Precast Foundation Column Assembly for Ground-Isolated Wood Posts
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing construction methods for post-frame buildings face challenges in preventing degradation of wooden frame posts and uplift due to seasonal freeze-thaw cycles, requiring additional on-site concrete and anchor pins.
Innovation Solution
A precast concrete column assembly with a unitary body featuring a smaller upper portion and larger lower portion, integrated with a bracket and connecting rods, supports wooden posts, minimizing ground contact and enhancing load-bearing capacity without additional foundation pads or on-site concrete.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If wooden frame posts are set directly on foundation pads in holes in the ground, then the construction process is simple, but the wooden posts degrade due to direct contact with the ground
Solution Approach 1:
A precast concrete column serves as an intermediary element between the wooden frame post and the ground foundation pad. The column's upper portion receives the wooden post through a bracket arrangement, while the lower portion with increased dimensions rests on the foundation pad, preventing direct ground contact and eliminating the need for ground contact treatment of the wooden post.
2Reliability
If a concrete post is used with a separate foundation pad, then the post is protected from ground degradation, but additional anchor pins and on-site concrete are required to prevent uplift from freeze-thaw cycles
Solution Approach 1:
The foundation pad, concrete column, and anti-uplift footing are merged into a single precast concrete column assembly. The lower portion of the column has increased cross-sectional dimensions that extend radially outward to define a footing, integrating the anti-uplift function directly into the column structure itself, eliminating the need for separate anchor pins and on-site concrete pouring.
3Ease of manufacture
If the column has uniform cross-sectional dimensions, then the manufacturing is simpler, but the load-bearing capacity and anti-uplift performance are reduced
Solution Approach 1:
The concrete column features varying cross-sectional dimensions along its length, with the upper portion having smaller dimensions for receiving the wooden post and the lower portion having increased dimensions for enhanced load-bearing capacity and anti-uplift performance. This local variation in geometry optimizes the structural performance at different locations of the column.
Data Source
AI summary
A foundation column assembly is used to support a wooden post of a building frame. The column assembly includes a concrete body supporting a bracket at the top of the concrete body for fastening the wooden post above the concrete body. Connecting rods embedded in the concrete body are fixed to the bracket. The concrete body of the column has an upper portion having cross-sectional dimensions which are equal to or less than corresponding dimensions of the wooden post and a lower portion having cross-sectional dimensions which are greater than the upper portion. The column assembly is inserted into a hole formed in the ground such that backfilling material surrounds at least part of the upper portion while the bracket assembly protrudes from the ground to anchor the wooden post relative to the ground while isolating the wooden post from the ground.