No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
Light weight concrete of Yangshao Period of China: The earliest concrete in the world
Abstract
During 1970s, the residential remains of the Yangshao Period were discovered at the Dadiwan site in Qin’an County, Gansu Province, China. With carbon-14 dating, scanning electron microscope (SEM), thermal expansion analyzer, polarizing microscope (PLM), and X ray diffraction (XRD), the microstructures and chemical compositions of the pottery shard, floor materials of the housing site, kunkur, calcined kunkur, ginger nut (calcium concretion) from the Dadiwan site were analyzed and researched. Analysis and simulation tests were also carried out to study the hydratability of calcined ginger nut and calcined kunkur, and the manufacturing process of the residential floors. The research shows that the floor was made of a light concrete formed by the mixture of aggregate of calcinated ginger nut (locally deposited), red clay and kunkur. The dicalcium silicate (C2S) from the floor material of the housing site is one of the main constituents of modern cement, and the floor is also similar to modern concrete in nature. Therefore, the floor material of the housing site at the Dadiwan site was the earliest man-made concrete in the world ever discovered.
... Among these materials, tabia (三合土 in Chinese), an ancient composite of earth, sand, and lime, holds significant value in traditional building technology due to its unique properties and wide applications. Used extensively in ancient China for constructing city walls, tombs, mausoleums and coastal fortifications [1], tabia's origins date back at least 5000 years to Dadiwan, Gansu Province, China [2]. The Ming Dynasty technical text "Tian Gong Kai Wu" by Song Ying Xing documents its preparation method, prescribing a mixture of river sand, earth, lime, and additives like sticky rice and kiwi vine juice to achieve durability [3]. ...
... No purplish-red color was observed in either the supernatant or the precipitate (Fig. 4a); only the inherent color of the diluted KI-I 2 reagent was visible. This suggests two possible explanations: (1) sticky rice soup may not have been incorporated into the preparation of the archaeological tabia samples; (2) if added, the quantity of sticky rice soup was insufficient, or it may have degraded to undetectable levels due to prolonged environmental exposure. Consequently, starch was not detected in the tabia samples, confirming the 1004 cm −1 band observed in the infrared spectra (Fig. 2b) corresponds to the stretching vibration of the Si-O bond. ...
The Lin Yimu’s tomb in Zhejiang Province, China, is a significant Qing Dynasty tabia structure that, despite relatively good preservation, has suffered damage from weathering, necessitating urgent restoration. In this study, we conducted a comprehensive scientific analysis of archaeological samples from the tabia of Lin Yimu’s tomb, employing a range of analytical techniques including X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM/EDX), Fourier transform infrared spectroscopy (FTIR), chemical methods, and measurements of hardness and strength. Analytical results revealed that the main phases of the sample are calcite, quartz, illite/mica, feldspar, with a minor presence of Tung oil. The proportion of calcium carbonate is approximately 27%, and the ratio of earth to sand is 1:2, suggesting a raw material formula mass ratio of lime-earth-sand of 3:4:8. The surface hardness of the sample is measured at 293 ± 15 HL, with a compressive strength of 5.5 ± 0.2 MPa. The sand used in the raw material has a medium particle size of 250 μm, while earth particles are predominantly around 17 μm. The sample exhibits a porosity of 27.5%, with pore sizes concentrated at 95 nm. These findings contribute significantly to our understanding of Qing dynasty tomb construction technologies and provide a solid scientific basis for the restoration of such historical sites.
... As with other examples of ancient concrete of this era, it was used as a floor material in residential structures. Analyses of two different floors (Li, Zhao, and Li 2012), designated F-405 and F-901, has shown that they were made of a lightweight concrete formed by the mixture of calcined ginger nut, red clay and hollow calcined calcareous nodules known as 'kunkur'. Carbon-14 dating of F-405 and F-901 place the age of the floors as 6769 ± 312 and 6137 ± 159 years old, respectively. ...
... Firstly, the β-belite that will have been formed by calcining the ginger nut would have hydrated to form C-S-H and calcium aluminate silicate hydrate (C-A-S-H.). Secondly, additional strength would have developed from the hydration and subsequent carbonation of the CaO from both materials to form CaCO 3 (Li, Zhao, and Li 2012). ...
