NaCl interaction during hydration as studied by NMR

With freshwater getting scares seawater, i.e., water containing NaCl, can become the only viable option for making concrete. Although a lot of research had been directed to understanding the role of water in cement hydration, not much is known about the interaction of the Na+ and Cl- with cement paste during drying. A problem is that available techniques like, i.e., XRD, SEM, and EDX, for measuring the microstructure and the methods for determining the concentration of Na+, Cl- ions in pore solutions are either indirect or invasive and moreover often destructive, which consequently may lead to inadequate interpretations. Using a specially designed Nuclear Magnetic Resonance (NMR) setup, the 1H, 23Na and 35Cl content in cementitious materials can be measured quasi-simultaneously and hence give us direct information on the interaction of the ions and the microstructure development. We have studied the influence factor, i.e., the water-cement ratio, on the microstructure development and the binding of Cl- and Na+. It was found that during the initial hydration stage more Cl- is bound in comparison to Na+ . This is reversed during the acceleration period after which there is a preference for binding of Na+ in comparison to Cl-. Increase of W/C ratio results in less binding capability of Na+ and Cl-

Controlling Urban Sprawl with Integrated Approach of Space-Transport Development Strategies

Urban sprawl phenomenon has been a huge issue since 20th century characterized by a rapid and unbalanced settlement development with transportation network particularly in a suburban area. The improvement of public transport system is a major requirement to minimize urban sprawl. Academic researchers have explained the linkage strategy between transportation network and urban planning. However, insufficient empirical verification has been made to control this phenomenon by using the integrated approach of space-transport development. This paper focuses on analyzing the improvement of public transport supply incorporated with settlement development. The improvement of public transport (PT) is designed by planning Mass Rapid Transit (MRT), Light Rapid Transit (LRT), and Bus Rapid Transit (BRT) systems. The impact of PT improvement has affected on the settlement development. Setting balance between employment and population density is designed as alternative of urban spatial strategy. These approaches are necessary in order to analyze and evaluate the many alternatives to overcome this situation. The result reveals that the requirement to integrate the space-transport development strategy in order to control the settlement development in the suburb has to be done to reduce 10% of travel time and to increase double the usage possibility to public transport mode. The strategies should be done in the further research with considering on impact assessment and the residents preferences intended to determine the preferred and strategic option for them.Transport & PlanningCivil Engineering and Geoscience

Empirical analysis of heterogeneous traffic flow

Traffic flow in many developing countries is strongly mixed comprising vehicle types, such as motorcycles, cars, (mini) buses, and trucks; furthermore, traffic flow typically exhibits free inter-lane exchanges. This phenomenon causes a complex vehicle interaction, rendering most existing traffic flow modeling approaches insufficient and requiring a new approach. New approaches to the heterogeneous non-lane-based flow have been proposed but empirical verification has been lacking. To bridge this gap, this paper presents some preliminary analyses on a data set collected from a number of road sections in the city of Surabaya, Indonesia. Video data is used to capture aspects of vehicle interaction. Using the porous flow approach, we investigate aspects related to the pore size-density distributions and class-specific critical pore sizes.Transport & PlanningCivil Engineering and Geoscience

Containing urban sprawl: An integrated improvement of space-tranport strategies to reduce air pollution emission

Diverse effective strategies have been designed to minimize the phenomenon of urban sprawl. Previous research focused on the link between spatial and transport development strategies to achieve this goal, with the intention of increasing mobility, reducing commuting time and travel costs. However, a side effect of urban sprawl is an increase of air pollution. Higher pollution levels result in higher costs for road users. To reduce these costs, improvement in public transport linked to urban development is an essential factor in limiting air pollution emission. Current research is insufficient to demonstrate the effects of urban sprawl on air pollution emission. This paper examines the extent to which an integrated approach to space-transport development strategies is able to reduce air pollution emission. The analysis includes the effect of different improvement of public transport (PT) and spatial alternatives on the load of air pollution A pro-active approach is applied for a potential viable up to 2030. By examining the alternative strategies, the intention is to reduce travel costs together with decreasing the load of air pollution emission. This research proposes the improvement of public transport (PT) by planning a combination of Mass Rapid Transit ((MRT), Light Rapid Transit, Bus rapid Transit and feeder systems. In addition, a structure of compact zones is designed as urban spatial strategy alternatives. The conclusions indicate that firstly, the improvement of PT (a combination of Mass Rapid Transit (MRT), Light Rapid Transit, Bus rapid Transit and feeder systems) has an effect on the reduction of air pollution load compared to the current PT situation (minibuses and buses). Secondly, the spatial planning with compact zone does not show a significant decrease in determining the load of air pollution. Its substantially reduction is achieved with the design of improvement of PT systems. The best option for reducing commuting costs and air pollution, the implementation of the improvement of PT systems alternative, is then recommended.Transport and PlanningCivil Engineering and Geoscience

