Investigations on the Swelling-Shrinkage Behavior of Expansive Soil with Stone Chips Incorporation

Abstract The study of raw materials used for making stone tools allows archaeologists to gain insight into the behaviours of ancient people. Raw materials possess different properties, which influence the ability of knappers to flake, shape and use a stone tool. Measuring these properties experimentally requires specialised laboratories and measuring processes that are not straightforward. This makes such analyses a cost-intensive and often inaccessible way to investigate the past. Here, we present an alternative way to evaluate two mechanical properties, stiffness and hardness, using a single indentation test. We also test whether these two isolated measures allow making predictions on raw material selection and tool shape. We analysed tool-stones from the Middle Stone Age site Sibhudu on South Africa’s eastern seaboard. The site has yielded a rich assemblage of tools from different raw materials. We found that a single indentation test allows measuring hardness and stiffness reliably, simplifying the measurement protocol of raw material studies. We also observed weak correlations between those isolated properties and the shape of the finished tools. This has implications for future studies of Stone Age raw materials, proposing a simplified testing protocol. We also discuss the role of stiffness in stone knapping.

Urbanization, industry, and population growth raise energy consumption. Building construction and energy usage will rise with population expansion. Most buildings gain/loss heat through windows, ceilings, floors, and walls. This section covers roof and wall heat loss. Reducing the energy consumption of buildings could preserve energy savings. Energy uses include industrial, household, transportation, and agricultural. Heat losses in the building envelope result in energy loss. Insulators are essential for energy conservation. This work uses hollow concrete blocks and reinforced cement concrete (RCC) made of stone chips for walls and roof materials to identify effective insulation for building envelopes in Bangladesh. Commonly available and low-cost insulation Expanded polystyrene (EPS) is used to insulate the envelopes. The thermal resistance of the envelopes with EPS insulation was measured using an experimental technique. A model building's heat transfer and energy utilization are calculated using DesignBuilder software for Khulna's meteorological data. This program uses EnergyPlus as an energy simulation engine. The envelope U-value is calculated with and without EPS using Hukseflux sensors. In this research, hollow concrete block walls have 0.14 m2.K/W and stone chip blocks have 0.17 m2.K/W heat resistance. However, plywood-coated EPS insulators have approximately 2 m2.K/W thermal resistance. Insulation saves 96.47% of the energy used for heating in the winter and 56.13% of the energy used for cooling in the summer. So, the addition of EPS insulation in the model building may reduce 56.57% of the energy consumption required for heating and cooling.

ABSTRACT This study examines lithic assemblages recovered from stele sites dating to the last two millennia in the Gedeo Zone of southern Ethiopia. 1,145 artifacts were collected through systematic test excavations and surface surveys at four sites. Using a techno-morphological framework, we analyze the composition, distribution, and technological characteristics of the assemblage. The study highlights the diversification of lithic tools and the dominance of blades and scrapers in later periods which are associated with temporal and functional changes. Additionally, the presence of bipolar reduction and cortex on some tools suggests multiple stages of lithic reduction and conservative resource use due to limited access to raw materials. Comparison of these assemblages across the region provides insights into broader patterns of lithic technology during the Late Holocene.

The beginning of the Upper Paleolithic represents a key period in human history. At this time, we can grasp the technological concepts that Homo sapiens used in the early Upper Paleolithic. The age of the Aurignacian in combination with the three-dimensional ivory artworks, musical instruments and personal ornaments in the Swabian Jura sites emphasize the importance of this region for understanding and defining the Upper Paleolithic. During that time blade and bladelet production became the central interest of lithic production. The study of these lithic reduction sequences is essential for understanding technological inventions and socio-economic behaviors of early anatomically modern humans in Central Europe. So far, however, the lithic technology from the Aurignacian of the Swabian Jura has only been studied in detail at the site of Geißenklösterle. In this paper, we provide an exhaustive study based on the rich lithic assemblage from Vogelherd Cave combining both the chaîne opératoire approach and attribute analysis. This work highlights the importance of carefully sorting minimal raw material units and engaging in systematic refitting. These observations allow us to reconstruct entire reduction sequences including the biographies of both cores and tools. The source and physical characteristics of lithic raw materials greatly influenced decision-making during the reduction process. As in many other Paleolithic contexts, Aurignacian knappers thoroughly exploited imported raw materials while exhausting low quality local material to a lesser degree. Comparisons with other assemblages from the region help to facilitate the characterization of the Swabian Aurignacian. This comparison allows us to separate regional adaptations from more site-specific behaviors.

