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A look at the challenges of building the 5th lock chamber in Brunsbüttel The new construction of the 5th lock chamber in Brunsbüttel is currently the largest hydraulic construction site in Europe and is necessary in order to be able to subsequently repair the existing large lock chambers. A benefit‐cost analysis showed the highest benefit value for the new construction between the existing large and small locks, i. e. on the lock island. The location of the construction site results in special requirements for construction operations. In general, a large number of crafts have to be coordinated, which are necessary e. g. for the concrete and steel construction of the heads, the chamber for seagoing vessels and the outer harbours. Furthermore, it has to be taken into account, that the construction site is located at the estuary of the Elbe and thus has to be prepared for storm surges. These special boundary conditions of the construction project and selected construction methods are discussed by way of example. A special focus of the article is also on the extensive concrete technology considerations for achieving durable concrete structures. In addition to minimising crack widths in massive concrete elements, other aspects such as resistance against frost and chloride attack had to be considered for developing the concrete composition. The temporarily limited availability of fly ash made this task even more complex. In order to further improve durability, controlled permeability formwork liners were used in parts of the structure with sever exposure. [ABSTRACT FROM AUTHOR]

Recent investigations concerning the productivity of the UK construction industry and its performance compared with other European and world-wide nations have reported conflicting findings. These investigations have utilized various methodologies in attempting to measure and compare productivity levels. The present investigation uses a customized method to gauge the productivity at site level of three European national construction industries, namely Germany, France and the UK. Analysis of variance is employed to compare the productivity rates used by contractors' planning engineers for a specific concreting operation. The performance of UK contractors is found to be more disparate than those of contractors in either France or Germany. Although leading UK contractors can compete with the best on the continent, there are a number of companies whose performance is far worse than any in France and Germany, due mainly to the construction methods used by UK contractors. It is concluded therefore, that a best practice recommendation for UK contractors would be for them to avoid using traditional timber formwork methods to beams, and instead adopt more productive approaches afforded using either proprietary or prefabricated systems. [ABSTRACT FROM AUTHOR]

Results of an investigation concerning preferred methods of construction formwork by contractors' planning engineers in France, Germany and the UK are presented. Findings confirm differences amongst preferred solutions in these international locations. French and German contractors tend to employ similar proprietary formwork methods, whilst the UK 'stand alone' in preferring traditional timber solutions. It is found that company size has no significant impact on the formwork system selected. Nine formwork selection factors are identified, and ranked in terms of importance for each international group of contractors. Statistically, the rankings are shown to have significant correlation for each pair of countries. 'Relative costs', 'Specification (quality) of concrete' and 'Degree of repetition', are found to be the principal formwork selection criteria. Correlation analysis reveals association between many of these selection factors. Cet article presente les resultats d'une etude sur les methodes de coffrage recommandees par des ingenieurs de planning d'entreprises de construction en France, en Allemagne et dans le Royaume-Uni. Il ressort de cette enquete qu'il existe bien des differences entre les solutions preferees dans chaque pays. En France et an Allemagne, les entreprises ont tendance a utiliser des coffrages de marque similaires alors qu'en GrandeBretagne, la preference va aux solutions classiques a base de bois d'oeuvre. Il apparait qu'il n'existe pas de lien significatif entre la taille de l'entreprise et le systeme de coffrage retenu. On compte neuf facteurs qui president au choix des coffrages; ces facteurs sont classes en termes d'importance pour chaque groupe international d'entreprises de construction. Sur le plan statistique, le classement montre qu'il existe une correlation significative pour chaque paire de pays. Le cout relatif, les specifications (qualite) de beton et le degre de repetition sont les principaux criteres de selection des coffrages. Une analyse de correlation revele qu'il existe une association entre bon nombre de ces facteurs de selection. [ABSTRACT FROM AUTHOR]