Articles

The changing of the 2021 International Building Code (IBC) to 18 story mass timber buildings has opened a door to new possibilities, but it has also created an array of new problems for engineers to solve. Naturally, as the scale of a design increases, the complexity, as well as the service loading tends to rise. Mass timber is no exception. As with all buildings, forming complete load paths is vital to the safety of the structure and its occupants. The connections bridging members together should be chosen with care. Pioneering new mass timber design can be intimidating, especially when faced with design forces other...

What is an EJ?  An engineering judgment, or EJ as they are commonly known, is a drawing or group of drawings typically generated by a firestop manufacturer for a customer’s jobsite-specific application. They are recommended as a solution when a customer’s jobsite condition deviates from a tested firestop design/system.  What is their purpose?  Contractors consistently encounter unique jobsite conditions requiring new penetrations through fire-rated assemblies regardless of how many firestop systems are tested and approved by third-party testing agencies. Custom drawings are sometimes needed in order to provide the...

Anchors designed for use in concrete and masonry develop resistance to loading on the basis of one or more of the following mechanisms: Friction: This is the mechanism used by most post-installed mechanical expansion anchors to resist loads, including the KWIK Bolt TZ, HSL-3 and HDI anchors. The frictional resistance resulting from expansion forces generated between the anchor and the wall of the drilled hole may also be supplemented by local deformation of the concrete. The frictional force is proportional to the magnitude of the expansion stresses generated by the anchor. Torque-controlled expansion anchors like...

Hilti's Anchor Channel (HAC-V) portfolio has been extended to keep up with construction trends and a wider range of application requirements. The HAC portfolio includes anchor channels with rounded head anchors (HAC-V and HAC-V-T), rebar anchors (HAC-V Rebar XT(S) and HAC-V-T Rebar XT(S)), and a combination of rounded head anchors and rebars (HAC-V EDGE Lite, HAC-V-T EDGE Lite, HAC-V EDGE, and HAC-V-T EDGE). The HAC Library is available in pdf and dwg format. The latest HAC Library can be downloaded from the link below: https://www.hilti.com/content/hilti/W1/US/en/engineering/technical-information/specification...

HILTI ANCHORS Hilti combines world class anchoring products with system solutions and comprehensive performance data to meet the needs on every job site. Our Technical Services team, consisting of Field Engineers and the Hilti Engineering Technical Services group will help you find the right solution to your next anchor design challenge. HILTI ANCHOR FASTENING TECHNICAL GUIDE Our new North American Product Technical Guide Volume 2: Anchor Fastening Technical Guide is now available online and will be available soon through your Hilti Field Engineer. This guide provides anchor design information for all o...

The American Concrete Institute (ACI) standard titled Building Code Requirements for Structural Concrete (ACI 318) provisions for “shear friction” consider an interface between two concrete surfaces over which shear acts. The design premise is that developing the yield strength of a reinforcing bar on each side of the interface will clamp the two concrete surfaces together, thereby resisting the applied shear acting on the interface. In reality, yielding the bars on one or both sides of the interface, such as assumed when using the ACI 318 shear friction method, is difficult to achieve. However, a shear friction desig...