1、锚索弹性位移是否在理论计算值范围内；锚索张拉过程中就是以伸长值及张拉油泵油管的压力表读数来控制张拉值的，一般先理论计算在每级张拉压力下伸长值，现场张拉过程中对应，就可以确定已达到相应设计张拉值。   

2、锚索在最大荷载下变形是否稳定。这个问题比较复杂，可能跟锚头灌浆及地质情况、锚墩及孔口岩体等都有关系，遇到具体问题后具体分析了。一般钻孔钻好后，要做孔内电视或声波测试，锚头深度是根据实际情况调整深度的，避免锚头位移影响张拉。另外在荷载下锚墩和锚墩周围岩体也可能发生位移，都会对张拉锁紧产生影响。锁紧后锚索的应力一般都会是变化的，要么衰减要么增加。锚杆加载分级 锚索分级张拉的级数应该是设计提供吧。

1, the anchor cable elastic displacement is within the scope of the theoretical calculation values; Anchor cable tensioning in elongation and tension in the process of oil pump tubing pressure gauge readings to control tension values, general theoretical calculation of first grade in each of the tensioning elongation under stress, the tension in the process of corresponding, can determine the corresponding design has reached the tension values.

2, anchor cable under the maximum load, deformation is stable. This problem is complicated, it may be with the anchor head grouting, anchor pier and orifice and the geological condition of rock mass, etc have relations, encounter after the specific issue concrete analysis. General drilling, drilling hole to do TV or sound wave test, the depth of the anchor head is according to actual condition adjust depth, avoid the displacement of the anchor head impact tension. Another anchor pier under load and anchor block rock mass around may also ?

3、锚杆的实际弹性伸长量怎么来确定？在实际做试验时，实测的锚杆位移量包括：设备安装所引起的一部分变形（如锚杆一开始并没有完全拉直，需在一定荷载作用下才能变直）和锚杆的实际弹性伸长。锚杆的弹性伸长量=实测总的位移量-设备安装所引起的部分变形。

4、锚杆自由长度的确定
锚杆自由长度的确定必须使锚杆锚固于比破坏面更深的稳定地层上，以保证锚杆系统的整体稳定性；使锚杆能在张拉荷载作用下有较大的弹性伸长量，不致于在使用过程中因锚头松动而引起预应力的明显衰减。《建筑基坑支护技术规程》(JGJ 120-99)中规定锚杆自由长度不宜小于5m并应超过潜在滑裂面1.5m。

3, how to determine the actual elastic elongation of anchor? In practical experiment, the bolt displacement measured include: equipment installation part caused by the deformation (such as the bolt is not entirely straight at the beginning, should be under a certain load to straighten) actual elastic elongation and anchor. Anchor = elastic elongation of the measured total displacement - part deformation caused by installation of equipment.

4, free length of anchor
Free length of anchor bolt anchorage must be made on the stable than failure face deeper strata, to ensure the overall stability of anchor system; Can make the bolt under tension load is larger elastic elongation, not in use process because of the prestressed anchor head is loose caused obvious attenuation. The construction of foundation pit supporting technology