Portland cement
Cemento Portland
- Date
- 1824 · confidence high
- Place
- Leeds, England, United Kingdom
- Credited to
- Joseph Aspdin (patent); Isaac Charles Johnson (modern cement, 1845)
- People
- 👤 Joseph Aspdin1778–1855
- Field
- Tools
⚠️ Disputed: the sources disagree.
What it is
An artificial cement obtained by calcining limestone and clay to the point of clinkering, which sets underwater and reaches great strength. It is the binder that defines modern construction.
Aspdin's 1824 product did not reach clinkering temperature; true Portland cement was achieved by Johnson at Swanscombe (Kent) in 1845, and Vicat had established the underlying theory in France.
What it led to
- Concrete as a mass material
- Hydraulic works, sewers and harbours
- The cement industry and large-scale quarrying
- 20th-century reinforced-concrete architecture
Built on
- Calcium1808
- Artificial hydraulic lime from calcined limestone and clay (Vicat)1817-1818
- Parker's Roman cement (1796)
- John Smeaton's hydraulic lime (Eddystone Lighthouse, 1756)
- Louis Vicat's research (1817)
Made possible
- Underwater tunnel with tunnelling shield (Thames Tunnel)1825-1843
- London main drainage system1858-1865
- Early reinforced concrete1849-1867
- Shotcrete (gunite) by Akeley1907-1911
- Prestressed concrete1928
- Alkali-activated cements and geopolymers1957
- Self-compacting concrete1988
- London sewerage system
- Underwater tunnel (linings)