Liao B.,State Key Laboratory for GeoMechanics and Deep Underground Engineering |
Zhou G.-Q.,State Key Laboratory for GeoMechanics and Deep Underground Engineering |
Shang X.-Y.,State Key Laboratory for GeoMechanics and Deep Underground Engineering |
Qiao L.-J.,Beijing Huayu Engineering Co.
Meitan Xuebao/Journal of the China Coal Society
The new sensing technology based on sensitive conductive rubber's composites was studied for the deformation testing of geosynthetics. The rubber-composites filled with conductive filler were conductive, force sensitive, flexibility, and high elastic. Based on the composites, the new sensor was developed for the deformation testing of geotextile reinforcements which is flexible and the deformation is large. The new test technology was applied to the field measurement of reinforced soil retaining wall in a coal mine slot positions foundation. The results show that the tension of belt is proportional to the depth of soil, the maximum stress points appear in the 1/2 to 2/3 of length along the reinforced belt and the belt is safe. The new sensor provides a new method and mean for the deformation testing of reinforcement material. Source
Ran J.-C.,China University of Mining and Technology |
Li G.-S.,China University of Mining and Technology |
Cao Y.-J.,China University of Mining and Technology |
Liu C.,Beijing Huayu Engineering Co.
Meitan Xuebao/Journal of the China Coal Society
Specific nature property of mineral composition in coal fly ash is the key factor to depress froth stability of unburned carbon flotation. This study intends to improve froth stability via the addition of inorganic salt cations. Three different inorganic salt cations (Na+, Mg2+, Fe3+) were added into both solutions with only frother and flotation pulp system with ash particles. The influence of inorganic salt cations on foam and froth stability was studied systematically. The results indicate that the addition of salt cations improves the stability of gas-liquid foam and gas-liquid-solid froth. The stabilization function of Fe3+ to the foam or froth is stronger than Mg2+ and Na+. Based on the above study, the flotation of coal fly ash from Hubei province of China was conducted. Compared with flotation system with no salt cations, the LOI of low carbon product could be reduced from 8.85% to 5.57% in the flotation system with 3 mmol/L Fe3+. The unburned carbon removal rate of low carbon product is improved from 41.94% to 74.55%. Compared with flotation system with Fe3+, the function of Mg2+ and Na+ to the floatation indexes is weakened in due order. ©, 2015, Meitan Xuebao/Journal of the China Coal Society. All right reserved. Source
Song Q.-J.,CAS Wuhan Institute of Rock and Soil Mechanics |
Li H.-B.,CAS Wuhan Institute of Rock and Soil Mechanics |
Li J.-R.,CAS Wuhan Institute of Rock and Soil Mechanics |
Qu H.-Y.,Beijing Huayu Engineering Co. |
And 2 more authors.
Yantu Lixue/Rock and Soil Mechanics
Equivalent nonlinear model is usually applied in seismic response analysis. The shear modulus and damping ratio are two important properties in this model. Highly weathered granite is common in large engineering. It is essential to study dynamic properties of highly weathered granite. The shear modulus and damping ratio of highly weathered granite are studied with GDS resonant-column; as its the capability is excellent, it is popular in the world. The confining pressure and pore water pressure to consolidate can be controlled well by GDS RCA. After the end of sample' consolidation, shear modulus and damping ratio can be given by experiment in the state of this effective stress. Changing confining pressure and pore water pressure, resonant frequency, shear modulus and damping ratio can be given with another effective stress. In different effective stresses, variation of shear modulus and damping ratio can be observed. And fitting curves of shear modulus and damping ratio that are put forward by Hadin-Drnevich are turned out on the basis of experimental data. The authors discuss the damping mechanism of highly weathered granite sample by amfusing frictional theory. It can be seen that resonance frequency of the sample's system has a positive correlation with shear strain, but sample's damping ratio has a negative with shear strain. The effective stress can have impact on both sample's shear modulus and damping ratio. However, pore water pressure can only act on damping ratio. Source
Lai X.,Xian University of Science and Technology |
Zheng J.,Xian University of Science and Technology |
Zheng J.,Beijing Huayu Engineering Co. |
Jiang X.,Shenhua Xinjiang Energy Co. |
And 3 more authors.
Caikuang yu Anquan Gongcheng Xuebao/Journal of Mining and Safety Engineering
Surrounding rock of roadway here is deformed easily in fault regions. With coal excavation, concentrated stress formed before working face will cause movement or activation of faults, so that it can lead to a dynamic disaster. In response to the determination of the influential range of dynamic pressure in coal-rock fractured fault zone, taking the specific condition of No.1193 working face in Tunbao mine as the field research object. Combined with hybrid analyses, including mechanism analysis and field measurement, the stress distribution parameter inside the surrounding rock is collected through laying the stress detector and anchor bolt in the rib. It can be concluded that the scope of dynamic pressure within the stope is about 34 m, with the peak dynamic pressure occurring at 5 m before the working face. The assessment of the dynamic pressure can optimize the design of supporting reasonably and ensure the safety of the No.1193 working face in Tunbao colliery. © 2016, China University of Mining and Technology. All right reserved. Source
Zhou T.,Changan University |
Wu H.,Changan University |
Jiang L.,Baosteel |
Dong H.,Beijing Huayu Engineering Co.
Tumu Gongcheng Xuebao/China Civil Engineering Journal
An experimental study on eight full scale specimens, composed of reclaimed sandwich board, calcium silicate board is carried out under monotonic horizontal loading and cyclic horizontal loading to investigate the feasibility of sandwich board replacing the traditional wallboard in cold-formed steel composite wall. The main failure modes and failure processes of these specimens are analyzed for the performance indices including yield load, maximum load, failure load, shearing stiffness and the structural ductility factor. Experimental results show that replacing the traditional wallboard with the structure of sandwich board with supporting steel X-strap bracing is feasible, steel X-strap bracing is capable of reducing the slippage at the interface of wallboards and significantly increasing the shear capacity of the composite walls. Compared with sandwich board cold-formed steel composite wall without external calcium silicate board, the shearing stiffness and shear capacity of the wall with external calcium silicate board increase indistinctively. The shear capacity of composite wall with double boards approaches to the sum of the shear capacity of composite wall with single sandwich board and that of the wall with single calcium silicate board. Source