[Official Web Site for Helical Piles: A Practical Guide to Design and Installation Welcome to the official web site for the book, Helical Piles: A Practical Guide to Design and Installation, by Howard A. Perko, Ph.D., PE., An unbiased, comprehensive, review of the design, technology, installation, and application of helical piles, screw piles, helical piers, helical anchors, and torque anchors for foundations, retaining walls, and shoring. The book contains example foundations for commercial and residential buildings, boardwalks, and energy structures.]