The Sinorock® hollow anchor bar ground engineering products can be used in permanent applications if the correct installation and anchorage protection are utilized without any additional corrosion protection. The high yield steel has a low carbon content that exceeds the Carbon Equivalent Value (CEV) of ≤ 0.55% as prescribed in ASTM A706. A result of this low carbon content is that the steel is very ductile and is not susceptible to stress, corrosion cracking, or hydrogen embrittlement.

Also, unlike Rope Thread (R-thread), the Sinorock® Hollow Bar thread is course, widely spaced and has a grove taken out of the crown.This thread type conforms to ASTM A706 and induces controlled cracking of the grout along the length of the bar.


1. Utilization of a Sinorock® Hollow anchor bar as the reinforcing Bar. From the static point of view, a hollow anchor bar is superior to a solid rod of the same cross sectional area with respect to bending moment,shear resistance and surface bond/friction.

2. The Sinorock® Hollow anchor bar is manufactured from high yield micro alloy, high quality structural steel offering high notch toughness > 40J @ -20 Celcius.This steel is not affected by hydrogen embrittlement or by stress crack corrosion. It has at least the mechanical properties and chemical compositions of ASTM A-706.

3. The threads on the Sinorock® Hollow anchor bar are formed much like the ribs on a reinforcing bar fabricated according to ASTM-A-706. The deep TITAN threads result in 2.4 times higher bond friction compared to standard drill steel rope-threads.

4. Continuous threads guarantee that the Sinorock® Hollow Bar can be cut or coupled anywhere along its length. A thread pitch of 6 degrees eliminates the need for locking nuts at each coupling.

5. Certified to ISO 9001.