SITI NUR ALIZA

Currently, Living Wall Systems (LWSs) are assuming great importance in the built environment, due to environmental and aesthetic advantages, as well as the use of urban residual space and Galvanized Steel underutilized surfaces of buildings. However, the maintenance and Galvanized Steel the durability of the materials used have been a challenge for architects and professionals in the field. The aim of this paper is to evaluate the anti-corrosion performance of a steel framing profile, galvanized carbon steel (55% Al-Zn), a sustainable material with easy assembly, to apply LWS in the hot and humid tropical climate of Niterói (Rio de Janeiro, Brazil). In order to create the conditions of the tests, “X” cut were made in Al-Zn coating, sanding, and application of epoxy and glass fiber-reinforced polyester. After the experiments that lasted four months, the 55% Al-Zn coating was analyzed using Scanning Electron Microscope (SEM) and energy dispersive X-ray spectroscopy (EDS). The results of the tests were promising for the use of this galvanized steel for application as a support for green vertical facades. 55% Al-Zn coatings are recommended for marine atmospheres due to their good anti-corrosion performance.

According to Mascaró & Mascaró [1] , the shapes that make up the natural landscape should be better exploited in order to create continuity between nature and the built space, producing a gradual transition from purely built, i.e. artificial, to the natural environment through organic nuances.

The proposal of the use of residual urban space and of underutilized areas of buildings for alternative elements harmonized with nature, looking to encourage the gardens for green roofs and façades, can improve, significantly, the pollution in cities. However, to become quantitative, a replacement of 10% – 20% of conventional roofs would be required [2] [3] .

In tropical, hot and humid climates, one of the important roles of vegetation is shade, whose purpose is to reduce the heat during the year, in addition to decreasing the surface temperatures of the floors and facades of buildings, as well as reducing heat felt by the residents of the urban environment [1] .

As an example of an efficient job in urban green areas, the building of the California Academy of Sciences in the San Francisco Golden Gate Park can be cited, which has a green roof of 10,000 m², designed by architect Renzo Piano. This allows a pleasant surrounding transition tree landscape and connects the building to the park, absorbing a great part of the incident rainwater per year, equivalent to 14 million liters [4] .

Fedrizzi et al. [5] state that the market of furniture for gardens is growing continuously, considering the well-being of industrialized countries, and different materials can be used to produce such furniture. Wood and plastic materials are often used, but they have some disadvantages to be considered, such as: discoloration and degradation by Ultraviolet Radiation (UV), as well as low mechanical resistance in the case of plastic artifacts, while high production costs and high maintenance are associated with wooden artifacts. Metal substrates such as aluminum or coated steel are preferred, especially considering that the mechanical resistance is good. Still, according to Fedrizzi et al. [5] , garden furniture is usually exposed to aggressive environments, resulting in damage on the surface that should be avoided, especially for aesthetic reasons.

The purpose of this paper is to evaluate the anti-corrosion performance of carbon steel galvanized support used in the manufacture of green facades.

Nowadays, the energetic efficiency becomes one of the major interests of the global Thermal Characterization  society. Thus, the energetic challenges of the new century enforce the scientific and industrial environment to the development of Thermal Characterization  new efficient materials, which present more than the classical thermal properties, according to the energy storage, energy consumption and other specific needs. In this context, the present work constitutes the third step of the development of a new kind of composite materials (micro-composites and nano-composites), using natural marl (clay) clay and biodegradable polymer, which is the PolyEthylene Glycol 6000 (PEG 6000). This step corresponds to characterization of the variation of the specific heat (denoted Cp) of the materials elaborated. So, in order to estimate the capacity of thermal energy adsorption, we utilized a SHIMATZU-DSC 60 Differential Scanning Calorimeter. The main results present the evolution of the Cp according to the PEG 6000 doping and also the specific melting enthalpy of the polymer within the natural clay matrix; by the way this enthalpy constitutes the specific heat stocked in the materials.

Recently, the Phase Change Materials (PCM) begin to constitute an important issue for the development of a new generation of construction materials. Several works essay to characterize the PCMs itself as the paraffin wax [1] – [3] , the mixture of several materials [4] , macro-incorporated into bricks or other construction materials [2] [5] [6] or micro-encapsulated within metallic shapes in order to stabilize the PCMs [7] .

