Reinforcement & Anchoring Cintec™ Services
Cintec™’s technical excellence is assured by highly qualified and experienced engineers, heritage architects, conservators, computer modelling experts and other specialists—in-house and independent—who together offer depth of knowledge and worldwide experience. Cintec™ can generally develop design solutions for unusual masonry structural problems and can offer clients:
- Consulting services, including assessment, design and testing, to assist the principal designers of a project in determining its viability
- Turnkey services, if required, for special projects for the engineering, design, manufacture and installation of anchoring systems
- Unparalleled experience and expertise
The first stage of any Cintec™ project involves assessing the problem for preparing to design the appropriate Cintec™ anchoring solution. The same project can pose many different technical challenges, depending on the structure and the functions of its various components. Cintec™’s engineers and designers work with the client or the project engineer or architect to obtain as much information as possible for exploring options to develop the anchoring solutions needed.
Design Parameters for Stone, Brick and Terra Cotta Masonry
- For many applications and designers, the use of Allowable Stress Design (ASD), is appropriate, and thus the focus of this manual is on that method. It is also known as Working Stress Design (WSD) in parts of North America. The same procedures can be adapted to the Limit State Design (LSD) method or Load Factored Resistance Method (LFRD) where design consistency is required with other parts of the project.
- Bond pull out strength is typically 65PSI (working stress) on the circumference of the drilled hole. This is based on 4x safety factor based on actual full scale load tests. This may be reduced in very dense, smooth substrates like granite to as low as 30 PSI
- Steel is AISI Type 304 stainless with a yield of 29,000 PSI. We use 0.6 as the strength reduction factor for WSD in bending, tension and shear.
- Safe bearing strength for shear loads and/or bending stresses from eccentric loads on sound brick masonry is 300 PSI. Bearing area is calculated on one- half the circumference of the hole, not the projection of the hole diameter.
- The sum of the interaction formula for combined stresses shall not exceed 1.0
- Pull out and bearing strength of the substrate is based on the ACI standard procedure using an appropriate diagonal tensile stress. Pull out strength in terra cotta units is based on a very conservative value and load tests have always proven that failure load is much higher than we calculate.
- The anchors system tends to fail in the substrate. The steel anchor body typically does not fail, and the grout element does not fail in crushing or pull -out if the grout installation has been performed in accordance with Cintec™ requirements. Therefore design should focus primarily on determining the properties of the substrate.