Nanoindentation Characterization of a Ternary Clay-Based Composite Used in Ancient Chinese Construction

Abstract

Ternary clay-based composite material (TCC), composed of lime, clay and sand, and usually modified with sticky rice and other organic compounds as additives, was widely used historically in Chinese construction and buildings due to its high mechanical performance. In this study, to gain an insight into the micromechanical mechanism of this cementitious material, the nanomechanical properties and volume fraction of mechanically different phases of the binder matrix are derived from the analysis of grid nanoindentation tests. Results show that there are five distinct mechanical phases, where the calcium silicate hydrate (C-S-H) and geopolymer present in the binder matrix are almost identical to those produced in ordinary Portland cement (OPC) and alkali-activated fly-ash geopolymer materials in nano-mechanical performance. The nano-mechanical behavior of calcite produced by the carbonation of lime in this binder is close to the calcite porous outer part of some sea urchin shells. Compared to OPC, the C-S-H contained in the TCC has a relatively lower ratio of indentation modulus to indentation hardness, implying a relatively lower resistance to material fracture. However, the geopolymer and calcite, at nearly the same volume content as the C-S-H, help to enhance the strength and durability of the TCC by their higher energy resistance capacity or higher strength compared to the C-S-H. Rediscovering of TCC offers a potential way to improve modern concrete’s strength and durability through synergy of multi-binders and the addition of organic materials if TCC can be advanced in terms of its workability and hardening rate.

Mechanical and thermal behaviors of Ti36-Al16-V16-Fe16-Cr16 high entropy alloys fabricated by spark plasma sintering: An advanced material for high temperature/strength applications

“…46,47 During the loading regime in nano indentation, elastic and plastic deformation occurred; but during unloading regime, only elastic deformation occurred. 48 So, a plot of ratio of final penetration depth (Hf) and maximum penetration depth (Hm) i.e. Hf/Hm (Figure 9(a)) was used to confirm the HEA elasticity behaviour.…”

Study on Carbonation of Porcine Blood Hydrogel in the Composite Mortar of Ancient Chinese Architectural Painting

“…The earliest organic–inorganic composite building mortar was discovered in China and dates to 2300 BCE [ 9 ]. It has been shown that ancient traditional lime-based binders contained organic additives such as glutinous rice [ 10 , 11 , 12 , 13 ], tung oil [ 7 , 14 , 15 ], blood [ 16 , 17 , 18 , 19 ], egg white [ 20 , 21 ], sugar [ 20 ], gelatin [ 6 , 9 ], and peach gum [ 2 ]. Similarly, these lime-based mortars also emerged in other countries around the world.…”

“…In Myanmar, glutinous rice and proteins were added to building mortars to meet higher living requirements [ 6 ]. From reports in the literature such as glutinous rice–lime mortar [ 11 , 24 , 25 , 26 , 27 ], tung oil–lime mortar [ 27 , 28 , 29 ], blood–lime mortar [ 17 , 18 , 19 ], egg white–lime mortar [ 20 , 21 , 28 ], and sugar–lime mortar [ 20 , 28 ], the same conclusion that organic–inorganic composite mortars have strong adhesion properties could be drawn. In these natural organic matters, blood–lime mortar has received special attention.…”

A New Bin Size Index Method for Statistical Analysis of Multimodal Datasets from Materials Characterization

“…Depending upon the nature of the datasets (e.g., one, two, or multi-dimensional datasets), PDF, cumulative distribution function (CDF), and Gaussian mixture modeling (GMM)-based statistical deconvolutions are well-developed and readily available at present. For example, numerous work involving one or more of the aforementioned deconvolution methods has been reported for characterizing the mechanical properties of multiphase composites using nano/micro indentation 3,[6][7][8][9][10] . In fact, most of the aforementioned materials characterization problems usually involve only univariate datasets, offering the PDF-based deconvolution certain advantages over the CDF and GMM.…”