Complex sentence: With the introduction of modern portland cement (OPC) during the 19th century the use of lime mortar in new constructions gradually declined, largely due to portland's ease of use, quick setting, and high compressive strength.
Split into simpler sentences: With the introduction of modern portland cement (OPC) during the 19th century, the use of lime mortar in new constructions gradually declined. This was largely due to portland's ease of use, quick setting, and high compressive strength.