On the Issue of Designing a System for Continuous Control of Road Materials Compaction for Pavers

The results of the research on the creation of an automatic compaction control system (ACCS) for pavers in real time are considered. The research is based on the methods of artificial neural networks (ANN). In this paper, an ANN model is obtained, with the help of which it is possible to determine the compaction coefficient (CC) of an asphalt mixture. The input variables of the ACCS are the velocity of movement of the paver, the frequency of impacts of the tamper, the force in the pusher of the tamper, the type of mixture, the thickness of the layer. The results of a computational experiment on the calculation of Cc in real time are presented. The ANN is able to explain more than 98 % of the measured data.

СRUSHED STONE MATERIALS AND GRAVEL MATERIALS BOUND BY MINERAL BINDERS. STANDARDIZATION

Introduction. This paper presents the results of the standardization of requirements for granular mixtures bound by mineral binders for bases, sub-bases and top layers of road pavements used as framework for national standard «Crushed stone materials and gravel materials for the road building industry — Specifications. Part 3: The materials bound by mineral binders». Standardization. The standard covers the requirements for crushed stone-sand and sand-gravel mixtures treated with mineral binders and derived from them hardened materials as well as the requirements for source constituents. Mineral binder for the standardized type of road materials shall be selected from following main constituents: cement, slag or fly ash each separately or combinations thereof using an activator if required. Standard mixtures shall be produced in a factory or mixed in situ on the road surface. Clauses of the standard also comprise the requirements for mixtures and related hardened materials from active slag or ash-slag materials which can act as the main constituent of the mixture (aggregate) and part of the binder. Standardized mandatory characteristics include mixtures physical properties comprising grading envelopes, and mechanical properties; the obligatory sections of the standard include requirements on quality control, transporting and marking of mixtures. Conclusions. Conclusions outline main results of standardization in view of the ongoing works on processing the related European Norms as national normative documents. It is emphasized that the developed standard supplements the fundamental requirements of adapted European normative documents regarding the composition and properties of said mixtures, particularly the requirements on frost resistance. The subsequent work shall be aimed at the adaptation of national regulations on road pavement design and construction to implement the newly standardized requirements for hydraulically bound mixtures.

Analysis of Heat Absorption and Collection Based on Solid Structures Collector

A solid structure, such as a road, building wall or envelop, used as a solar collector is considered an effective and new way to use renewable energy. This paper focused on the temperature characteristics of four structures exposed to sunshine: asphalt, red brick, composite cement and concrete road slab. Furthermore, the collected heat based on a hydraulic system was investigated experimentally. For the four structure slabs, their temperature differences are due to solar radiation absorption varied greatly by the material’s heat absorptance and color. Through the test, asphalt slab attained the highest temperature and had the weakest reflection among the structures. Compared with the others, the temperature of the asphalt slab was greater by 8.1%, 14.9% and 16.4% than the brick, composite cement and concrete, respectively. The reflection intensity growth ratio was defined and indicates the growth potential for absorbing radiation in the solid slab surface. From the experiments, it was concluded that a suitable selection of road materials can greatly improve the thermal absorption, conduction and penetration into the solid slab. The collected heat capability was approximately 250 W/m2 to 350 W/m2 in the natural summer condition. A black coating or a surface modification can collect more heat, reaching greater than 250 W/m2. The solar collecting heat efficiency with a surface configuration of the road slab can reach above 30% in the summer time.

Utilization of glass waste in vehicle restraint systems

The growing demand of society requires that engineers should concentrate more and more on recycling of broken road materials and various by-products in order to ensure environmental sustainability for future generations. Concrete technology has evolved to such an extent that it has become an important role in waste/secondary material management by now. There are several benefits of using glass waste in concrete mixtures. The experi-ments carried out at the Hungarian firm Ferrobeton Ltd. concentrated on exploring the possibility of using glass waste in the cement concrete recipe of vehicle restraint systems in order to release reflection in its material and thereby to increase road safety. In the concrete recipe, the maximization of both usability and reflectivity were aimed to. However, it was also necessary to make sure that the resistance to mechanical and environmental loads could not be worse than in the case of reference (basic) mixture recipe. The quality and type of concrete surface finishing is a financial and also lifetime design issue. The surface treatment method actually applied basically influence the light properties (gleam, reflectivity) of concrete surface as a significant traffic safety parameter.

Health-oriented optimization strategies of coastal fitness environment in Qingdao

Under the initiative of “co-construction and sharing, health for all”, the natural condition of coastal area in Qingdao becomes the key area of the national fitness. Based on the health-oriented theory, authors analyze the health-oriented connotation of the coastal fitness environment, and suggest that the realization of health-oriented coastal fitness environment needs to meet the spatial demand of health-oriented behaviors and health behaviors. These behaviors should maintain accessibility and friendliness. Based on the present status survey and IPA analysis, it is concluded that the continuity and gradual changes are in urgent need of improvement, followed by smoothness, then convenience and recognizability need to update. Therefore, in combination with the acceptable time and distance, authors put forward specific optimization strategies from four aspects. That is, coastal fitness environment in Qingdao can be improved by network of coastal footpaths, intelligent management of color lightings, reasonable connecting of road materials and humanized and recognizable fitness site, in order to promote residents’ health activities and national fitness.