A characterization method for the fifth-century traditional mortars in the land walls of Constantinople, Yedikule

A characterization method was designed to improve understanding of ancient mortars used in the land walls of Istanbul, Turkey. The mortars had hydraulic properties where slaked lime was the binder and crushed brick was the aggregate. For characterization purposes simple chemical and petrographic analyses may be sufficient. However, further scientific research based on instrumental analysis is needed for an understanding of ancient lime technologies, provenance of the materials and deterioration processes. Besides simple chemical and petrographic analysis, this paper describes the differential thermal analysis (DTA), inductively coupled plasma analysis (ICP), X-ray diffraction analysis (XRD), scanning electron microscope-energy dispersive X-ray analysis (SEM-EDX) and mercury intrusion tests that were conducted to evaluate the binders and aggregates of the samples. Their physical and mechanical properties were also determined, and salt decay is discussed. It was seen that limestone chips and river sand were used as aggregates, in addition to crushed brick. The brick dust served as an artificial pozzolanic additive. Salt decay originated from sea spray and air pollution.