The article presents the results of laboratory tests of driven piles with static load, the near-pile space of which has been improved by crushed stone and glass chips. The model piles were driven into an array of crushed stone or glass chips, which were placed in pre-drilled wells of different diameters. The purpose of the laboratory studies was to increase the bearing capacity of the driven pile due to the improved near-pile space, which was compared with the same bearing capacity of the pile, but only without improving the near-pile space. The obtained research results have shown the effectiveness of improving the surrounding pile space, which makes it possible to increase the bearing capacity of the driven pile in foundations with low numerical indicators of physical and mechanical characteristics. In addition to increasing the bearing capacity of the driven piles, the issue of recycling glass waste is being addressed, and consequently improving the environmental situation of the environment.

Automated evaluation of stone chip resistance in automotive coatings

Lithic miniaturization in South China since the terminal Pleistocene: A multivariate analysis of lithic reduction from Fodongdi, Fulin and Xiqiaoshan

The Marine Isotope Stage 5 (∼105ka) lithic assemblage from Ga-Mohana Hill North Rockshelter and insights into social transmission across the Kalahari Basin and its environs.

Effect of Jute Fiber Content on Compressive and Split Tensile Strength of Concrete Utilizing Stone Chips as Coarse Aggregates

Controllable and scalable preparation of green nucleation seeding accelerator for cement with inert waste stone chips: Role of amorphization

Retempering concrete is a common practice in the construction industry to restore its workability and compressive strength, despite the recommendation that concrete should be cast immediately after mixing with water. Casting delay significantly affects the concrete compressive strength and workability. This study aims to observe the effects of water and cement retempering on delayed casted concrete for up to 4 hours by measuring concrete compressive strength after 28 days of curing. Three variables; 1) retempering with water (RW), 2) 1st retempering with a small amount of water and cement (RWC1), and 3) 2nd retempering with a larger amount of water and cement (RWC2) were considered. Three concrete types having different coarse aggregates (crushed stone, uncrushed-round stone, and brick chips) were used. The results indicate that the compressive strength of crushed stone, single stone, and brick chip concrete was decreased after retempering with water (RW). Retempering with water and cement in different doses (RWC1 & RWC2) increased the compressive strength of the concrete. A regression model was used to quantify the needed cement (Kg/m3). Equations relating to casting delay and cement (Kg/m3) were also developed to gain the initial concrete compressive strength.

The Peopling of Uzbekistan by Homo sapiens Denisovan

Abstract The use of stone hammers to produce sharp stone flakes—knapping—is thought to represent a significant stage in hominin technological evolution because it facilitated the exploitation of novel resources, including meat obtained from medium‐to‐large‐sized vertebrates. The invention of knapping may have occurred via an additive (i.e., cumulative) process that combined several innovative stages. Here, we propose that one of these stages was the hominin use of ‘naturaliths,’ which we define as naturally produced sharp stone fragments that could be used as cutting tools. Based on a review of the literature and our own research, we first suggest that the ‘typical’ view, namely that sharp‐edged stones are seldom produced by nonprimate processes, is likely incorrect. Instead, naturaliths can be, and are being, endlessly produced in a wide range of settings and thus may occur on the landscape in far greater numbers than archaeologists currently understand or acknowledge. We then explore the potential role this ‘naturalith prevalence’ may have played in the origin of hominin stone knapping. Our hypothesis suggests that the origin of knapping was not a ‘Eureka!’ moment whereby hominins first made a sharp flake by intention or by accident and then sought something to cut, but instead was an emulative process by hominins aiming to reproduce the sharp tools furnished by mother nature and already in demand. We conclude with a discussion of several corollaries our proposal prompts, and several avenues of future research that can support or question our proposal.

