosion potential. For objectivity and a reliable determination of the condition state, an overall performance index derived from the condition indices using an analytic hierarchy process (AHP) is adopted. The model is applied to excellent and dense data from a monitoring system and investigations taken from reinforced concrete components beside the motorway.</p>

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Hygrothermal Performance and Degradation of Gypsum Houses in Different Brazilian Climates

Diffusion Foundations ◽

10.4028/www.scientific.net/df.3.137 ◽

2015 ◽

Vol 3 ◽

pp. 137-149 ◽

Cited By ~ 2

Author(s):

R.M.S.F. Almeida ◽

P. Paula ◽

A. Santos ◽

N.M.M. Ramos ◽

J.M.P.Q. Delgado ◽

...

Keyword(s):

Simulation Software ◽

International Standards ◽

Computer Simulation Model ◽

Water Absorption Coefficient ◽

Vapour Permeability ◽

Climatic Regions ◽

Hygrothermal Simulation ◽

Durability Assessment ◽

And Performance

This work consisted of two main lines of research: one of a literature review and other of simulation. In the first part, a modular constructive system based on gypsum blocks is presented. This constructive system reduces the manpower considerably, the time of execution and the final costs of construction. However, the durability assessment should be analysed but first its implementation and performance along the country must analysed.In this work a preliminary experimental characterization of the thermal conductivity, vapour permeability and water absorption coefficient of two different samples of gypsum plasters from the northeast Brazil (plaster pole of Araripe, Pernambuco) was performed. The experimental and analytical procedures followed either international standards or well-established methodologies, supporting the analysis of gypsum walls hygrothermal behaviour. The measured properties were adopted as inputs to hygrothermal simulation software and the analysis of gypsum based exterior walls was conducted for different climate zones and exposure conditions. The study demonstrates the durability issues that may arise in each location, due to differences in hygrothermal action.The other simulation part included hygrothermal advanced modelling, using the EnergyPlus software. The numerical results carried out allow a discussion over the interior comfort and durability of this modular constructive system. In this paper, the computer simulation model and the results of a parametric analysis of the dwelling performance on the eight climatic regions defined in Brazilian regulations are presented. The model was validated using the in situ measurements of air temperature.

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C163: Durability assessment of the Flex-Xc digital flexible ureteroscope

European Urology Supplements ◽

10.1016/s1569-9056(14)61544-x ◽

2014 ◽

Vol 13 (6) ◽

pp. e1343

Author(s):

R. Multescu ◽

P. Geavlete ◽

D. Soroiu ◽

D. Georgescu ◽

G. Nita ◽

...

Keyword(s):

Flexible Ureteroscope ◽

Durability Assessment

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Durability Assessment of Lightweight Cellular Concrete in Subgrade by the Method of Analytic Hierarchy Process Combined with Fuzzy Comprehensive Evaluation

Mathematical Problems in Engineering ◽

10.1155/2019/4915870 ◽

2019 ◽

Vol 2019 ◽

pp. 1-10

Author(s):

Xin Liu ◽

Chengwei Ni ◽

Liye Zhang ◽

Ke Sheng ◽

Baoning Hong

Keyword(s):

Analytic Hierarchy Process ◽

Influencing Factors ◽

Comprehensive Evaluation ◽

Fuzzy Comprehensive Evaluation ◽

Assessment Method ◽

Assessment Model ◽

Analytic Hierarchy ◽

Durability Assessment ◽

Hierarchy Process ◽

Cellular Concrete

The durability of lightweight cellular concrete (LCC) and the corresponding assessment method are studied in this paper to improve the utilization of LCC in subgrade construction engineering. The durability assessment method is established by combining the analytic hierarchy process (AHP) with fuzzy comprehensive evaluation (FCE). The main assessment processes are as follows. Firstly, based on the physical and mechanical properties of LCC, the influencing factors are selected in terms of preliminary design, construction technology, and operation and management after completion of construction. The grading standard of influencing factors is established as well. Secondly, a multilevel assessment model with targets level, criteria level, and indexes level is established. AHP determines the effective weight of the lower level relative to the upper level. The consistency check of the judgment matrix is conducted to prove the rationality of the distribution of influencing factors’ effect weight. Thirdly, the membership function which is suitable for each influencing factor is built to calculate the membership degree. Besides, the practicality and reliability of AHP combined with FCE are demonstrated through a practical engineering case, which is the third section of a highway in Guangdong Province, China.

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