The determination of cement and sand content in an aged cement mortar is a challenging problem for civil engineers. Techniques like x‐ray diffraction (XRD), thermogravimetric analysis (TGA) and electrochemical impedance spectroscopy (EIS) are well established, which can give some insight of the hydrated products. The present study is an attempt to use x‐ray photoelectron spectroscopy (XPS) technique for the evaluation of ordinary Portland cement (OPC), sand (aggregate) composition and carbonation study in hardened cement mortar. Carbonation analysis and cement to sand ratio for all mortar compositions has been determined and studied in detail in the present work. The C 1s spectra of cement mortar with ratios 1:1, 1:3 and 1:6 shows carbonate formation on the surface with 21, 40 and 32 atomic percent, respectively. An increase in SiO₂ content corresponding to sand is observed for all three mortar mix. The formation of silica gel due to carbonation has not been observed in the mortar samples. The cement to sand ratio for all three mortar mixes is found to be in 20–30 percent error limit due to the heterogeneous nature of the mortar system.

中文翻译：

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X射线光电子能谱研究碳化水泥砂浆中水泥与砂比的研究

对老化的水泥砂浆中水泥和砂含量的测定对于土木工程师而言是一个具有挑战性的问题。诸如X射线衍射（XRD），热重分析（TGA）和电化学阻抗谱（EIS）之类的技术已得到很好的建立，可以为水合产物提供一些见识。本研究是尝试使用X射线光电子能谱（XPS）技术评估硬化水泥砂浆中的普通硅酸盐水泥（OPC），砂（骨料）组成和碳化研究。在本工作中，已经确定并详细研究了所有砂浆组合物的碳化分析和水泥砂比。比例为1：1、1：3和1：6的水泥砂浆的C 1s光谱显示表面碳酸盐形成的比例分别为21％，40％和32％。SiO增加对于所有三种砂浆混合物，观察到对应于沙子的₂含量。在砂浆样品中未观察到由于碳化而形成硅胶。由于砂浆体系的非均质性，所有三种砂浆混合物的水泥砂比均处于20％至30％的误差极限内。