The role of the encapsulation of the PCMs into construction materials permits an intelligent storage of energy within the bricks and the walls. The energy source could be natural as solar radiation or artificial as industrial furnace, etc. The energy is so stocked as a latent heat according to the melting temperature and the specific heat (capacity) of the PCMs materials.

In this work, we have incorporated the polyethylene glycol 6000 (PEG 6000) into a natural marl (clay) matrix, according to simple grinding and humid mixing techniques. We didn’t use any other artificial encapsulation. The aim is to exploit the energy storage of the polymer related to the endothermic transformations that occur in the neighborhood of the melting temperature, at approximately 60˚C.

Hence, at first, it is important to present the characteristics of the marl (clay) matrix used and the different microscopic or mesoscopic transformations that occur in the base material, according to the different elaboration parameters.

So, in order to define the clay material, it is essential to consider specific context or domain of work. For example, geologists define it as a dispersed granulated domain where the elementary particle has to be smaller than 2 µm [8] [9] . Weaver regroups all phyllosilicate minerals under a lager class, designated by “physils” without considering any size criteria [10] .

However, civil and geotechnical engineers are interested more by the macroscopic behavior expressed by the mechanical characteristics; such as the plasticity [11] , the elasticity and Young Modulus [12] , clay adsorption [13] [14] , etc.

The ceramists also have other interests; they classify these materials according to their allotropic transformations [15] [16] during the heat treatment, in order to optimize the ceramics production in industry.

A new tendency of the exploitation of this kind of materials, heat treated or not, wins more and more interests of construction industries, to replace classical building materials such as cement and concrete by the newest ones.

This interest is now boosted by the use of natural clay material which is abundant and considered as low-cost building material. But in another perspective, these materials could be concurrent to the classical construction materials [17] . The possibility of the consolidation of the clay with other ecological materials could affect greatly the mechanical and thermal properties of this latter.

Now, if some industries are interested in the production of construction bricks [17] , we are here interested in the fabrication of the same bricks. Indeed, we want to develop a new kind of coating which could be applied on the building surface in order to act on the thermal inertia and the thermal capacity of the walls.

Thus, the aim of this work is to characterize the new micro- & nano-composite composed by clay matrix and PEG 6000 reinforcement. This characterization is made by XRD analysis, DSC technique for thermal characterization, and some microscopy according to the SEM and the TEM techniques.

Some empiric models will be calculated in order to estimate the behavior of the characterized properties according to the PEG 6000 percentages.

For structural design and assessment of reinforced concrete members, the nonlinear analysis has become an Multistory Buildings important tool. The purpose of the pushover Multistory Buildings analysis is to assess the structural performance by estimating the strength and deformation capacities using static, nonlinear analysis and comparing these capacities with the demands at the corresponding performance levels. This paper aims to compare the results given by IBC2009 code and ESEE regulations. In this paper, four RC frames having 5, 15, 20 and 30 storeys were designed for seismicity according to both the recently adopted seismic code in Abu Dhabi (IBC2009) and the ESEE regulations. A pushover analysis is carried out for these buildings using SAP2000 (Ver. 15) and the ultimate capacities of the buildings are established. The obtained pushover curves and plastic hinges distributions are used to compare between the IBC2009 code and ESEE regulations. The comparison showed that there was variation in the obtained results by the two codes and the buildings designed by IBC2009 code were more vulnerable.

Recently, the nonlinear static analysis (NSA) method has emerged as an attractive method for evaluating the performance of new and existing buildings. This is primarily because of the ability of the NSA method to provide estimates of the expected inelastic deformation demands and to help identify design flaws that would be otherwise obscured in a linear analysis of the building. In addition, the features of the NSA method are available to the structural engineer without the modeling and computational effort of a nonlinear time-history analysis. Therefore, extensive research efforts have been devoted to investigatingthe structural behavior under seismic loads by using pushover analysis.

Sung et al. (2013) [1] investigated the shear failure behavior of beam-column joints (BCJs) of RC frame structures by the means of nonlinear static pushover analysis (NSPA). The authors proposed a new NSPA procedure to assess effectively the shear failure of BCJs and its seismic capacity and the progressive failure of the joints. Furthermore, they provided novel plastic hinges (PHS) characteristics of BCJs and an innovative cross-strut model to simulate detailed joint behavior in NSPA. The analytically derived pushover curves were compared to three different full-scaled RC frames to validate the proposed methodology.

