Designing a decoupled spherical parallel mechanism based on curved flexures: The development of a remote center of motion mechanism based on curved flexures and introducing a novel quantitative assessment method for rotary axis drift

Compliant mechanisms and decoupled parallel mechanisms are topics of high interest. The combination has been manifested for lower-mobility mechanisms, yet not attempted for higher degrees of freedom. The scarcity is countered by designing a decoupled compliant spherical parallel mechanism (DCSPM), having three independent rotational degrees of...

Extreme convective gusts in a future warmer climate assessed through a convection permitting model

Severe wind gusts associated with mid-latitude convective storms contribute to an increasing amount of natural hazard related losses in Europe. Modifications of the atmosphere associated with anthropogenic climate change are projected to increase the frequency of favorable conditions for convective storms, and it is absolutely critical to...

Outsourcing maintenance using PBMC: Introducing a decision-support method for performance based maintenance contracts

When it comes down to building or maintaining civil infrastructure commissioned by a governmental body, a lot has changed during the last couple of years. The government made a turn from all determining body, to a cooperative partner and later even to an organization that’s outsourcing most of the construction and maintenance work to second and...

Durability and performance of South African recycled granulates in unbound (sub)base pavement layers

Recycled granular materials such as Recycled Concrete Aggregate (RCA) and Recycled Crushed Masonry (RCM) are widely used in The Netherlands as base layers in asphalt pavements. The lack of natural resources and the growing amounts of demolition waste made that the Dutch industries in the early 1980s started to explore the possibilities to use...

Chloride Ingress of Carbonated Blast Furnace Slag Cement Mortars

In the Netherlands civil engineering structures, such as overpasses, bridges and tunnels are generally built using blast furnace slag cement (BFSC, CEM III/B) concrete, because of its high resistance against chloride penetration. Although the Dutch experience regarding durability performance of BFSC concrete has been remarkably good, its...

Global Ionospheric and Thermospheric Effects of the June 2015 Geomagnetic Disturbances: Multi-Instrumental Observations and Modeling

By using data from multiple instruments, we investigate ionospheric/thermospheric behavior during the period from 21 to 23 June 2015, when three interplanetary shocks (IS) of different intensities arrived at Earth. The first IS was registered at 16:45 UT on 21 June and caused ~50 nT increase in the SYM-H index. The second IS arrived at 5:45...

Probabilistic approach for the optimization of pipework inspection and maintenance

Fluctuating oil and gas prices, coupled with initiatives toward energy security, drive the global storage market of oil and gas. A tank farm, often referred to as a terminal, is an industrial facility for the storage of the oil and/or petrochemical products. Vopak's biggest terminal, Vopak Terminal Europoort (VTE), has an immense capacity of 25...

Ageing of portland cement concrete cured under moist conditions

Deterioration of microstructure in cement concrete will cause changes in the transport properties of the concrete. Transport properties at different ages of the concrete provide information about the microstructural changes of the material. A way to measure the transport properties, i.e. the chloride diffusion coefficient, in the laboratory is...

Infrastructure foundation Maintenance Management: Towards an integral optimization of the Operation and Maintenance phase.

This research deals with the general problem of existing foundation of civil infrastructure in the Netherlands that is generally not included in the maintenance management cycle. This can lead in some cases to highly undesirable situations where a lot of time and money must be spent in order to provide a safe and available infrastructure...