THE IMPACT OF WHOLE-LIFE COSTING ON THE DURABILITY DESIGN OF CONCRETE BRIDGES.

Purpose – The main purpose of the study is to promote consideration of the issues and approaches available for costing sustainable buildings with a view to minimising cost overruns, occasioned by conservative whole-life cost estimates. The paper primarily looks at the impact of adopting continuity in whole-life cost models for zero carbon houses. Design/methodology/approach – The study embraces a mathematically based risk procedure based on the binomial theorem for analysing the cost implication of the Lighthouse zero-carbon house project. A practical application of the continuous whole-life cost model is developed and results are compared with existing whole-life cost techniques using finite element methods and Monte Carlo analysis. Findings – With standard whole-life costing, discounted present-value analysis tends to underestimate the cost of a project. Adopting continuity in whole-life cost models presents a clearer picture and profile of the economic realities and decision-choices confronting clients and policy-makers. It also expands the informative scope on the costs of zero-carbon housing projects. Research limitations/implications – A primary limitation in this work is its focus on just one property type as the unit of analysis. This research is also limited in its consideration of initial and running cost categories only. The capital cost figures for the Lighthouse are indicative rather than definitive. Practical implications – The continuous whole-life cost technique is a novel and innovative approach in financial appraisal […] Benefits of an improved costing framework will be far-reaching in establishing effective policies aimed at client acceptance and optimally performing supply chain networks. Originality/value – The continuous whole-life costing pioneers an experimental departure from the stereo-typical discounting mechanism in standard whole-life costing procedures.

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Research on Disease Analysis and Maintaining Technology of Bridges for Middle and Short Span in Nantong

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1065-1069.956 ◽

2014 ◽

Vol 1065-1069 ◽

pp. 956-961

Author(s):

Ning Chen ◽

Zhi Hua Ma ◽

Ping Bai ◽

Qiu Yang Liu

Keyword(s):

Statistical Analysis ◽

Strong Correlation ◽

Structure Type ◽

Concrete Bridges ◽

Main Structure ◽

The Common ◽

Short Span ◽

The Impact ◽

Disease Analysis

Under the impact of environment, climate, conservation conditions and other factors, forms of bridge disease vary in different areas. This paper has researched on concrete bridges for middle and short span in Nantong. Through the investigation of bridges disease in Nantong and statistical analysis of the main structure type and related diseases, what can be seen is that the bridge diseases have a strong correlation with the region.Considering the characteristics in this area, by analyzing the common damage of bridges of different forms, the maintaining methods which are suitable for different forms have been put forward.

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Investigation on the Index System for Durability of Concrete Bridges in Codes

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.94-96.1577 ◽

2011 ◽

Vol 94-96 ◽

pp. 1577-1582

Author(s):

Yu Qian Wang ◽

Shou Shan Cheng ◽

Wan Heng Li ◽

Yi Li

Keyword(s):

Index System ◽

Environmental Effect ◽

Concrete Bridges ◽

Durability Design ◽

Durability Index ◽

The Index System ◽

Design Construction ◽

Durability Of Concrete ◽

Three Phases

This article surveys and studies the design, construction and verification codes related to durability of concrete bridges both home and abroad, contrastively analyzes their requirements on environmental effect, durability design, construction and testing indices, and finally brings up the durability index system suitable for Chinese concrete bridges which covers the four hierarchies of environment, material, components and structure, and also considers the three phases of design, construction and verification.

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A Study of Convergence to Control the Cost of Concrete Bridges in the Design Stages in Yemen

Civil Engineering Journal ◽

10.28991/cej-0309114 ◽

2018 ◽

Vol 4 (3) ◽

pp. 539

Author(s):

Majed Al-Sebaeai ◽

Khalil Mohammed Al-Bukhaiti ◽

Shixiong Zheng

Keyword(s):

Cost Control ◽

Software Tool ◽

Concrete Bridges ◽

Design Phase ◽

The Road ◽

Database Structure ◽

The Republic ◽

The Cost ◽

Technical Solutions ◽

The Impact

This research deals with the subject of concrete bridges projects cost control during the design phase. This research falls within the framework of the road bridges projects where cost control is used as a tool to help design and decision making.The objective of this study is to develop a methodology to control the cost of bridge projects during the early design stages, by investing the database with any helpful software tool, the proposed cost control methodology is based on modeling the original elements and proposing a method of cost estimate based on the estimate of quantities from general parameters of origin and prices be updated periodically. The proposed methodology studies the various technical solutions chosen by the designer and evaluates them economically.In this paper, a study was conducted on (12) bridges within the capital Sana’a bridges project and (7 bridges) those carried out in Sana’a-Aden road, by using the statistical program (SPSS) as a specialized program in this field, logical and theoretical issues have also been taken into account. Results that require us to study the design of the bridges based on a controlled database and applied to the case of cost and time, and on the impact of implementation risk on the cost of the project during the design phase, and the various models necessary to design a database structure that was enriched with information collected from different bridge projects were presented in the Republic of Yemen.