For thousands of years, mortar-based materials — including bedding mortars, plaster floors, internal wall plasters, external wall renders and stuccos, and concrete — have been key construction materials in many cultures throughout the world. This paper gives an overview and examples of the use and development of mortar-based materials in cultures across the Middle East, Europe, Asia, and Mesoamerica, prior to the development of hydraulic cements in the late 18th and early19th centuries.
... The site is considered one of the most important Neolithic sites in northwest China [2]. Its F901 site is the most prominent palace-style construction with a total area of 420 m 2 , the largest and most highly crafted large-scale housing structure from China's prehistoric era [3,4]. The origin of this structure may be traced back to the late phase of the Yangshao culture, approximately 5000 years ago [5,6]. ...
The Dadiwan F901 site, boasting a history of over 5000 years, stands as the largest and most intricately crafted large-scale housing structure from China’s prehistoric era. The early renovation efforts, incorporating a sealed glass curtain wall, led to a continuous rise in relative humidity within the site, triggering outbreaks of microbial diseases. Subsequent measures successfully restored stability to the thermal and humid environment. This paper employs on-site real-time environmental monitoring and numerical simulation methods to assess the ventilation effectiveness and relative humidity changes before and after multiple interior modifications of the Dadiwan F901 site museum. The results indicate that the fully enclosed glass curtain wall can suppress the dependence of indoor humidity fluctuations on external weather fluctuations but has generated unintended consequences, leading to increased air relative humidity and even reaching saturation in the museum space. The strategic deployment of louvered windows and duct fans proved effective in enhancing internal airflow dynamics and overall air exchange capacity. It was possible to ensure that the relative humidity inside the site remained at approximately 70%, meeting the essential requirements for the preservation of cultural relics. This study is of great significance for alleviating the deterioration problem of enclosed exhibition halls of earthen relics.
Graphical Abstract
... Shell lime is another hydraulic lime calcined from shells, and it was widely used in ancient buildings in southeast China [20]. These three hydraulic limes are found mainly in ancient Chinese buildings and have been researched to restore rock heritages in recent years [21]. ...
Ginger nut, AGA soil, and shell lime are the primary building limes used in traditional Chinese architectural sites. They have been widely researched and developed for restoring rock and soil heritage over the last decade. Previous studies have shown that these materials are compatible with weathered rock in terms of mechanical properties and environmental adaptability. In this study, metakaolinite was added to Chinese hydraulic limes to improve the mortar abilities. The basic properties and weather abilities of the mortars were evaluated. The characteristics of carbonation and hydration were analyzed over 900 days. The results indicated that the early strength improved and the contracting rate reduced when metakaolinite was added. The shell lime mortar was improved considerably compared with the modified ginger nut and AGA soil. The lime mortar content was determined using the X-ray diffraction results. The carbonation and hydration characteristics revealed that the metakaolinite aided the generation of hydraulic products (Ca2Al2SiO7·nH2O and β-CaSiO3·nH2O), particularly in the early stage. The microstructures were observed by scanning electron microscopy, which revealed more uniform and consolidated structures when metakaolinite was added.
... Natural cementing materials such as Glutinous Rice Pulp (GRP) and Calcined Ginger Nuts (CGN) are widely used in earthen sites [20]. The grouting material with CGN as the main agent has good mobility, small shrinkage, high mechanical strength, and good compatibility with soil [21,22]. ...
Grouting material is the core force transfer medium of grouting sealing and anchorage reinforcement methods for cracks in earthen sites; the performance of grouting slurry is the key to affecting the reinforcement effect. To solve the problems of poor flexural strength, easy shrinkage and cracking of existing grouting slurry, using Glutinous Rice Pulp, Calcined Ginger Nuts, and Loess Soil as substrates, and choosing the content and length of basalt fiber (BF) as control variables, 13 groups of specimens were designed by orthogonal test method to explore the influence of mixed fiber on the mobility, shrinkage, compressive, and flexural strength. The microstructure was analyzed by SEM to explain the strengthening mechanism from physical and chemical perspectives. The results show that the mobility decreases linearly with the increase in BF content and length; after mixing BF, the shrinkage rate is significantly reduced, but when the fiber length and content are relatively high, the surface is prone to cracking. The excellent bridging ability of BF can effectively improve the compressive and flexural strength of the specimen. When the fiber length and content are high, the specimen shows certain ductile failure characteristics, and the fracture energy increases more than 10 times.
