Many stone arch bridge feature subtle design features that are tucked away out of sight within the structure, which can greatly complicate rehab and load handling calculations.
In this post we will briefly examine what makes the various types of commercially available mortar mixes different, and how this relates to repairing historic structures.
Bulging walls in the approaches and spandrel walls of a stone arch bridge indicate excessive force against them. This type of problem is fairly simply addressed.
Longitudinal cracking is a common defect on stone arch bridges. While often not overly serious, under the right conditions this cracking can indicate a major problem.
Regular checking on the progress of any and all deterioration of a stone bridge can allow serious problems to be corrected early, saving future expense and trouble.
The design of a stone bridge, which often reflects the era of its construction, determines how critical mortar condition is for long-term stability.
Here are several ways to strengthen a stone arch bridge, ranging from distributing loads over the arch to relieving the bridge from load altogether.
To determine how to strengthen a stone arch bridge, it helps to understand how it behaves when overloaded in order to understand the forces at play.
Mortarless stone arch bridges need extra care to ensure they are not overwhelmed by foliage and that friction between stones remains high.
A key concern when maintaining a mortarless stone arch bridges is how stones can be worked loose by vibration. There are ways to prevent this.