Retrofit Standoff Post Base for Uplift Resistance
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Solution Overview
Problem
Existing connections for securing wood posts to concrete foundations lack resistance to uplift forces such as those from earthquakes, hurricanes, and tidal forces, and none are suitable for retrofitting using a single piece of sheet metal.
Innovation Solution
A sheet metal connector that attaches to the sides of the wood post and can be retrofitted by sliding it between the post and the foundation, featuring a compact box design with side leg members that bear on the foundation's upper surface, providing strong attachment and resistance to uplift forces.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a connector is designed to attach to the bottom surface of the post, then it can be securely attached to the foundation, but it cannot be retrofitted after the post is already in place
Solution Approach 1:
Instead of attaching the connector to the bottom surface of the post as in conventional designs, this invention inverts the attachment approach by having the connector attach to the sides of the post. The upright arms extend upward to engage with the post sides, allowing the connector to be slipped into place below the post and secured from the sides, enabling retrofit installation while maintaining secure attachment.
Solution Approach 2:
The connector acts as an intermediary element that bridges the gap between the existing post and the foundation. By designing the connector with upright arms that engage the post sides and a base that attaches to the foundation, it mediates the connection between these two components, enabling both new construction and retrofit applications.
2Adaptability or versatility
If multiple separate parts are used to form the connector, then assembly flexibility is improved, but manufacturing cost, inventory complexity, and installation time increase
Solution Approach 1:
This invention merges multiple functional components into a single unitary connector formed from one piece of sheet metal. The connector integrates the base member, upright arms, and attachment features into one monolithic structure, eliminating the need for multiple separate parts. This reduces manufacturing complexity, inventory requirements, and installation time while maintaining the necessary assembly flexibility through the integrated design.
Solution Approach 2:
The unitary connector performs multiple functions within a single component: it provides structural support, resists uplift forces, attaches to the post sides, and secures to the foundation. This multi-functionality is achieved through the integrated design that combines all necessary features into one piece, reducing the need for multiple specialized parts.
3Quantity of substance
If the connector uses a compact box design with side leg members, then material use is minimized and bearing strength is maximized, but the complexity of forming the connector increases
Solution Approach 1:
The connector utilizes parameter changes in the sheet metal forming process to create the compact box design with side leg members. By varying the bend angles, fold directions, and dimensional parameters during the progressive die stamping process, the flat sheet metal blank is transformed into a three-dimensional box structure with upright arms and bearing surfaces, achieving compact geometry and optimized material distribution.
Solution Approach 2:
While the connector is formed from a single piece of sheet metal, the design creates a composite-like structure through folding and bending, where different portions of the same material assume different spatial orientations and functional roles. The side leg members, base member, and upright arms form a composite geometric structure that maximizes bearing strength while minimizing material use.
4Reliability
If the connector is designed to provide maximum resistance to uplift forces, then structural reliability is improved, but the size and material requirements increase
Solution Approach 1:
The connector resists uplift forces by transferring them to another dimension - horizontally to the foundation through the side-attached upright arms and base member, rather than relying solely on vertical bearing. The side leg members folded in under the base create a compact box structure that distributes uplift forces across multiple attachment points on the foundation, achieving high uplift resistance in a compact form factor.
Solution Approach 2:
The compact box design creates a composite geometric structure that efficiently resists uplift forces. The integrated arrangement of the base member, upright arms, and side leg members forms a rigid three-dimensional structure that distributes and resists uplift loads across multiple points, achieving maximum uplift resistance with minimal material volume.
Data Source
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AI summary
A post to foundation connection (1) made with a connector (7) that can be installed as a retrofit after the post (4) is already in place, with fastener attachments (14) that are made to either side of the post rather than under it. The connector can be slid into place below the post, between it and the foundation, after which it can be attached to the foundation (2) and the post.