... In addition to using the same material composition and ratios as the original plaster for restoration to obtain better compatibility, some polymer materials (Su et (Apostolopoulou et al. 2021). CGN is similar to NHL, and it was rst discovered at the Dadiwan site (3000 BC) in China and was obtained by calcining calcareous concretion in loess (Li et al. 2012). ...
Earthen plasters have been widely used in historical buildings, especially in wall paintings in northwest China. However, the properties of earthen plasters have deteriorated dramatically under long-term weathering. In order to investigate one of the key issues in plaster restoration, i.e., whether the plaster can be effectively applied on different substrates, seven compositions of plasters were prepared and applied to three types of substrates modeled after actual wall painting supports. Shrinkage of the plasters was measured and the adhesion of the plasters to the substrates was characterized by a shear test using a designed device. The results show that the shrinkage of the plaster depends on the material composition of the plaster and is almost independent of the type of substrate. The addition of vegetal fibers to earthen plaster can effectively improve interfacial adhesion. The type and the surface roughness of the substrate have a significant effect on the adhesion between the earthen plaster and the substrate.
... In recent years, a kind of ancient building material, ginger nuts, has been in the spotlight because of its mechanics and weatherability performance, cost-effective and environmentally friendly characteristics. Ginger nuts were discovered through scientific research on building materials of relatively complete human residence in the Yangshao period of Dadiwan, Gansu Province [31,32]. Ginger nuts contain 70 %-80 % calcium carbonate, 20 %-30 % clay, and a few other minerals. ...
Earthen site is a kind of preciously historic building constructed with soil as the building material. In northwestern China, the earthen sites are threatened because of environmental hazards, such as wind erosion, water erosion, and so on. Rammed reinforcement of the erosion area can improve the overall stability of the site. In addition, region formed by ramming reinforcement can be defined as ramming area. The formation of the ramming area is a new surface, and new interface between the ramming area and the original site is formed. Therefore, ramming area must meet principle of "repairing the old as the old" and maintain compatibility with the original earthen sites in terms of soil strength, permeability. Calcined ginger nuts is an environment-friendly and inorganic material that is emerging curing agent to reinforce the erosion area of the earthen site, which may make the reinforcement area to meet the above requirements. A series of tests were performed to verify its feasibility and investigate its solidified effects and mechanism. The study demonstrated that, with dosage and curing time increasing, the shear strength and unconfined compressive strength of solidified samples slightly improved and the permeability coefficient decreased with a small extent, the disintegration and shrinkage rate significantly decreased, and the total color difference value of samples increased as the sample became brighter. Furthermore, the mechanism of solidified soil has been studied by performing mercury injection, X-ray diffraction, and scanning electron micrograph tests under 25% dosage, which is proposed as the optimum dosage. The pore size decreased with increase of curing time as calcium carbonate content increased. Crystal type of calcium carbonate is mainly calcite-a material with high strength and cohesiveness. Thus, carbonation is the dominant reaction during the curing stage. Moreover, the crystal morphology of calcite changes from needle-stick calcite to flake. In conclusion, calcined ginger nuts can be used as curing agent for reinforcing the erosion area of earthen sites.
... The main hall of F901 occupies an area of 131 m 2 . The floor of the main hall has an appearance very similar to modern concrete, therefore it was named 'Yangshao cement' (Li et al., 2012;Zhao et al., 2018). Historically in China, monitoring of the soil air was named 'hou-qi', which is using the rise and fall of MASC in the closed system to determine the 24 solar terms for the purpose of guiding agricultural seasons (Li, 2018;2021). ...
... The main hall of F901 occupies an area of 131 m 2 . The floor of the main hall has an appearance very similar to modern concrete, therefore it was named 'Yangshao cement' (Li et al., 2012;Zhao et al., 2018). Historically in China, monitoring of the soil air was named 'hou-qi', which is using the rise and fall of MASC in the closed system to determine the 24 solar terms for the purpose of guiding agricultural seasons (Li, 2018;2021). ...
