Floor Mortar Research Articles

Application of Novel Phase Change Material Constructive Solution for Thermal Regulation of Passive Solar Buildings

A comprehensive investigation regarding the hygrothermal behavior of a constructive solution containing phase change materials (PCMs) was performed on a full-scale test cell, divided into two similar compartments. This involved hygrothermal monitoring (indoor air temperature) of the two compartments, in which one had PCM incorporated into the floor mortar. The main goal of this research was to investigate the potential of this kind of solution for overheating mitigation. The numerical study was conducted using EnergyPlus® software (version 9.0), exploring different natural ventilation flow rates to gauge the novel solution’s potential to reduce overheating rates. The results from the monitoring studies revealed prolonged periods of thermal discomfort in both test cells, particularly overheating. However, it was proven that the PCM application in one of the test cells led to a reduction of almost 10 °C in the maximum peak of air temperature. In the simulation analysis, the increase in the ventilation rate led to a linear decrease in the overheating hours of up to one renovation per hour, and then the reductions were attenuated.

Comparative life cycle assessment of traditional timber jack arch slab refurbishment solutions: Eco-efficient proposal versus conventional ones

Abstract Purpose In the context of worldwide efforts to reduce plastic waste, the authors of this document patented a cement mortar floor slab interjoist prefab vault incorporating recycled plastic. This piece was designed to be used for the refurbishment of Spanish traditional timber jack arch floor slabs. Taking into account nowadays context, it is essential to assess the environmental benefits of this product. Methods A cradle to gate LCA has been performed following ISO 14044 and ISO 15804 recommendations. Thus, the aim of this research is both to provide a measure of the environmental improvement that this material adds to the building process and to compare it with current most used construction elements used for the same function. It is stressed that this study is based mainly on primary data obtained from Spanish producers. Results The results obtained show that the reference scenario, corresponding to the new patented vault, is the system with lower impacts in six out of the seven categories assessed. Furthermore, when adding the LCA normalisation step, the conducted analysis show that for the most influential impact categories, GWP100a and AD fossil fuels, the reference scenario bears the lowest scores. Conclusions It can be concluded that the new patented vault has a better environmental performance than the assessed commercial vaults. Therefore, in this research, the benefits for the construction sector to incorporate recycled plastics are shown. Furthermore, these results can encourage the research on construction products that include recycled plastics in their composition. Bearing in mind that this study assesses the impacts corresponding to the production of a prototype of the newly vault, it is considered that there is room for further improvement through the optimisation of the production process.

Early settlement construction in Southeast Asia: lime mortar floor sequences at Loc Giang, southern Vietnam

Research on prehistoric mainland Southeast Asia is dominated by mortuary contexts, leaving processes such as the transition to sedentism relatively understudied. Recent excavations in southern Vietnam, however, have recovered new evidence for settlement. The authors report on investigations at the neolithic site of Loc Giang (3980–3270 cal BP) in southern Vietnam, where excavation revealed a vertical sequence of more than 30 surfaces. Microarchaeological analyses indicate that these features are carefully prepared lime mortar floors; the lime was probably produced from burnt shell. The floors date to between 3510 and 3150 cal BP, providing the earliest-known evidence for the use of lime mortar, and for durable settlement construction, in this region.

Archaeological and Chemical Investigation on the High Imperial Mosaic Floor Mortars of the Domus Integrated in the Museum of Archaeology D. Diogo de Sousa, Braga, Portugal

This paper intends to characterize the floor mortar layers (nucleus, rudus and statumen) of the high imperial mosaics of the domus integrated in the Museum of Archeology D. Diogo de Sousa, the oldest roman housing testimonies known in Braga, Portugal. It offers an important archaeological and historical contextualization and first chemical characterization attempt on the mortars. The study of 13 mortar samples was carried out at a chemical level through X-ray fluorescence spectroscopy (XRF). All samples presented low lime content when compared to similar studies. A high chemical similarity between nucleus mortars (opus signinum) and chemical composition differences between rudus and statumen mortars was determined, confirmed by statistical analyses. Their composition was distinctly related to the stratigraphic position of each floor mortar layer, following Vitruvius’ model, and to the external conditions and treatments (e.g., capillary rise with soluble salts and application of chemical treatments), to which they were submitted.

Influence of Redispersible Powder on Properties of Self-Leveling Mortar of Ternary Cementitious System.

