In order to investigate the influence of storage period and water content on dynamic mechanical properties of ready-mixed shrinkage-compensating concrete, the dynamic compression tests in 3 kinds of water contents(0.5...
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In order to investigate the influence of storage period and water content on dynamic mechanical properties of ready-mixed shrinkage-compensating concrete, the dynamic compression tests in 3 kinds of water contents(0.5% ,1.0% ,and 1.5%) and 4 kinds of storage periods(3 d,7 d,10 d,and 15 d) have been carried out by φ74 mm variable cross-section splitting Hopkinson pressure bar *** influence of water content and storage period on dynamic compressive strength and failure mode for ready-mixed shrinkage-compensating concrete have been *** result shows that at the same water content, the dynamic compressive strength decreases with the increase of storage *** the water content is 0.5 %, the strength loss rate are 4.3 %, 22.2 %, 33.9 % and 47.5 % for the storage period of 3 d, 7 d, 10 d and 15 *** the water content is 1.0 %, the strength loss rate are 11.1% 31.9 %, 41.6 % and 57.1% for the storage period of 3 d, 7 d, 10 d and 15 *** the storage period is the same, the dynamic compressive strength decreases with the increase of water *** the storage period is 7 d,the strength loss rate are 22.2% ,31.9% and 42.6% for the water content of 0.5% ,1.0% and 1.5%.When the storage period is 10 d, the strength loss rate are 33.9 %, 41.6 % and 51.5 % for the water content of 0.5 %, 1.0 % and 1.5 %,*** failure degree tends to be more serious with the increase of storage period at the same water content.
Tailings pond plays a very important role in the construction of mine engineering. At the same time, tailings pond also produces huge pollution to the environment. If dam break occurs, it will cause loss of people and...
Tailings pond plays a very important role in the construction of mine engineering. At the same time, tailings pond also produces huge pollution to the environment. If dam break occurs, it will cause loss of people and property. In this paper, a tailings pond management system based on RSCIC is studied, the monitoring content of the system is determined, the more innovative system and hardware are emphasized, the program flow chart of digital processing is put forward. Adopting scientific and effective means to manage the tailing dam automatically can not only strengthen the safety protection of the tailing dam, but also provide a certain theoretical basis for the construction of other digital tailings dam projects.
In this study, a pavement evaluation was carried out on a corridor that carried heavy truck traffic, connecting a harbor, a major high-way, an airport, and industries. The pavement of the corridor was distressed frequ...
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Worldwide, there is a clear imperativeness to reduce the consumption of non-renewable raw materials. The aim of the research is to obtain new ecological materials with applicability in the construction field, but also...
Worldwide, there is a clear imperativeness to reduce the consumption of non-renewable raw materials. The aim of the research is to obtain new ecological materials with applicability in the construction field, but also to efficiently manage these by-products by eliminating it completely and re-introducing it into the economic circuit. We envisaged the use of slag products as a material cementitious characteristics or as artificial aggregates, so that materials embedded in construction produce as little environmental impact as possible. After cooling, the blast furnace slag products was used in the new mortar mixes in two forms: in the form of a powder product milled from the granulated slag, and in the form of an aggregate made of non-granulated slag, sorted to the sized of 0/4 mm. Ground-granulated slag in the form of a powder below 63 μm was used as an addition to the cement mass, and the newly obtained artificial aggregate, sorted to 0/4 mm, was used in various percentages for replacing the natural aggregates in the control mix. The results show that the combined use of slag powder as an addition to the cement mass and artificial slag aggregates, regardless of the percentage of substitution of Natural aggregates in the mortar mortar mix, has led to the development of new mortar mixes with higher compaction than the control mortar. The higher filling rate due to the use of ground slag has influenced the increase of compressive strengths and freeze-thaw strengths from the repeated freeze-thaw action for new cement mortar mixes with blast furnace slag, as compared to the control mortar mix.
A robust assessment on the impact of climate change at regional atmospheric condition is crucial to ensure the sustainability of groundwater resource for tropical karst island, where water is considered relatively sca...
A robust assessment on the impact of climate change at regional atmospheric condition is crucial to ensure the sustainability of groundwater resource for tropical karst island, where water is considered relatively scarce and thus important for the community. In this study, future long-term climate projection under HadCM3 global model climate (GCM) scenarios for a period of 2020-2090 is validated and simulated, using input data of weather variables downscaled by Statistical Downscaling Model (SDSM). The simulation indicated that the climate variables, i.e. temperature and rainfall, are expected to be affected by climate change and generally vary over the period under the scenarios. The rainfall is estimated to slightly raise by 0.14% and 0.09% under H3A2a and H3B2a scenarios, respectively. Steady temperature increases by 1.89-2.16% (Tmax) and 1.05-1.59 % (Tavg) and a decrease of 0.73-0.76% were predictable for all scenarios.