Monitoring experiments of soil air in column show that relative humidity (RH) of air in the soil of the Loess Plateau fluctuates with atmospheric pressure (AP), which is barometric pumping resulting in the vertical movement of soil air and the change of its RH. When AP increases, soil air is compressed and atmospheric air enters the soil, causing RH to decrease. When AP decreases, soil air expands and rises, causing the flow of moist air outwards from the soil and increasing RH. Therefore, RH fluctuates reversely with AP (the correlation coefficient between RH and AP can reach –0.74). This paper studies the effect of barometric pumping on RH in the loessal soil of the Loess Plateau, and reveals the mechanism responsible for the vertical movement of soil air. On a yearly timescale, the volume of soil air expands with a general decrease in AP from January to July, then compresses with an increase in AP from July to December. On a daily timescale, the air in soil shows bimodal fluctuations. Barometric pumping is the driving force underpinning the soil air movement, and therefore dominating its fundamental characteristics. From a preliminary establishment of model calculation, the volume of soil air movement occurring in the Loess Plateau is proportional to the amplitude of AP fluctuations, aerated porosity, and thickness of the local loess layer. The amplitude of air fluctuations in the soil is independent from the aerated porosity.
... Ginger nut was confirmed as the earliest lightweight concrete in China (Li, Zhao, and Li 2012), after calcining under a specific temperature about 1000°C, calcined ginger nut (CGN) shares similar properties with natural hydraulic lime (NHL). Chen et al. (2017) suggested that 1100°C was the optimal calcination temperature considering that the content of both air hardening and hydraulic products were the maximum, and the CGN can be served as protective materials for earthen sites for its favourable weathering resistance abilities. ...
Calcined ginger nuts (CGN)-based grouts are widely utilized in anchoring conservation of unstable earthen sites in the northwest of China. However, the long-term performance of the anchor system, which is dominated by the durability of anchor grouts in the real environment remains unclear. In this study, durability of CGN admixed with fly ash (F) and quartz sand (S) in the real environment were evaluated regarding physical properties (density, surface hardness, water penetration capacity, and permeability), soluble salts content and micro-structure (SEM). Grouts concretions of CGN admixed with F and S were buried at the feet of Ming Great Wall, Gulang County, Gansu Province, China for six years. The results indicate that two decay patterns including extensive crack formations along specimens’ edges and micro-cracks and materials losses (granular disintegration) on the surface were captured. Moreover, crust structure, which is inferred as carbonation front was detected on the surface of specimens. The performance of the grouts in the real environment is quite different from that in the laboratory, in particular, specimens of CGN admixed with S singly were already broken due to the crack formation. Long-term performance priority of CGN-based grouts is CGN-FS>CGN-F>CGN-S.
... Similar to NHL, a kind of ancient lime-based binder named calcined ginger nut (CGN) was 53 first discovered at the Dadiwan site (3000 BC) in China. Studies have shown that CGN is formed 54 by ginger nut (GN) calcined at 1000 °C for 2 h, and it also has two hardening phases: a hydration 55 phase and a carbonation phase [24, 25]. As the raw material of CGN, GN is common in Northwest 56 ...
In order to study the consolidation mechanism of traditional lime-based binders in the restoration of earthen plaster, the mechanical strength, hydration kinetics, and microstructure properties of calcined ginger nut (CGN)- and natural hydraulic lime (NHL)-based pastes were systematically investigated and compared. The results showed that CGN had good compatibility with clayish earth. Compared with the NHL-based pastes, the CGN-based pastes exhibited a higher late-stage compressive strength, lower heat release, denser microstructure and similar pore size distribution compared to the original plaster.
... (II) Strong alkaline environment The ionization of calcium hydroxide (Ca(OH) 2 ) generates hydroxyl ions (OH ) (eq. (2)) [16], which provide a strong alkaline environment with a typical pH value as high as 12.4 [17]. 2 2 Ca(OH) CO 2OH (pH=12.4) ...
Water stability of soil is crucial to the durability of earthen monuments, especially those located in the humid weather condition. This paper discusses the selection reason of materials (tung oil and quicklime) for earthen monument treatment, and then validates the applicability of these materials with tests of soil-water characteristic curve (SWCC), aggregate stability test (AST) and scanning electron microscope (SEM). The soil tested was sampled from Da Bao’en temple in Nanjing, Jiangsu province, China. The test results indicate that the carbonation reaction of quicklime offers a favorable environment for the formation of tung oil film. Meanwhile, the regulatory function of tung oil restricts the crystallinity of calcium carbonate (CaCO3) and forms fine crystals. Soil treated with both of tung oil and quicklime has good water repellency and aggregate stability without obvious changing in aesthetic appearance. Hydrophobicity and carbonation treatment can be applied prospectively in the conservation of earthen monument located in humid weather condition.