The self-leveling mortar (SLM) of a ternary cementitious system with different dosages of redispersible powder (RP) with ordinary Portland cement (OPC), sulfoaluminate cement (SAC), and calcium sulfate (CS) as cementitious materials was investigated with regard to fluidity, bond strength, shrinkage rate, abrasion resistance, flexural strength, and compressive strength. The performance parameters obtained from the experimental test for SLM were weighted values calculated with an analytic hierarchy process (AHP). The comprehensive index of performance was evaluated on the basis of a weighted-sum method, and the optimal dosage of RP was determined according to the comprehensive index. The experimental results demonstrated that the fluidity of SLM decreased with the increase in RP dosage at the beginning but then increased thereafter and decreased rapidly as the dosage went beyond 3.0%. The addition of RP resulted in a significant improvement in bond strength (of SLM), reduction in the shrinkage rate, abrasion loss, early flexural strength and compressive strength, and resistance to cracking. The properties of SLM with 3.0% RP can meet the requirements of the industrial standard for cementitious self-leveling floor mortar. Compared with the SLM without RP, the bond strength of SLM with 3.0% RP was increased by 46.7%, while the shrinkage rate and abrasion loss were reduced by 50% and 71.9% respectively. The weighted values of fluidity, compressive strength, flexural strength, stability, cohesiveness, and abrasion resistance were 0.422, 0.196, 0.196, 0.089, 0.058, and 0.039, respectively. A higher value of the comprehensive index generally denotes a better performance. The comprehensive index of SLM with 3.0% RP was the highest.

A study of the physical properties and chemical reagents of epoxy mortar floor intermediate coating using recycled glass sand as filler

The purpose of this paper is to investigate the feasibility of using recycled glass sand as filler for epoxy mortar floor intermediate coating. Four physical properties and 10 chemical reagents are studied. The particle size of recycled glass sand and the type of hardening agent are two important factors that may influence these physical properties and chemical reagents. Thus, an L9 orthogonal array is used for the experiments. The optimum factor level combination is found by minimizing the total quality loses of these physical properties and chemical reagents. The results show that the optimum factor level combination meets all the specifications of these physical properties and chemical reagents. Thus, recycled glass sand can be reused as filler for epoxy mortar floor intermediate coating. Therefore, the goal of saving energy, reducing carbon consumption and producing green building material can be achieved.

A Study on the Formulation Selection of Self Leveling Floor Mortar with Fluidity and Early Strength Improvements

A Study on the Formulation Selection of Self Leveling Floor Mortar with Fluidity and Early Strength Improvements

Recent Development and Application of Polymers in Concrete Technology in Singapore

Polymer has been extensively used in construction in Singapore during the past few decades and has become a necessary component of some building materials including polymer modified cement mortar, epoxy or Polyurethane (PU) floor screed and injection materials, and fiber-reinforced plastic (FRP) materials. Compare with conventional concrete, polymer concrete composites may achieve remarkable advantages, such as high tension, high flexural strength, high ductility, ability to absorb energy, and high resistance to chemical attack, corrosion, freezing and thawing, and consequently gain more research interest for the scientific community. There are numerous possibilities for incorporation of these materials, such as latex, natural resources, fibers, nanomaterials and laminates. The presence of polymer makes it suitable for wide applications. The various categories of polymer concrete composites are widely used in Singapore’s public and private projects. To ensure and maintain the high standards of the building quality, independent testing and inspection plays a very important role. The present paper reviews recent research and development activities, and applications of polymer concrete composites in Singapore. The innovations and new approaches are reviewed. The development of the requirements and specifications for various polymer concrete composite products are described and discussed. The effect of different factors on the polymer concrete composite and material selection are also described. In addition, the paper also outlines the methods and measures used to inspect and control the quality of application.

알파반수석고를 활용한 비소성결합재 기반 바닥 모르타르의 경화특성 및 건조수축 평가

Floor mortar experiences dry shrinkage by temperature and humidity difference of internal matrix with material type. Also, since floor mortar is influenced by environmental conditions during placing and curing period, cracks are likely to be occurred. In this study, it was evaluated the hardening and dry shrinkage properties of non-sintered binder based floor mortar utilizing alpha-hemihydrate gypsum which has expansibility in order to prevent crack of the floor mortar. It was applied to the construction site, and examined the effects of external environmental conditions on shrinkage deformation and cracking. Different types of slag accelerated initial and final setting in comparison with cement mortar and its compressive strength was satisfied standard compressive strength for floor mortar. Also shrinkage deformation behavior after the initial expansion exhibited a similar tendency with the cement mortar. From the field application result, no crack was found from slag mortar, and it is determined that the slag mortar has better dimensional stability than cement mortar caused by external environment conditions.