Composition of mortar as a function of distance to the brick-mortar interface: A study on the formation of cured mortar structure in masonry using NMR, PFM and XRD

The formation of cured mortar structure in masonry was studied using multiple experimental techniques. Starting with fresh mortar, nuclear magnetic resonance (NMR) was used to measure the water extraction during brick laying. After curing, the composition of cured mortar was investigated with polarizing and fluorescent microscopy (PFM) and X-Ray diffraction (XRD). Two typical mortars were investigated: a cement-lime mortar and a cement mortar with air entraining agent. The measurements indicate that the mortar composition (i.e. the contents of sand, cured binder and voids) and the contents of chemical substances of the cured binder (i.e. the contents of calcite and portlandite) change with distance to the brick-mortar interface. For the cement mortar with air entraining agent, the observations are explained by the enrichment of binder towards the brick-mortar interface, resulting from the local compaction and compression of the fresh mortar. In the cement-lime mortar such an enrichment of binder hardly occurs and the observations are explained by the intense carbonation that takes place. As a result, the chemical composition of the binders is very much different in both mortars. In the cement mortar with air entraining agent, near the brick-mortar interface the enrichment of cement and the low water content (resulting from the low water retentivity of this mortar), lower the water-to-cement ratio and as a consequence the cement is not fully hydrated. In the cement-lime mortar, because the Ca(OH)2 content and the water content is higher, near the brickmortar interface, a carbonated zone is formed which is hardly permeable for CO2 (and probably water). The latter does not occur in the cement mortar, it remains permeable. The analysis of the experimental results have lead to the formulation of a conceptual model for the formation of cured mortar structure in masonry. Such a model may be helpful in analysing and predicting the durability of mortars.Applied Science

Salt transport in plaster/substrate layers

Architectur

Relating sequence properties to protein secretion

Aspergillus niger is widely used for industrial enzyme production. Knowledge on high-level protein secretion could be useful to improve production rates. We used sequencebased classification methods to identify important propertiesfor successful high-level secretion, which will be used to redesign proteins for improved secretion.Pattern Recognition and Bioinformatic

Parking Spoorzone Delft: Addressing expected parking challenges 2015-2017

This project is carried out on request of the BVOW, the interest group of the neighbourhoods Olofsbuurt and Westerkwartier in Delft, in order to propose solutions for the parking issue of Spoorzone Delft expected between 2015 and 2017. They are worried that parking disturbances will emerge in their neighbourhoods when the parking places of Spoorzone Delft will be removed. Indeed, in 2015 the parking places that are currently situated below the viaduct will disappear due to the removal of the viaduct and will be replaced in 2017 by an underground parking. Thus, between 2015 and 2017 a shortage in parking places might occur. In addition, the current parking capacity of the nearby neighbourhoods Olofsbuurt-Westerkwartier cannot compensate the temporal loss of parking places, as it already now regularly suffers from a lack of parking capacity itself. The goal of this report is to find solutions in order to prevent or solve this parking problem and to provide an answer to the main research question: “How can the expected parking problems, due to construction works in the Spoorzone Delft, be prevented and/or solved in a feasible way, concerning technical, socio-political, and economic aspects?” The Spoorzone Project is explained in order to better understand the background of the problem. The actors that are involved in the removal of the parking places are the contractors that are directly involved in the construction of the project Spoorzone Delft, the users of the parking places and other actors such as the municipality, the BVOW and the shops located in parking area C (neighbourhood Olofsbuurt-Westerkwartier). Criteria based on a requirements analysis are made and an evaluation of in total 54 means is presented, generated from ideas submitted by respondents of a survey and actors interviewed, as from ideas coming from a brainstorm session. A means-end diagram is presented, after which finally in which 12 solutions for addressing the parking challenges in the Spoorzone are constructed.Transport, Infrastructure & LogisticsMechanical, Maritime and Materials Engineerin