Earthen sites are a kind of constructure with significant historical and cultural value. However, the destruction of earthen sites caused by erosion occurs frequently. The solidification of calcined ginger nuts can improve the strength of the soil so that it can be used to protect the earthen sites. However, the strength degradation of solidified soil by calcined ginger nuts after dry–wet and freeze–thaw cycles is unclear. To reveal the deterioration pattern of solidified soil strength, the effects of its dosage and cycle number on the strength of solidified soil were analyzed through shear strength, dry–wet cycle, and freeze–thaw cycle tests. The results showed that the solidified soil strength decreased first and increased with dosage increase. With the number of dry–wet cycles increasing, the strength of the plain loess decreased rapidly and gradually turned flat. The strength loss of solidified soil was small in the dry–wet process. With freeze–thaw cycle numbers increasing, the strength of the plain loess decreased first and then tended to be flat, the strength of solidified soil decreased first and then increased slightly, and the change in the strength had a clear inflection point. With the increasing dosage, freeze–thaw cycle numbers corresponding to the inflection point were significantly reduced. These results indicate that calcined ginger nuts could enhance the resistance of earthen sites loess to dry–wet and freeze–thaw cycles.
This paper presents an experimental study on the mechanical properties of grout–soil interfaces under different grout proportions and interface forms in conservation engineering of rammed earthen sites. Calcined ginger nut (CGN) admixed with fly ash (F) and quartz sand (Q) is selected as the grouting material. Physical models of grout–soil interfaces in three groups of grouts (each group has five proportions) and different wall roughness of hole (smooth and threaded) have been made. The mechanical properties of the models including load–displacement curves and shear strength of different interfaces are obtained by an indoor push-out test system. The failure processes from interfacial shear deformation to shear dislocation are analyzed. The shear strength increases with the wall roughness of the anchor hole under the same grouting materials. Mix proportion of F (70%) exhibits the highest interfacial shear strength and mix proportion of Q (70%) gets the lowest strength. The smooth-hole wall presents the interfacial shear failure of the grout–soil, and failure in the threaded hole wall mainly shears off the soil. The three statistical models show the stress–strain relationship at the interfacial shear deformation stage. The study provides a scientific basis for the mechanical properties of the grout–soil interface and the grouting optimization of anchorage engineering in earthen sites.
Calcined ginger nuts admixed by fly ash and quartz sand (CGN-(F+S)) has been validated to be basically compatible to earthen sites as an anchor grout. Accelerated ageing tests including water stability test, temperature and humidity cycling test, soundness test and alkali resistance test are conducted with the objective to further research the property changes of CGN-(F+S) grout. Density, surface hardness, water penetration capacity, water permeability capacity, soluble salt, scanning electron microscopy (SEM) images and energy dispersive spectrometry (EDS) spectrum of these samples have been tested after accelerated ageing tests. The results show that densities of samples decrease, surface hardness, water penetration capacity and water permeability capacity of samples increase generally. Besides, soluble salt analysis, SEM and EDS results well corroborate the changes. Based on the results it can be concluded that property changes are most serious after temperature and humidity cycling test, followed by water stability, soundness and alkali resistance test in sequence. But in general, CGN-(F+S) still has good durability.
Calcined ginger nut (CGN) has been applied in grouting mortars for anchoring unstable earthen sites, but the lack of scientific research limits its application. In this study, CGN-based grouts admixed with fly ash (F), quartz sand (S), or both are evaluated. To explore the optimal mixture ratios, three types of mixing groups (five proportion gradients in each group) are established. All the grout specimens are buried and maintained outdoors, and their physical (shrinkage rate, density, elastic wave velocity, and permeability) and mechanical properties are continuously examined over 180 days. The solidification processes at different ages are simultaneously observed by means of scanning electron microscopy (SEM) images. The results indicate that the physical properties of grouts are influenced significantly by initial moisture content but then remain steady for approximately 15 days. Quartz sand can effectively reduce the shrinkage rate of grouts as well as adjust their density and permeability, and might be considered as an ideal mixing material for CGN. In the solidification process, grouts are rapidly solidified after the initial hydration reaction, and the carbonation reaction in the later stage constantly improves their mechanical strength, with physical properties kept relatively stable. SEM images show fly ash and quartz sand particles are cemented by CaCO3 crystals. Through comprehensive comparison, the grouts with the mass ratio of CGN and S at 1:1 are found to better satisfy requirements that grouts should be compatible with earthen sites.
