Soil nail system

Soil Nail System

Williams Grade 75 and 150 KSI All-Thread-Bar soil nail components create an in-situ reinforcement system for the stabilization of excavations and slopes during top-down construction. Oversized holes of 4" to 10" in diameter are drilled and the centralized soil nail component is placed. The drill hole is then tremie grouted with Williams Wil-X-Cement grout. After the drill hole grout is cured, the soil nails may be torque tensioned against the protective shotcrete face to a slight load if desired.

Suggested working loads on common soil nails should not exceed 60% of the bar's ultimate strength. Pull out capacity is a function of drill hole diameter, depth, over burden stress and the angle of internal friction of the in-situ soil. Field tests are recommended to establish necessary bond lengths. However, typical anchorages in granular soils have yielded pull out strengths of 2-10 kips per foot of embedment on lengths over 10 feet.

Williams All-Thread Soil Nails Offer:

Rugged thread with precision fit for durability and ease of use.
360° of concentric thread for unmatched grout to bar bond.
Mechanical stop-type couplers able to develop 100% of the bar's tensile capacity for the most reliable bar to bar connections available.
Grades 75 and 150 KSI with full circular effective areas.
Several options of corrosion protection including epoxy coating, galvanizing, cement grout and multiple corrosion protection for both temporary and permanent use.
Manufacturing versatility unmatched by any soil nail supplier in North America.
Connection abilities with structural and non-structural wall face attachments.

Cross Section of factory grouted duct and bar.

One Sided Wall Forming

Williams offers an extensive line of concrete forming hardware that can be used in conjunction with soil nails for permanent wall forming. Williams offers she-bolts and coupling systems capable of developing 100% of the bar strength.

Stress Distribution of a Soil Nail
As the soil loads the grouted nail, the stress starts at the back of the nail behind the active zone failure plane and reaches a maximum stress at the failure plane. The stress dissipates from the failure plane through the active zone to the flexible front fascia. The shotcrete fascia can be very thin, as there is very little force at the face.