Sedentism is an adaptive alternative in human societies which is often associated with the emergence of complex societies in the Holocene. To elucidate the factors and processes of the emergence of sedentary societies, continuous accumulation of case studies based on robust evidence from across the world is required. Given abundant archaeological and geological evidence from the late Pleistocene to early Holocene, Tanegashima Island, situated in the southern Japanese Archipelago of the northwestern Pacific Rim, has significant potential to unravel factors and processes of sedentism. Our study evaluates long-term change in hunter-gatherer mobility on Tanegashima Island from the Upper Paleolithic to Incipient Jomon (ca.36,000–12,800 cal BP). Based on Bayesian age modelling, we performed diachronic analyses on lithic toolkit structure, lithic reduction technology, lithic raw material composition, and occupation intensity. The results illustrate that settlement-subsistence strategies on Tanegashima primarily correspond to the change in environmental conditions, mainly food resources, and foragers increased their degrees of sedentism when abundant forest existed. More important is that highly stable sedentism, which is not observed until the Incipient Jomon, depends not only on such a productive environment, but also on the increase in population size. High occupation intensity during the Incipient Jomon on the island is likely attributed to an influx of people from Kyushu proper. Although the relationship between cause and effect of these factors is still to be clarified in future work, our study provides insights on the fundamental causes of sedentism in the temperate forest of the late Pleistocene.

The Middle Stone Age (MSA) of southern Africa is mainly known from rock shelters and caves. How early modern humans interacted with their landscapes remains comparatively understudied. The site of Jojosi 1, situated north of Nquthu in north central KwaZulu-Natal, is set within erosional badlands known locally as ‘dongas’. This locality offers a rare opportunity to study MSA technology and settlement dynamics in an open-air context. G. Botha initially discovered Jojosi 1 in 1991. He brought it to A. Mazel’s attention who excavated the site in the same year, but did not publish the lithic assemblage. Here, we report on the site’s rediscovery coupled with the first lithic analysis and luminescence dating. This work provides insights into the site formation processes of Jojosi 1 and lithic reduction strategies, raw material provisioning, and landscape use. Our techno-typological analysis draws upon Mazel’s collection of 7529 artefacts, combining attribute analysis and refitting studies. The results show the exclusive use of hornfels and its reduction via platform cores and Levallois methods to produce flakes and blades. Retouched tools are scarce and comprise mostly notched or denticulate pieces but lack backed tools, unifacial, and bifacial points. The museum collection features abundant small debitage and a strong component of cortical, initial stage, and core preparation flakes. The 48 refitted artefacts and ample small debitage in a spatially constricted band suggest high assemblage integrity with minimal post-depositional disturbance. Infrared stimulated luminescence dating of coarse grain feldspars brackets the archaeological occurrence to ~ 139–106 ka. Comparisons with contemporary lithic assemblages link the assemblage to the early MSA in southern Africa. We interpret Jojosi 1 as a knapping event aimed at blank production and exploitation of local high-quality hornfels. With little evidence for other behaviours, the site likely reflects a short-term knapping workshop on a source of abundant hornfels slabs. Our ongoing excavations in the Jojosi Dongas will be able to test this hypothesis and will work to characterise the technological adaptations and settlement dynamics of the MSA hunter-gatherers in this area.

