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一些技术标准对预应力锚杆的规定存在着一些争议。土层锚杆水平刚度系数公式存在着严重缺陷且意义不明确,建议修改完善。基本试验时:稳载期间稳定指标0.1 mm为笔误,应为1.0 mm;不应减短锚杆锚固段长度,因为锚固段较短时得到的黏结强度偏高;为得到黏结强度极限值,试验最大荷载应为破坏荷载。验收试验不合格时扩大抽检比例宜为不合格锚杆数量的2倍。蠕变试验时蠕变率计算公式应明确计时方法,否则蠕变率指标无意义。不需严格限制自由段长度,可为4～6 m以便更好地控制支护体系变形。临时锚杆设计使用期宜从2年提高到5年,以更好地满足目前工程建设需要。二次注浆在注浆体强度达到5 MPa后进行这条规定很难执行,建议改为在注浆体初凝后终凝前进行。
Some technical standards prestressed anchor rod there are some controversial provisions. The formula of horizontal stiffness coefficient of soil anchor has serious defects and the meaning is not clear, so it is suggested to modify and perfect it. The basic test: stable index during the steady-state load of 0.1 mm is a typo, should be 1.0 mm; should not be shortened anchor bolt length, because the anchor section is too short to get the bond strength is too high; in order to get the bond strength limit, the test The maximum load should be the destructive load. Acceptance test failed to expand the sampling ratio should be unqualified 2 times the number of bolts. Creep test creep rate formula should be clear timing method, or creep rate index meaningless. There is no need to strictly limit the length of the free section, which can be 4 ~ 6 m in order to better control the deformation of the support system. Temporary bolt design should increase the useful life from 2 years to 5 years to better meet the current construction needs. Secondary grouting in the grout strength reached 5 MPa after the implementation of this provision is difficult to implement, it is recommended to change to the grout after the initial setting of coagulation before the final setting.