The detailed kinematic pattern of the Ordos block, North China and its surrounding rift systems remains uncertain, mainly due to the low signal-to-noise ratio of the Global Positioning System (GPS) velocity data and the lack of GPS stations in this region. In this study, we have obtained a new and dense velocity field by processing GPS data primarily collected from the Crustal Motion Observation Network of China and from other GPS networks between 1998 and 2014. The GPS velocities within the Ordos block can be interpreted as counterclockwise rotation of the block about the Euler pole with respect to the Eurasia plate. Velocity profiles across the graben-bounding faults show relatively rapid right-lateral strike-slip motion along the Yinchuan graben, with a rate of 0.8 2.6 mm/a from north to south. In addition, a right-lateral slip rate of 1.1 1.6 mm/a is estimated along the central segment of the Shanxi rift. However, strike-slip motion is not detected along the northern and southern margins of the Ordos block. Conversely, significant extension motion is detected across the northwestern corner of the block, with a value of 1.6 mm/a, and along the northern segment of the Shanxi rift, where an extensional rate of 1.3 1.7 mm/a is measured. Both the Daihai and Datong basins are experiencing crustal extension. On the southwestern margin of the block, deformation across the compressional zone of the Liupanshan range is subtle; however, the far-field shorting rate is as high as 3.0 mm/a, implying that this region is experiencing ongoing compression. The results reveal that present-day fault slip occurs mainly along the block bounding faults, with the exception of faults along the northern and southern margins of the block. These results provide new insights into the nature of tectonic deformation around the Ordos block, and are useful for assessing the seismic activity in this region.
physical model and field experiments which consists of pullout test and strain monitoring on bolt-grout interface were conducted on wood bolts fully grouted by natural hydraulic lime and quartz sand slurry in rammed earth to study anchor capacity, failure mode, shear stress distribution and transfer along the bolt-grout interface. were studied on its Experimental results shows that ultimate anchor force in laboratory (30 kN~45 kN) is larger than that in field (16.2 kN~19 kN). Anchor system has strong ductility. In the process of loading, single-peak or double-peak stress distributes along bolt-grout interface and interfacial stress transfers toward anchor end, meanwhile, compressive stress mainly emerges at middle-end of anchor segment. With considerably physical and mechanical compatibility to rammed earth, the anchor system is suitable to conserve rammed earth heritages. ©, 2015, Tumu Jianzhu yu Huanjing Gongcheng/Journal of Civil, Architectural and Environmental Engineering. All right reserved.
This study focuses on resolving moderate amounts of crustal motion at the continental scale based on a large volume of global positioning system (GPS) data during 1998–2014. A state-of-the-art GPS processing strategy was used to resolve position time series and velocities from carrier beat phases for all available data. Position time series were closely analyzed to estimate linear constant, coseismic displacements, postseismic motions, and other parameters. We present coseismic offsets inferred from the GPS data for the 2010 Yushu and 2014 Yutian earthquakes, and also illustrate transient postseismic motions following the 2001 Kokoxili, 2008 Wenchuan, and 2011 Tohoku-Oki earthquakes. Since not all GPS position time series dominated by postseismic motions can be modeled and corrected reasonably, we present contemporary horizontal velocities from 2009 to 2014 for campaign stations and from 1998 to 2014 for continuous stations, irrespective of postseismic deformations. Our study concludes that we need to accumulate observations over a greater duration and apply accurate postseismic modeling to correct for transient displacement in order to resolve reasonable interseismic velocity.
