Search Results for: tar paper and sand concrete

Introduction Repairing spalls with exposed rebar means patching concrete where the surface has chipped away and rebar is visible. Before you dig in, determine if the area can be saved or needs replacement, and plan for proper bonding between old concrete and the patch. Decide on a bonding method based on the site and materials, […]

Introduction Grinding, scarifying, and milling are three removal methods that remove concrete from the surface, each with a different tool and result. Grinding uses a rotating abrasive disk to smooth and flatten the top layer. Scarifying tears and scratches the surface to lift material more aggressively, while milling removes larger sections with a powered drum.

Introduction ASR is a chemical reaction in concrete between alkalis and reactive silica in aggregates that can lead to slow expansion and cracking. In the field, it can look like cracking, blistering, or powdery patches that mimic other problems. Understanding these symptoms helps you tell whether you might be dealing with ASR or something else.

Introduction Concrete surface contamination tests tell you whether a surface is clean enough for bonding by revealing any residual oils, silicones, or waxes. For epoxy or other adhesives, you must verify cleanliness requirements with the product label and local rules, because expectations vary. If unsure, follow a basic check: a dry, dust-free feel and a

Introduction Half-cell potential testing is a quick field check that estimates the likelihood of corrosion on embedded steel by measuring electrical potential at the surface. It’s a screening tool, not a crystal ball, and results should be used with other observations. Always follow the device instructions and local rules when you perform it. To perform

Introduction Crushed glass as aggregate is using recycled glass pieces as the rock substitute in concrete. There is an alkali-silica reaction risk with crushed glass, which varies with glass type, particle size, and the concrete mix. Always check product labels, supplier instructions, and local rules for ASR guidance and suitability. Mitigation strategies include choosing less

Introduction Laitance is a thin, weak surface layer of cement and fines on concrete that can ruin coatings if it isn’t removed. It often feels powdery or dusty and looks lighter or different from the surrounding concrete. If you leave laitance, coatings can fail early and moisture or dirt may trap under the finish. Removal

Introduction Magnesium phosphate concrete repair is the use of magnesium phosphate cement to fix or patch concrete joints and damaged areas. It is presented here as a practical option for small repairs and fast-setting projects. In this guide you’ll also see notes about who contributed to the writing and a publisher’s note to set the