Review on Application of Polymer Concrete in Singapore

Singapore is a small island country, but has won renown as uncorrupted government and high quality products. Independent testing and inspection played a very important role for this achievement[1]. The Housing and Development Board (HDB) is the sole public authority in Singapore and was set up as a statutory on 1 February 1960. Within 45 years, it built more than 700,000 flats housing approximately 86% of the population. Every year, around 40,000 new flats (about 400 blocks) are built up to meet the demands. In March 1992, HDB launched the 15-year main upgrading programme (MUP) to vying the finishes and facilities of old estates up to the standard of those in the new towns. The upgrading programme is a conscious effort by the government to provide a better living environment, strengthen existing community ties and enhance the value of our flats. The potential size of the upgrading program is approximately 370,000 units spread across 20 years, which works out to be 350 blocks per year. To ensure and maintain the high standards of the housing quality, Polymer concrete materials including polymer modified cement mortar, epoxy or PU floor screed and injection materials, and fibre-reinforced plastic (FRP) materials are extensively used in the new and upgrading projects. In this paper, the various applications of polymer concrete composites in Singapore are described and discussed. The various categories of polymer concrete composites are extensively used in Singapore’s public and private projects. To ensure and maintain the high standards of the building quality, independent testing and inspection plays a very important role. Through implementing a quality control program to ensure high standards in product quality and performance requirements, Housing & Development Board (HDB), Singapore's public housing authority and statutory board under the Ministry of National Development, screens and provides a comprehensive selection of quality products needed for HDB construction projects through HDB's Materials List [2] with a set of product evaluation requirement. The development of the requirements and specifications for various polymer concrete composite products are also described and discussed

Archaeological excavations at Gamzigrad - Romuliana in 2007-2008

Archaeological excavations at Gamzigrad - Romuliana in 2007-2008

An Experimental Study on the Thermal Performance of Cement Mortar with Granulated PCM

In this study the thermal performance of G-PCM replaced for find aggregate in mortar specimens was evaluated using TG-DTA. As a result, it was found that when solid changed into liquid, it absorbed heat, and when liquid changed into solid, it radiated heat. In addition, the fluidity and the compressive strength of mortar with G-PCM can be applied to the floor mortar and a wall finish material. Also the higher the replacement ratio, the larger the latent heat capacity. It was found that the mortar with G-PCM slowed the increase and decrease of temperature. Thus, the duration of pleasant indoor temperature is extended by the floor and wall mortar with G-PCM. In conclusion, G-PCM is expected to reduce the heating energy consumption.

Aquisgrani terrae motus factus est (part 2): Evidence for medieval earthquake damage in the Aachen Cathedral (Germany)

During archaeological and geotechnical investigations, the Carolingian part of the Aachen Cathedral (Germany) was excavated. The Aachen Cathedral was the first building in Germany to join the UNESCO World Heritage list. In the rock walls of the fundament and medieval floors, open cracks were found. Subsidence of the mortar floor of about 50 cm with lateral dragging, which was reconstructed during the construction of the Cathedral, can be observed. The main building is founded on Devonian limestones and shales, Pleistocene loess and Roman urban debris. The loess and loamy sediments show angular cracks and fragments, which are not related to permafrost features but are interpreted as shear and extensional fractures. Some of the cracks are filled with black clay from below as they open downwards. These structures are interpreted as injection features caused by thixotropy of clays. Open cracks, lateral spread and injections structures occur usually during earthquakes with a magnitude higher than 5.5. The historical German earthquake catalogues provide three important passages for historical earthquakes in the region of Aachen. Both fall into a relatively short time interval. One occurred in winter 803 AD, another one in 823 AD, and the last one in 829 AD between Ash Wednesday and Easter. Both notes tell of earthquake shaking and significant structural damage and fatalities. This and the constructional history allowed dating of the event, favouring the 803 AD event as the causative damaging earthquake observed in the Aachen Cathedral.

Restoration of Outdoor Plaster Pavement Floors in a Medieval Czech Castle

Substantial tests and analyses of an ancient exterior plaster floor at Karlštejn Castle in Bohemia have led to the design of a new material for replacing and repairing a historic mortar floor. The replacement material has a reasonably high degree of similarity and compatibility with an acceptable level of safety and reliability. The floor was cast in situ during extensive restoration works at the end of the nineteenth century and exhibits surprisingly high durability and strength. The investigation used some non-standard testing methods developed for small-size specimens. In designing the new material, attention was paid to lime mortars with hydraulic admixtures. A metakaoline-modified mortar was finally recommended as the repair and replacement material for restoring the rampart outdoor pavement of Karlštejn Castle.