In steel squeeze casting process, the working condition of a punch was very rigorous. The abnormal failure models of an H13 punch, such as plastic rubbed damnification, could not be avoided easily. Based on the analys...In steel squeeze casting process, the working condition of a punch was very rigorous. The abnormal failure models of an H13 punch, such as plastic rubbed damnification, could not be avoided easily. Based on the analysis of the flow stress and the friction-shearing stress of an H13 punch in steel squeeze casting process, the following results were obtained： if the flow stress of an H13 punch was smaller than its friction-shearing stress, these abnormal failures could not be avoided; and if there were some protection measures that enable the flow stress to have a greater value than its friction-shearing one, the abnormal failures would not occur. In the production of 45^# steel valves and catenary system components, the flow stress of a lateral H13 punch without any protection measure was about 29 MPa and its friction-shearing stress was about 51 MPa, then, the abnormal failures occurred; however, when the protection measures of the punch enabled its working temperature to have a value below 682 ℃ its flow stress was greater than its friction-shearing stress, and the abnormal failures were avoided.展开更多
This paper presents a case history study on the geologic investigation and numerical modeling of areactivated landslide in the County of Santa Clara, California to identify the failure mechanism. Thelandslide occurred...This paper presents a case history study on the geologic investigation and numerical modeling of areactivated landslide in the County of Santa Clara, California to identify the failure mechanism. Thelandslide occurred on an approximately 18.3-m high, north-facing slope during March 2011. The landslidemeasured about 33.5 m in width and about 51.8 m in length. Along the toe of the slope, a residentialstructure with a swimming pool was built on a cut and fill pad and there are several other structurespresent along the western side of the pad. The landslide occurred immediately to the south of theresidential building and moved northward between the County Road A and the house＇s side yard. Themovement of the landslide resulted in damaging the west-bound traffic lane of County Road A andencroached onto the paved driveway for the residential property. An investigation was performed toidentify the failure mechanism of the landslide to conclude whether Road A re-alignment by the Countyor prominent cutting performed along the lower portion of the slope by the homeowner during 2000through 2004 contributed to the reactivation of the old landslide deposit. The investigation included sitereconnaissance, reviewing available published geologic information, reviewing site-specific geologic andgeotechnical data developed by other consultants, and performing numerical modeling. The outcomes ofthe investigation indicate that the primary causation for the reactivation and failure of the subject preexistinglandslide is the prominent cutting performed along the lower portion of the slope during 2000through 2004 and water tank cut bench. The Road A re-alignment did not contribute to the reactivationof the old landslide deposit. 2015 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. All rights reserved.展开更多
文摘In steel squeeze casting process, the working condition of a punch was very rigorous. The abnormal failure models of an H13 punch, such as plastic rubbed damnification, could not be avoided easily. Based on the analysis of the flow stress and the friction-shearing stress of an H13 punch in steel squeeze casting process, the following results were obtained： if the flow stress of an H13 punch was smaller than its friction-shearing stress, these abnormal failures could not be avoided; and if there were some protection measures that enable the flow stress to have a greater value than its friction-shearing one, the abnormal failures would not occur. In the production of 45^# steel valves and catenary system components, the flow stress of a lateral H13 punch without any protection measure was about 29 MPa and its friction-shearing stress was about 51 MPa, then, the abnormal failures occurred; however, when the protection measures of the punch enabled its working temperature to have a value below 682 ℃ its flow stress was greater than its friction-shearing stress, and the abnormal failures were avoided.
文摘This paper presents a case history study on the geologic investigation and numerical modeling of areactivated landslide in the County of Santa Clara, California to identify the failure mechanism. Thelandslide occurred on an approximately 18.3-m high, north-facing slope during March 2011. The landslidemeasured about 33.5 m in width and about 51.8 m in length. Along the toe of the slope, a residentialstructure with a swimming pool was built on a cut and fill pad and there are several other structurespresent along the western side of the pad. The landslide occurred immediately to the south of theresidential building and moved northward between the County Road A and the house＇s side yard. Themovement of the landslide resulted in damaging the west-bound traffic lane of County Road A andencroached onto the paved driveway for the residential property. An investigation was performed toidentify the failure mechanism of the landslide to conclude whether Road A re-alignment by the Countyor prominent cutting performed along the lower portion of the slope by the homeowner during 2000through 2004 contributed to the reactivation of the old landslide deposit. The investigation included sitereconnaissance, reviewing available published geologic information, reviewing site-specific geologic andgeotechnical data developed by other consultants, and performing numerical modeling. The outcomes ofthe investigation indicate that the primary causation for the reactivation and failure of the subject preexistinglandslide is the prominent cutting performed along the lower portion of the slope during 2000through 2004 and water tank cut bench. The Road A re-alignment did not contribute to the reactivationof the old landslide deposit. 2015 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. All rights reserved.