Lithic artefacts provide the principal means to study cultural change in the deep human past. Tools and cores have been the focus of much prior research based on their perceived information content and cultural relevance. Unretouched flakes rarely attract comparable attention in archaeological studies, despite being the most abundant assemblage elements and featuring prominently in ethnographic and experimental work. Here, we examine the potential of flake morphology for tracing cultural change utilising 4,512 flakes, each characterised by 16 standard mixed-scale attributes, from a well-documented cultural sequence at the Middle Stone Age site of Sibhudu, South Africa. We quantified multivariate similarities among flakes using FLEXDIST, a highly versatile method capable of handling mixed, correlated, incomplete, and high-dimensional data. Our findings reveal a significant gradual change in flake morphology that aligns with the documented cultural succession at Sibhudu. Furthermore, our analysis provides new insights into the patterning of variability throughout the studied sequence. The demonstrated potential of flakes to track cultural change opens up additional avenues for comparative research due to their ubiquity, the availability of commonly recorded attributes, and especially in the absence of cores or tools. FLEXDIST, with its versatile applicability to complex lithic datasets, holds particular promise in this regard.

Abstract In the present discussion, I will focus on the creation of baby warriors in Mesoamerica in a twofold manner: as human beings and as blade stones. The emphasis will be on central Mexico, complemented with essential data from other parts of Postclassic Mesoamerica. By juxtaposing information from historical sources in a novel way, this investigation seeks to offer new insights that should reinforce the idea that warriors captured on the battlefield were considered to be children. Although this idea has been suggested before, this article aims to contribute new historical evidence that not only confirms this notion but also widens our understanding of the creation of nonbiological offspring. Making kin out of Others aims to satisfy a cosmological need to incorporate vital energy and elements for individual and collective personhood from outside of the community. The second idea of this investigation focuses on a related productive variant of this gestational dynamic, suggesting that by stone flaking and chipping, children (of stone) were fabricated. Some of them were indeed “child blade stones” who personified warriors and fed themselves with sacrificial victims, securing sustenance for the hungry gods. I argue that the birth of these warriors should be integrated into a major mythological theme—namely, the Child Hero and the Old Adoptive Mother.

The article provides a spatial analysis of Archaeological Horizon 2 (AH2) at the Tolbor-21 site, containing rare evidence of human presence in Northern Mongolia during the climatic change era associated with the Last Glacial Maximum. The collection from this horizon serves as a source for reconstructing the characteristics of lithic industry of the final Early Upper Paleolithic (EUP). The enclosing lithological layer has undergone significant post-sedimentary deformation and, across most of investigated area, is subdivided into two parts lying within different lithological strata. This study involved individually recorded finds from AH2 divided into the upper (2A) and lower (2B) horizons, followed by a comparative spatial analysis. The aim was to assess the preservation state of horizons and to reconstruct spatial organization of the site by the bearers of the final EUP industry. Distribution of finds in the upper horizon (AH2A) indicates that the original anthropogenic structure has been disrupted, and the observed patterns (elongated clusters, weak correlation between most find categories) are related to natural processes. The lower horizon (AH2B) retained traces of the original spatial organization: cores, tools and flakes co-occur in cluster, and the spatial correlation between cores and tools was revealed. It is concluded that AH2 represents a single cultural and chronological unit that was separated into two strata due to post-sedimentary processes. Its less disturbed lower part (AH2B) indicates the absence of spatial zoning for different types of activities (lithic reduction and tool use) and can serve for reconstructing settlement activity of bearers of the final EUP in Northern Mongolia.

The lithic industry of the Itapeva refuge, located southeast of SP, Brazil, was examined. The physical and technical attributes were checked on 3,168 pieces with the aim of creating groupings and statistically verifying their relevance from the point of view of the intersection between them. The study focuses on knapping and the quality of the raw material to determine the supposed little technical transformation of the lithic supports used. The conclusion is that there are knapping processes that can be detected through statistical analyzes of knapping sequences considered short and random, suggesting the hypothesis that lithic industries called expedients have standardized reduction that are connected to a series of knapping methods in raw materials of variable quality, with no drop in technical execution based on random knapping.