An anchor bearing plate transfers the anchoring force from anchor plate to the concrete and the pre-stress is formed in the concrete structure. Currently, the main type of anchor bearing plate is cast iron. It is brit...An anchor bearing plate transfers the anchoring force from anchor plate to the concrete and the pre-stress is formed in the concrete structure. Currently, the main type of anchor bearing plate is cast iron. It is brittle during transportation and tension process. This paper presents a new type of anchor bearing plate combined stamping with welding forming. The structure of the new type anchor bearing plate is introduced. The stress states of the anchor bearing plate and anchorage zone under work are studied. Various specifications of anchor bearing plate are studied by ANSYS finite element analysis software following the AASHTO specification. The analysis results are compared with the results of the same type of OVM round-shaped anchor plate. The study results show that the new pre-stressed anchor plates combined stamping with welding forming are feasible and more sturdy which can meet the engineering demand.展开更多
During the construction of some large-scale rock engineering,high-steep slopes and insufficient slope stability induced by unloading fissures are often encountered.For the reinforcement of these slopes,some techniques...During the construction of some large-scale rock engineering,high-steep slopes and insufficient slope stability induced by unloading fissures are often encountered.For the reinforcement of these slopes,some techniques(including conventional pre-stressed anchoring cable and unconventional anchoring hole)are usually utilized,however,having several obvious defects.Thus,it is very difficult for a designer to design an efficient reinforcement scheme for the high-steep slopes.For this reason,the authors develop the pre-stressed anchoring beam technique,in which tensile capacity of pre-stressed structures are fully utilized.It is analyzed that the new technique is characterized by multi-functions,including engineering investigation,efficient reinforcement,drainage,monitoring and urgent strength supplement,and hoped to be extensively applicable in the reinforcement of high-steep slopes.展开更多
The angle α between the fault strike and the axial direction of the roadway produces different damage characteristics. In this paper, the research methodology includes theoretical analyses, numerical simulations and ...The angle α between the fault strike and the axial direction of the roadway produces different damage characteristics. In this paper, the research methodology includes theoretical analyses, numerical simulations and field experiments in the context of the Daqiang coal mine located in Shenyang, China. The stability control countermeasure of "pre-splitting cutting roof + NPR anchor cable"(PSCR-NPR) is simultaneously proposed. According to the different deformation characteristics of the roadway, the faults are innovatively classified into three types, with α of type I being 0°-30°, α of type II being 30°-60°, and α of type III being 60°-90°. The full-cycle stress evolution paths during mining roadway traverses across different types of faults are investigated by numerical simulation. Different pinch angles α lead to high stress concentration areas at different locations in the surrounding rock. The non-uniform stress field formed in the shallow surrounding rock is an important reason for the instability of the roadway. The pre-cracked cut top shifted the high stress region to the deep rock mass and formed a low stress region in the shallow rock mass. The high prestressing NPR anchor cable transforms the non-uniform stress field of the shallow surrounding rock into a uniform stress field. PSCR-NPR is applied in the fault-through roadway of Daqiang mine. The low stress area of the surrounding rock was enlarged by 3-7 times, and the cumulative convergence was reduced by 45%-50%. It provides a reference for the stability control of the deep fault-through mining roadway.展开更多
The fiber grouted material can reinforce the tension strength, shear strength as well as the index of fracture ductile, and remarkably improve the endurance of pre-stressed anchor rope under long-time loading. As a re...The fiber grouted material can reinforce the tension strength, shear strength as well as the index of fracture ductile, and remarkably improve the endurance of pre-stressed anchor rope under long-time loading. As a result, it has the better application foreground. Based on the shear log model and Hashin-Shtrikman upper and lower limited theorem, we have studied the mechanism of fiber grouted material applied in pre-stressed anchor rope and material property, and analyzed the effect of resistance strength of bond, resistance distribution of anchor section and the loading-deformation relationship of anchor body.展开更多
中空注浆矿用锚索用6.20 mm 2200 MPa超高强度钢丝因强度要求高,生产难度大,在生产时容易出现断丝,表面处理时采用盐酸两道次浸泡酸洗,酸洗后水冲洗采用先高压水冲洗再浸泡洗然后再高压水冲洗的方式,水冲洗后选用锌系高温快速磷化液,磷...中空注浆矿用锚索用6.20 mm 2200 MPa超高强度钢丝因强度要求高,生产难度大,在生产时容易出现断丝,表面处理时采用盐酸两道次浸泡酸洗,酸洗后水冲洗采用先高压水冲洗再浸泡洗然后再高压水冲洗的方式,水冲洗后选用锌系高温快速磷化液,磷化时间3~5 min,选用8道次拉拔。采用该工艺生产的钢丝能够满足产品的要求。展开更多
目的评价应用微型骨锚钉(mitek bone anchor)及钢丝固定重建指伸肌腱中央束撕脱伤的疗效。方法应用骨锚钉手术治疗患者(锚钉组)18例,应用钢丝手术治疗(钢丝组)20例患者,疗效评价标准采用Dargan功能评定法进行评定。结果术后随访1～6年,...目的评价应用微型骨锚钉(mitek bone anchor)及钢丝固定重建指伸肌腱中央束撕脱伤的疗效。方法应用骨锚钉手术治疗患者(锚钉组)18例,应用钢丝手术治疗(钢丝组)20例患者,疗效评价标准采用Dargan功能评定法进行评定。结果术后随访1～6年,患指功能锚钉组优16例,良2例。钢丝组优10例,良4例,可4例,差2例。结论应用微型骨锚钉重建指伸肌腱中央束止点比传统的钢丝固定技术更安全可靠。展开更多
文摘An anchor bearing plate transfers the anchoring force from anchor plate to the concrete and the pre-stress is formed in the concrete structure. Currently, the main type of anchor bearing plate is cast iron. It is brittle during transportation and tension process. This paper presents a new type of anchor bearing plate combined stamping with welding forming. The structure of the new type anchor bearing plate is introduced. The stress states of the anchor bearing plate and anchorage zone under work are studied. Various specifications of anchor bearing plate are studied by ANSYS finite element analysis software following the AASHTO specification. The analysis results are compared with the results of the same type of OVM round-shaped anchor plate. The study results show that the new pre-stressed anchor plates combined stamping with welding forming are feasible and more sturdy which can meet the engineering demand.
