Papers by Keyword: Soundness

Abstract: Extending the range of finished product sizes from a given ingot or concast bloom or billet section is often limited by the minimum area reduction required to ensure effective central consolidation and final mechanical properties. Predicting effective consolidation or level of remnant porosity for a range of steel grade, billet size, pass schedule/roll design and thermo-mechanical conditions has always been an important issue on plant, much more lately in view of recent trends for larger ingots and development of combined forging/rolling strategies. This paper will focus primarily on a fast analytical technique based on roll gap shape and consolidation factors obtained from Finite Element (FEM) Models. New developments based on FEM submodelling are presented briefly. Healing capabilities based on diffusion bonding can be obtained from [1-3].

Abstract: A modalized propositional Belnap-Dunn logic will be proposed in this paper which thereare four modalities [t]; [T]; [⊥]; [f] to represent the four values t;T;⊥; f; respectively, and a Gentzentypeddeduction system will be given so that the the system is sound and complete with the four-valuedsemantics of the Belnap-Dunn logic.

Abstract: In order to explore the possibility of using repeatedly recycling waste concrete as aggregate to produce structural concrete, experimental research was carried out on the structural properties of three kinds of recycled fine aggregate (RFA) with two-regeneration cycles, two single and one mixed. The results showed that the quality of all RFAs meet the needs of Grade Ⅲ in GB/T25177-2010 and Level L in JISA 5023-2000. The degree of performance degradation is observed to enhance with increasing recycling cycle when taking the same preparation process of recycled aggregate.

Abstract: The effect of MgO on performance of belite-barium calcium sulphoaluminate cement (B-CBAS) was investigated through orthogonal tests. The results show that the formation of C₃S can be improved at low temperatures by mixing MgO. SO₃ decreasing the viscosity of fused mass in sintering process was beneficial to solid solution of MgO in B-CBAS clinker. The solid solubility of MgO in B-CBAS was higher than that of Portland cement, which indicated that high-magnesium limestone can be used in B-CBAS. Even MgO content reached 5.14%, the soundness of B-CBAS was still in safe, whose compressive strength at 3d and 28d curing age were 49.1MPa and 81.9MPa. This indicated that this kind of cement has good mechanical properties.

Abstract: As-cast 30Cr2Ni4MoV steel was researched quantificationally to obtain the distribution and pattern of the microcosmic defect. By means of finite element simulation and experiment research, porosity consolidating and relative density evolution of as-cast 30Cr2Ni4MoV steel were investigated for a FM stretching process at a constant strain rate 0.001s-1. The studied parameters included three temperatures (800°C, 1000°C, 1250°C) and three deforming passes(1,2,3) and three friction factors(0.3,0.5,0.7), which bracketed the parameters that were used during most primary break-down processes. Temperature had an obvious effect on the porosity consolidating, but friction factor had no effect on the ultimate soundness nearly. When beginning temperature was 1250°C and heat exchanged considered, initial porosity can be eliminated after the accumulated effective strain reached 1.0 at least. The residual defect of the wrought material at different strain lever was compared to the initial defect of as-cast material and found to be somewhat reduced. The impact toughness of the wrought material at different strain lever was also compared to the as-cast material and found to be obvious improved. The difference in these behaviors between as-cast and wrought material could be attributed to the healing of the porosity defect and the enhancement of the soundness at a certain extent.

Abstract: To reduce the cost and improve concrete performance, massive admixtures were needed to be added to the concrete. With the research going, the high quality mixture is increasingly becoming the indispensable concrete component. The steel slag powder is the steel-slag comprehensive utilization technical commanding point compared with the level of the steel slag application nowadays in the world. In order to develop the application of the steel slag fine powder in cement concrete domain, this article analyzes autoclaved soundness of the Baosteel steel-slag fine powder as well as the compatibility of it with the cement and the concrete admixtures.

Abstract: Material composition, mix proportion and physical properties of a low carbon cement with 90% of industrial refuse, properties of the cement was measured according to chinese national standard GB1346-2001 and GB175-2008. It is seen that the cement had good soundness, long setting time, low water requirement for standard consistency, good initial fluidity and high final strength as well, the properties are beneficial for the construction of highway engineering, underwater engineering and large volume concrete engineering.