This study develops a new type of eco-friendly building brick so-called unfired four-hole hollow brick (UFHB) by using a mixture of ordinary Portland cement (OPC), low-calcium fly ash (FA), and different proportions o...
This study develops a new type of eco-friendly building brick so-called unfired four-hole hollow brick (UFHB) by using a mixture of ordinary Portland cement (OPC), low-calcium fly ash (FA), and different proportions of crushed sand (CS) and river sand (RS). A hydraulic-static pressure was applied to form the brick samples. The effect of various CS-RS blends on the mechanical strength of the UFHB samples was studied. In addition, the numerical method was applied to simulate the heat transfer process through the brick wall. The obtained results show that the UFHB mixture containing a mixture of 10% RS and 90% CS as blended fine aggregate registered the highest strength value in comparison with other UFHB mixtures. Moreover, utilization of the UFHB was highly effective in term of heat insulation as compared to the conventional brick.
Based on the foundation treatment engineering of Jiangyin economic development zone in Fujian province as an example, the soft soil foundation was treated by the method of surcharge preloading combination with dynamic...
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Based on the foundation treatment engineering of Jiangyin economic development zone in Fujian province as an example, the soft soil foundation was treated by the method of surcharge preloading combination with dynamic compaction. In construction process, it includes three the in-situ test of construction phase: Before inserting plastic drainage plate, after surcharge preloading and after dynamic compaction treatment. Focusing on soil mechanics parameters, pore water pressure and the foundation bearing capacity test, and analyzes the change trend of all the soil parameters of different stage. A variety of in-situ test results show that this method can not only greatly improve the bearing capacity of foundation soil, but also provides technical support for further in-depth study of the method of reinforcement mechanism and the optimization design.
Accurate mapping of groundwater vulnerability zones based on robust groundwater model is crucial towards an appropriate development of management strategies. This study aimed at developing groundwater vulnerability zo...
Accurate mapping of groundwater vulnerability zones based on robust groundwater model is crucial towards an appropriate development of management strategies. This study aimed at developing groundwater vulnerability zones in a tropical karst area in Rote Island, Indonesia. HGZ method was employed to accommodate the limitation of subsurface data. Using reverse particle-tracking simulation, this study combined the simulation results (travel time and pathline trajectory) with the potential groundwater contamination risk to designate three vulnerability zones. In this study preventive management measures were recommended to ensure provision of safe and good quality water from Oemau Spring and to protect the spring from contamination.
Asset management is a strategic decision-making aspect of social infra-structure that ensures safety by predicting long-term conditions and maximizing effectiveness under budgetary constraints. Predicting the deterior...
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Asset management is a strategic decision-making aspect of social infra-structure that ensures safety by predicting long-term conditions and maximizing effectiveness under budgetary constraints. Predicting the deterioration of impervious walls is essential in the asset management of coastal landfill sites, particularly in the design of their maintenance and repair strategy. In this paper, a quantitative evaluation of the leakage of toxic substances in coastal landfill sites where deterioration of side impervious walls has decreased the water interception performance is reported. In addition, risk evaluation based on the asset management of the leakage is applied to determine an appropriate repair method. The strategy of repairing the walls when the concentration of the toxic substances leaking into the sea area exceeds the closure and abandonment of coastal landfill sites is demonstrated to be superior. Moreover, the strategy of repairing only the seaside side impervious wall is shown to be cost-effective.
In parameterisation step, implementing suitable calibration methods that accurately represents the actual system is crucial in developing a dependable groundwater model in data-scarce areas. In this study, the Head-Gu...
In parameterisation step, implementing suitable calibration methods that accurately represents the actual system is crucial in developing a dependable groundwater model in data-scarce areas. In this study, the Head-Guided Zonation (HGZ) method was applied to accommodate the limitation of subsurface data, such as the lack of comprehensive spatial distribution of hydraulic conductivity and specific yield values. This study demonstrated that the spatial distribution of groundwater heads can be used to assume the spatial distribution of sub-surface parameters, hence, hydraulic conductivity zones in the model domain can be established using the distribution of hydraulic gradient. We conclude that the HGZ method is practical and applicable for development of a physically-based groundwater model.
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