基金This paper was financially supported by the Project 973 of Chinese National Program of Basic Research （No. 2002CB412701） the National Natural Science Foundation （No. 40502027）the Project of Innovation Program of Chinese Academy of Sciences （No. KZCX2-306）.
文摘During the construction of some large-scale rock engineering,high-steep slopes and insufficient slope stability induced by unloading fissures are often encountered.For the reinforcement of these slopes,some techniques(including conventional pre-stressed anchoring cable and unconventional anchoring hole)are usually utilized,however,having several obvious defects.Thus,it is very difficult for a designer to design an efficient reinforcement scheme for the high-steep slopes.For this reason,the authors develop the pre-stressed anchoring beam technique,in which tensile capacity of pre-stressed structures are fully utilized.It is analyzed that the new technique is characterized by multi-functions,including engineering investigation,efficient reinforcement,drainage,monitoring and urgent strength supplement,and hoped to be extensively applicable in the reinforcement of high-steep slopes.
基金funded by the National Natural Science Foundation of China (52174096, 52304110)the Fundamental Research Funds for the Central Universities (2022YJSSB03)the Scientific and Technological Projects of Henan Province (232102320238)。
文摘The angle α between the fault strike and the axial direction of the roadway produces different damage characteristics. In this paper, the research methodology includes theoretical analyses, numerical simulations and field experiments in the context of the Daqiang coal mine located in Shenyang, China. The stability control countermeasure of "pre-splitting cutting roof + NPR anchor cable"(PSCR-NPR) is simultaneously proposed. According to the different deformation characteristics of the roadway, the faults are innovatively classified into three types, with α of type I being 0°-30°, α of type II being 30°-60°, and α of type III being 60°-90°. The full-cycle stress evolution paths during mining roadway traverses across different types of faults are investigated by numerical simulation. Different pinch angles α lead to high stress concentration areas at different locations in the surrounding rock. The non-uniform stress field formed in the shallow surrounding rock is an important reason for the instability of the roadway. The pre-cracked cut top shifted the high stress region to the deep rock mass and formed a low stress region in the shallow rock mass. The high prestressing NPR anchor cable transforms the non-uniform stress field of the shallow surrounding rock into a uniform stress field. PSCR-NPR is applied in the fault-through roadway of Daqiang mine. The low stress area of the surrounding rock was enlarged by 3-7 times, and the cumulative convergence was reduced by 45%-50%. It provides a reference for the stability control of the deep fault-through mining roadway.
文摘The fiber grouted material can reinforce the tension strength, shear strength as well as the index of fracture ductile, and remarkably improve the endurance of pre-stressed anchor rope under long-time loading. As a result, it has the better application foreground. Based on the shear log model and Hashin-Shtrikman upper and lower limited theorem, we have studied the mechanism of fiber grouted material applied in pre-stressed anchor rope and material property, and analyzed the effect of resistance strength of bond, resistance distribution of anchor section and the loading-deformation relationship of anchor body.
文摘中空注浆矿用锚索用6.20 mm 2200 MPa超高强度钢丝因强度要求高,生产难度大,在生产时容易出现断丝,表面处理时采用盐酸两道次浸泡酸洗,酸洗后水冲洗采用先高压水冲洗再浸泡洗然后再高压水冲洗的方式,水冲洗后选用锌系高温快速磷化液,磷化时间3~5 min,选用8道次拉拔。采用该工艺生产的钢丝能够满足产品的要求。
文摘目的评价应用微型骨锚钉(mitek bone anchor)及钢丝固定重建指伸肌腱中央束撕脱伤的疗效。方法应用骨锚钉手术治疗患者(锚钉组)18例,应用钢丝手术治疗(钢丝组)20例患者,疗效评价标准采用Dargan功能评定法进行评定。结果术后随访1～6年,患指功能锚钉组优16例,良2例。钢丝组优10例,良4例,可4例,差2例。结论应用微型骨锚钉重建指伸肌腱中央束止点比传统的钢丝固定技术更安全可靠。