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Research on Simplifying the Buffeting Response Spectrum of Suspension Bridge

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.791-793.370 ◽

2013 ◽

Vol 791-793 ◽

pp. 370-373

Author(s):

Hua Bai ◽

Yue Zhang

Keyword(s):

Response Spectrum ◽

Damping Ratio ◽

Suspension Bridge ◽

Concrete Bridges ◽

Main Beam ◽

Response Analysis ◽

Long Span Bridges ◽

Buffeting Response ◽

Long Span ◽

The Impact

In order to solve the problem of traditional buffeting analysis method is complex, the paper summarizes a calculation method of simplifying the suspension bridge buffeting response spectrum which considers the background response by simplifying the vibration mode function. Examples calculation shows that this function is efficient and accurate. With this method the paper analyzes the impact of parameters including structural damping ratio, aerodynamic admittance function, pneumatic self-excited forces, the main beam span and so on on the suspension bridge buffeting response. Results show that: First, the impact of the background response on concrete bridges with larger damping ratio cannot be ignored. Second, when aerodynamic admittance takes Sears function, the buffeting response analysis results may be partial dangerous. Third, the role of the background response on large long-span bridges of more than 2000 m can be ignored.

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The Effect of Shape on Chloride Penetration of Circular Reinforcement Concrete Columns and Its Durability Design

Applied Sciences ◽

10.3390/app10020459 ◽

2020 ◽

Vol 10 (2) ◽

pp. 459

Author(s):

Gu Yin ◽

Li Pan

Keyword(s):

Diffusion Model ◽

Chloride Diffusion ◽

Model Parameters ◽

Geometrical Shape ◽

Initiation Time ◽

Minimum Thickness ◽

Corrosion Initiation ◽

Durability Design ◽

Corrosion Initiation Time ◽

The Impact

The reinforced concrete (RC) circular element is usually simplified as slab one on the issue of chloride diffusion simulation, without considering the effect of the geometrical shape. In the paper, a modified slab diffusion model is proposed for circular section. A formulation for estimating the error caused by neglecting the effect of shape on chloride diffusion is derived. The formulation demonstrates that radius significantly affect the error. When shape is neglected, the effects of model parameters, including the diffusion coefficient, radius, cover concrete thickness and age factor, on the corrosion initiation time are investigated. The result shows the radius has a slight effect on calculating the corrosion initiation time compared with other model parameters. Furthermore, the influence of shape on estimating on reliability index for different service time is also discussed. A guideline is proposed for properly using the modified slab diffusion model instead of the original one to predict service life. Finally, the impact of the shape of the RC circular column on the durability design against chloride corrosion is studied. The design result when the column is simplified as a slab element indicates a lower required minimum concrete cover thickness. The minimum thickness should be improved by 5 mm as a conservative choice based on the result of the slab element.

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Effect of polycarboxylate and polyarylate surfactants on corrosion of the steel reinforcement embedded in the concrete

MATEC Web of Conferences ◽

10.1051/matecconf/201825101026 ◽

2018 ◽

Vol 251 ◽

pp. 01026 ◽

Cited By ~ 1

Author(s):

Linar Talipov ◽

Evgeny Velichko

Keyword(s):

Reinforced Concrete ◽

The United States ◽

Steel Reinforcement ◽

Concrete Bridges ◽

Passive State ◽

Chemical Additives ◽

Polymeric Surfactants ◽

Global Cost ◽

Chlorine Ions ◽

The Impact

We considered the possibility to inhibit the corrosion of the steel reinforcement embedded in the concrete using different polymeric surfactants, when paired with the passivating and plasticizing chemical additives. Previously [1] the authors proposed the method to form the protective films on the surface of the steel reinforcement embedded in concrete using the polycomponent anticorrosion naphthalene sulfonate superplasticizer based additives. The results of further surveys provided in this article proved, that under the special conditions the polyarylate and polycarboxylate surfactants are capable to keep the steel reinforcement in the passive state in presence of chlorine ions. This is especially relevant, considering the fact, that the polymer additives intended for plasticization of concrete are more widely used for the manufacturing of the monolithic and prefabricated reinforced concrete structures. In the same time Deicing agents having in its composition chlorine ions, are widely used for deicing of roads in different countries. Chlorine ions adversely affect the reinforcement of concrete artificial structures in transport. the corrosion of metals incurs huge losses, the global cost is $ 2.5 trillion, equivalent to 3.4% of world gross domestic product (GDP) for 2013[2]. In 1993, the United States spent 20 billion dollars on the repair of reinforced concrete bridges only because of the impact of chlorides[3].

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Concrete Bridge Durability Design and Maintenance

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.147.55 ◽

2011 ◽

Vol 147 ◽

pp. 55-61

Author(s):

Hao Tian ◽

Guo Ping Li ◽

Ai Rong Chen

Keyword(s):

Service Life ◽

Environmental Parameters ◽

Degradation Process ◽

Research Direction ◽

Assessment Method ◽

Concrete Bridges ◽

Concrete Bridge ◽

Durability Design ◽

Design Service Life ◽

Critical Problems

The fundamental approach for solving the durability deficiency is to perform the durability design for planned concrete bridges and the durability maintenance for existing concrete bridges. Most of the existing durability design and maintenance methods, however, are qualitative and contain many subjective factors, which cannot solve the problems such as whether the structure is safe or not throughout the service life. The critical problems, such as the design service life, the environmental parameters, the material degradation process, as well as the lifetime performance assessment method, are found out based on deep insight into the existing concrete bridge durability design and maintenance methods. Finally, the schematics of concrete bridge durability design and maintenance methods that can quantitatively evaluate the degradation process of concrete bridges are proposed and the further research direction is determined.

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