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In recent years, concrete block (CB) pavements have become a favourite alternative to asphalt pavements, mainly in intra-urban regions due to their architectural design possibilities. Unfortunately, this trend is restrained by a lack of adequate design methods to assess the load capacity and durability of such pavements. Especially, the mechanical performance of the vertical joints between CBs is often not depicted realistically enough. For this reason, in this work three new experiments are proposed to determine the mechanical behaviour of the joints between the CBs, and thus the load transmission capability of different joint formations. Mechanical models and the corresponding material parameters to describe the joint behaviour are identified from the experimental results. Finally, performance optimisation of block pavements with respect to their jointing behaviour should become possible. [ABSTRACT FROM AUTHOR]

In recent years, pavement structures with paving slabs have gained importance, especially in urban trafficked areas, because they provide more design options and have great potential with regard to durability and low maintenance compared to flexible pavements. In order to exploit this potential, an accurate and reliable performance prediction by means of appropriate design concepts is necessary. Contributing to this topic, a numerical simulation tool was developed and its performance evaluated by means of full-scale accelerated pavement tests (APT). Within this paper (Part I of this work), the APT using the New Mobile Load Simulator (MLS10) is presented. The APT program was carried out by the Swiss Federal Laboratories of Material Science and Technology on four test sections with concrete slabs of different dimensions. Two of them were instrumented with soil pressure cells and horizontal strain gauges in order to assess the primary response under the 65 kN wheel load. With a loading speed of 22 km/h under a super single tire, up to 38,400 load passes per day could be simulated on the test sections. With a frequency of the measuring sensors of 100 Hz, the stress peaks in the concrete slabs as well as at the top of the upper base course and the subgrade were recorded during the whole testing period. Overall, a very successful test execution has led to valuable and reliable data, which will be used to assess and validate the performance of a numerical simulation tool. [ABSTRACT FROM AUTHOR]

In recent years, pavement structures with paving slabs have gained importance, especially in urban trafficked areas, because they provide more design options and have great potential with regard to durability and low maintenance compared to flexible pavements. In order to exploit this potential, an accurate and reliable performance prediction by means of appropriate design concepts is necessary. Contributing to this topic, a numerical simulation tool was developed and its performance evaluated by means of full-scale accelerated pavement tests (APT). Within this paper (Part II of this work), a numerical simulation tool is proposed which is able to take into account the non-linear and plastic behavior between paving slabs (vertical joints) and between slabs and sandbed. The material parameters required for the paving concrete slabs, the vertical joints and the base courses are obtained by identification experiments. Finally, the main results from the APT could be reproduced very well with the numerical simulation tool without using phenomenological parameters. [ABSTRACT FROM AUTHOR]

Block pavements are an attractive alternative to asphalt and concrete pavements, especially in communal areas. Architects and urban planners would like to take advantage of various shapes, colours and textures of paving blocks in order to achieve a higher quality of urban space if the performance of block pavements could be better predicted to avoid large horizontal displacements of chipped stone corners and rutting. Unfortunately, the computational performance prediction of paving block structures is more complex than that for flexible pavements with homogeneous surface layers of asphalt concrete. The influence of the large number of vertical joints between paving blocks on the overall mechanical performance has not been considered sufficiently within computational tools yet. The proposed numerical simulation tool is able to take into account the complex mechanical behaviour of sand-filled joints as well as the non-linear mechanical behaviour of the underlying base courses. Joints are modelled using a Mohr-Coulomb-type friction model with the normal stresses non-linearly related with joint opening. Three different experimental set-ups were developed for the identification of the model parameters. The base behaviour was modelled using the Drucker-Prager cap model. The paper shows that the proposed tool predicts reasonable deformations and stresses in block pavements. The results of the simulations were compared with measured stresses from the full-scale accelerated pavement testing and a good agreement was observed. [ABSTRACT FROM AUTHOR]