- Home
- Companies
- Williams Form Engineering Corporation
- Products
- Williams - Micropiles
Williams - Micropiles
Micropiles are high capacity, small diameter (5” to 12”) drilled and grouted in-place piles designed with steel reinforcement to primarily resist structural loading. Micropiles have rapidly gained popularity for foundations in urbanized areas or in locations with low headroom and restricted access. They are an ideal choice for underpinning or emergency repairs because they can be installed in virtually any ground condition with minimal vibration and disturbance to existing structures. Williams larger diameters of All-Thread Rebar are popular choices for micropile reinforcement.
Williams offers right-hand threaded Grade 75 & Grade 80 All-Thread Rebar in #14 – #32 along with a selection of reducer couplers that can adapt to splice together any larger size bar to any smaller size. Williams also offers Grade 90 All-Thread-Rebar and 150 KSI All-Thread-Bar as alternatives for micropile design applications upon request.
Larger Bar Micropile Cost Saving Advantages
In larger micropile designs, casing diameter is minimized because the effective net area available for reinforcement is optimized with a single larger bar versus smaller bundled bars (see example). There is also an increased rate of production installing a single larger bar versus smaller bundled bars.
Hollow Bar Micropiles
Accepted by the?FHWA in the Micropile Design and Construction Guidelines Manual, Hollow Bars are being used increasingly for micropile applications. Through the increased bond stress resultant from the simultaneous drilling and grouting operation, Hollow Bars are the reinforcement bar choice in collapsing soil conditions.
Using sizes from 32 mm to 130 mm, these Hollow Bars offer up to 1785 kips of strength, up to 16.2 in² of cross sectional reinforcement area, and their section modulus provides considerable bending resistance. A variety of drill bits promise efficient installation and Williams offers a full line of adaptation equipment and rental grout plants necessary for Hollow Bar anchor installation.
Hollow Bar Micropiles
Accepted by the?FHWA in the Micropile Design and Construction Guidelines Manual, Hollow Bars are being used increasingly for micropile applications. Through the increased bond stress resultant from the simultaneous drilling and grouting operation, Hollow Bars are the reinforcement bar choice in collapsing soil conditions.
Using sizes from 32 mm to 130 mm, these Hollow Bars offer up to 1785 kips of strength, up to 16.2 in² of cross sectional reinforcement area, and their section modulus provides considerable bending resistance. A variety of drill bits promise efficient installation and Williams offers a full line of adaptation equipment and rental grout plants necessary for Hollow Bar anchor installation.