Applied Mechanics and Materials Vol. 525

Abstract: In this paper, an experimental investigation was carried out to examine the influence of hooked end steel fiber volume fraction and curing conditions on the compressive performance of concrete produced by using ordinary portland cement (OPC) and alkali-activated slag (AAS). Three different volume fractions of 0.5%, 1.0% and 1.5% were used in OPC and AAS concrete mixtures. Cylindrical specimens with 100 x 200mm were tested for compressive behavior of both concretes at 3, 7 and 28 days of curing age. Test results showed that curing conditions had a significant effect on compressive properties in the hardened OPC and AAS concretes. The addition of steel fibers generated a decrease in compressive strength of OPC while an increase in the compressive strength of AAS concrete was shown with adding steel fiber.

Abstract: Use the established multi-objective optimization model to optimize the benchmark building scheme. By comparing the analysis of the benchmark buildings efficient optimization, the established multi-objective optimization model in this paper has higher accuracy and stability, and can be used to guide the scheme design of engineering designer.

Abstract: Monitoring the condition of steel corrosion in reinforced concrete (RC) is imperative for ensuring structural serviceability and durability of RC structures. The techniques based on ultrasonic guided wave (UGW) gain more and more popularities as they have many advantages for monitoring corrosion in reinforced concrete. In this paper, UGW based monitoring techniques in the past decade are reviewed, including corrosion monitoring mechanism and feature extraction, monitoring corrosion induced deboning, monitoring pitting corrosion, monitoring corrosion induced interface roughness. Finally, the challenges and future trends in the development of UGW based monitoring techniques for condition assessment of corrosion inreinforced concrete are put forward in this paper.

Abstract: As the premier construction material across the world, concrete has a major determining role on the effects, good or bad, of construction on the environment, meanwhile the formwork system is one of the important construction methods in building construction, which eventually will lead to more sustainable construction. This study is about the sustainability elements that respond to formwork system and their contribution to the main factors of sustainability using questionnaire survey distributed among construction experts. The economic factor had the most contribution to sustainability performance of formwork system; the environmental factors come second and at final come the social factors. Furthermore, the economic factor had seven elements effect formwork system performance and the environmental factor include six elements while social factor had only three elements.

Abstract: Environmental aspect is one of the important criteria that define and determine sustainability performance for concrete formwork system. This study is aimed to compare the performance of the most common types of formwork system Conventional Formwork & Steel Formwork System in responding to environment category of sustainability development using questionnaire survey distributed among construction experts. The steel formwork system gets 11.5 score points while conventional formwork collects 7.8 points of total 19.4 score can be achieved. Overall steel formwork performance surpasses the conventional formwork while their score for formwork reusable element was adjacent with only 0.5 score difference meantime steel formwork had override conventional formwork in impact on local environment element. Generally steel formwork system may conceder as more environment friendly than conventional formwork especially in waste generation and using renewable material.

Abstract: Hong Kong-Zhuhai-Macao Bridge, the main structure is immersed tube tunnel bridge, its design life of 120 years, to find a suitable detection method is essential to assess the durability of the tunnel to ensure quality. TORRENT detection method and concrete testing radar combining such a large cross-section of the tunnel concrete structures nondestructive testing, test results show that the combination of these two methods on its own merits, the principle can efficiently detect large section structure permeability. NDT permeability through the tunnel to achieve effective assessment of the quality of concrete.

Abstract: A new rectangular anti-icing structure with short pin fins is presented in this paper. Detailed experimental research is applied to discussing its heat transfer and enhancement characteristics. The results show that, heat transfer of this anti-icing structure enhances obviously, and the core factor for enhancement is the volume ratio occupied by pin fins in rectangular channel of anti-icing structure.

Abstract: The traditional remanufacturing mostly focus on the technical measures which are aimed to keep and restore the available state after products design, produce and put into use. The design work before they are put into use is less involved. The high-level product innovation design theory, for exampleTRIZ, can scientific refining innovative ideas and provide mature theoretical system and method for design problems. Reasonable use them to innovative design the remanufactured products can scientific guiding products remanufacturing process, increase the scientific nature of the decision-making program and create enormous social and economic benefits.

Abstract: Construction of buildings on soft ground, key issues need to improve the bearing capacity on soft ground. The cement mixing pile and high pressure rotary grouting pile technology are widely applied in road soft foundation consolidation engineering. However, due to the impact of various factors of construction technology, machinery and equipment, geological conditions, such as the quality of the construction team, quality control has great difficulty. This paper presents three indicators - SPT blow count, and core samples described and unconfined compressive strength of cement mixing pile quality evaluation, which SPT blow count based, core sample description, followed by anti-supplemented unconfined compressive strength. According to certain standards of each score, and assign different individual scores are weighted average weights to obtain weighted score of three indicators of the quality.

Abstract: A dynamic simulation method of thermal environment was presented to evaluate the thermal performance of solar greenhouse. Solar greenhouse was firstly simplified into several components according to characteristics of its structure and materials, and then each component was divided into several temperature elements. For each element, heat balance equation was respectively built and integrated into a lumped model which was used to describe the thermal system of solar greenhouse. Consequently, a dynamic simulation based on state-space method was developed to calculate indoor temperature variations under the ambient conditions and structures of solar greenhouse. Experimental results show the presented method can simulate the long-term changes of indoor temperature, and are beneficial to evaluate and predict the thermal performance of solar greenhouses.