In this study, calcined ginger nuts (CGN) grouts admixed by fly ash (F) and quartz sand (S) was investigated on its suitability for anchoring use in earthen sites. According to requirement for the consistency of grout, the mix proportions were determined with 0.45 for CGN_F, 0.33 for CGN_S and 0.35 for CGN_F_S, by mass, to study their physical and mechanical property and durability. Test results indicated that use of fly ash can prolong the initial setting time of grout and admixture by fly ash and quartz sand leaded to lowest density and shrinkage, higher porosity, and highest strength. Accelerated aging tests indicated that admixture by fly ash led to a high resistance to fluctuation of temperature and humidity, sulfate attack and alkali environment; meanwhile, admixture by quartz sand resulted in high resistance to freeze-thaw action and water environment. As a compromise, CGN_F_S can get predominant durability. The paper shows that CGN_F_S grout is basically compatible to earthen sites and suitable for anchoring use in the conservation of earthen sites in terms of workability and durability.
Concrete, the most widely used construction material, is evolving. Modern concrete is more than simply a mixture of cement, water, and aggregates; modern concrete contains more and more often mineral components, chemical admixtures, fibres, etc. Of course the utility market will stay the major market of concrete but niche markets implying the use of “à la carte” smart concretes will also develop. The development of these smart concretes results from the emergence of a new science of concrete, a new science of admixtures and the use of sophisticated scientific apparatus to observe concrete microstructure and even nanostructure.
Most ancient concrete in the world
- Z Li
Standard for Test Method of Mechanical Properties on Ordinary Concrete
- Construction Dept
Beijing: China Com-munications Press, 2004 13 Construction Dept. of PRC. Standard for Test Method of Mechanical Properties on Ordinary Concrete When was man-made lime calcinations started? 14 C could date
- X X Wu
- Concrete
Wu X X. Concrete NDT Manual (in Chinese). Beijing: China Com-munications Press, 2004 13 Construction Dept. of PRC. Standard for Test Method of Mechanical Properties on Ordinary Concrete. GB/T 50081-2002, 2003 14 Qiu S H. When was man-made lime calcinations started? 14 C could date (in Chinese). Cult Rel Arch, 1980, 5: 126–130
Review: Cements of yesterday and today, tomorrow of concrete
- P Aïtcin
- P. C. Aïtcin
Aϊtcin P C. Review: Cements of yesterday and today, tomorrow of concrete. Cem Concr Res, 2000, 30: 1349–1359
of Archaeology Discipline of History Depart-ment of Beijing University. Reliability of C-14 sample of limestone region and period issue of Zhenpiyan Site (in Chinese)
- C Laboratory
14 C Laboratory, etc., of Archaeology Discipline of History Depart-ment of Beijing University. Reliability of C-14 sample of limestone region and period issue of Zhenpiyan Site (in Chinese). J Arch, 1982, (2): 243–250
Dadiwan site and their cultural location (in Chinese)
- C B An
- F H Chen
- C. B. An
Crystal Optics (in Chinese)
- D Li
- D. H. Li
Status quo and method of quantitative study on soil structure (in Chinese)
- J L Qi
- D Y Xie
- Y C Shi
Phase analysis of clay minerals by X-Ray diffraction (in Chinese). Rock Mine Anal
- Q Wu
Quantitative analytic method and experiments of X-ray diffraction phase of clay minerals (in Chinese)
- R K Zhang
- G Fan
The use and effectiveness of dispersed hydrated lime in the conservation of monuments and historic structures. In: International Building Lime Symposium Preprints: Contemporary and Historic Uses of Lime in Mortars, Plasters and Stuccos
- P Miller
- M Rabinowitz
- J Sembrat
What on earth was white lime face made from? (in Chinese)
- J Hu
Simply developed history of Portland cement concrete
- X Li
The use and effectiveness of dispersed hydrated lime in the conservation of monuments and historic structures
- P. Miller
20th Century 100 Archaeological Discoveries in China (in Chinese)
- Newsroom of Archeology Journal
A study of micro-structure of soil applied SEM (in Chinese)
- M Zhang
- M. Y. Zhang
The use and effectiveness of dispersed hydrated lime in the conservation of monuments and historic structures
- P Miller
- M Rabinowitz
- J Sembrat
- P. Miller
Simply developed history of Portland cement concrete (in Chinese)
- X Li
- X. Y. Li
Wonderwork of ancient building history of China (in Chinese)
- Z Li
Report on the Chinese sucrose charcoal standard for 14C dating (in Chinese)
- S H Qiu
- L Z Cai
- T M Chen
- S. H. Qiu