Anchor fasteners for securing structures to concrete, brick, and stone. Mechanical types: wedge (expansion), drive-in, and ceiling anchors. Chemical types: capsule and injection (resin + fastener) — for critical fixings in cracked concrete. Wedge anchor: bolt with cone and expansion sleeve, tightening the nut wedges it in the hole. Pull-out load: M8 — 10–15 kN, M16 — 35–50 kN (in concrete C20/25). Chemical anchor: two-component resin (epoxy, vinyl ester, polyester) + stud — calculated load is 20–50% higher than mechanical. Certification: ETA (European Technical Assessment) — mandatory for critical fixings (seismic, fire). Hilti, Fischer, MKT — leading brands. Packaging: boxes, cartridges (chemical). Chemical anchor vs mechanical: chemical works in cracked concrete, hollow materials, near edges — where mechanical is unreliable. Curing time depends on temperature: at +5°C — up to 2 hours, at +20°C — 20–45 min. Load calculation — according to ETA or manufacturer's technical guide with safety factors.