Hassaballa et al. (2014) [2] performed a 3D NSPA to study the performance of existing four-storey RC flat slab building in both positive and negative X and Y directions separately. The evaluation was carried out by using SAP2000 software (Ver. 14) [3] . It was observed from the analysis that the building was not safe and needed retrofitting in the X-direction because there were some elements exceeded the limit level between life safety (LS) and collapse prevention (CP), whereas, all structural elements did not reach the limit in Y-direction.

Maske et al. (2014) [4] performed 3D NSPA on 5 and 15 storeys frame structures using SAP2000 software (Ver. 14). A detailed description of pushover method and capacity curve properties was presented. In addition, the authors evaluated different parameters that affected seismic assessment of frame structures, e.g. pushover and capacity curves. It was concluded that the considered case studies performed reasonably under seismic loads.

Choudhary and Wadia (2014) [5] investigated the effect of shear walls on the seismic performance of the RC frame structures. Two case studies were considered in the analysis, in which one was symmetrical building and the other was unsymmetrical building (i.e. L-shaped building). It was found that providing shear walls led to a significant decrease in both buildings. Moreover, placing the shear walls in the short direction is mandatory for the unsymmetrical building since they provide more reduction in roof displacement.

Aleksieva (2015) [6] conducted a comparative study between the NSPA and incremental dynamic analysis (IDA) to investigate the structural behavior of a RC three- storey frame building under the seismic loading. The aim of the paper was to highlight the advantages of each method and their applicability in structural seismic design. The OpenSees software [7] was used to conduct the analysis of the building. It was concluded that the pushover analysis produced accurate results in the elastic region, whereas the results were very conservative in the nonlinear region.

Kadlag and Kenkar (2016) [8] performed a parametric study to investigate the impact of the variation of bay width and base condition on the structural behavior of RC frames by the means of pushover analysis. To investigate the soil-structure interaction (SSI) effects, three base conditions were considered which were fixed base, medium soil and soft soil. Moreover, the RC framed buildings’ height was G + 10, G + 15 and G + 20 and the width varied from 4 to 5 meters. It was observed that with the increase of bay width and building height, the number of failed PHs was increasing as well for all the base conditions.

Keerthan and Babu (2016) [9] carried out a pushover analysis on 3D 10 storeys RC frames in order to investigate the effect of mass irregularities on the structural behavior under severe earthquakes. ETABS software (Ver. 9.7) was used to carry out the pushover analysis. The main findings of study were that the increase in lateral displacement of mass irregular frame was promotional to the heavy mass floor level. Furthermore, the mass irregular RC frames experienced significant interstorey drifts compared to the regular RC frames.

The focus of this paper is on the evaluation of the nonlinear performance of regular multi-storey reinforced concrete buildings using the NSA and pushover analysis under the loads of the IBC2009 [10] and the Regulations of the Egyptian Society for Earthquake Engineering (ESEE) [11] . Moreover, the obtained pushover curves and plastic hinges distributions are used to compare between the IBC2009 code and ESEE regulations. The outcome of this study is to check the vulnerability of both codes, and to provide useful information for further seismic designs in UAE.

The objective of this study is the characterization of mould inside and in the surface wall of a Hospital Environment . The present research was made on the wall of the Clinical Hospital of the Hospital Environment Federal University of Paraná, Brazil. For the methodology the samples were extracted from the surface, mortar and brick. The samples were spread on Petri plates containing Sabouraud dextrose agar and incubated at 25℃ for seven days. The results of the 90 samples collected showed growth of 39% of colonies with the following distribution of microorganisms: Aspergillus (present in 27% of samples), Cladosporium, Absidia, Rhizopus, Rhodotorula, Fusarium, Penicillium and Aspergillus flavus. Within the investigated substrate, three species of different fungi were identified: Aspergillus flavus, Aspergillus fumigatus and Aspergillus niger.

The study of mold growth in the walls interior of masonry, particularly fungi present in grout coatings, is necessary whereas in a wall demolition process, possible fungal spores, that may be latent inside, can contaminate the environment. If the demolition is conducive to the contamination of air, these spores can be inhaled by immunocompromised patients who do not offer resistance to reproduction, which in turn provide favorable conditions of temperature, humidity and substrates for growth as analysis of Zanon and Alves [1] .

The fungi of genre Aspergillus, cause of aspergillosis, have the rapid growth at temperature near 37˚C, which coincides with the range of variation of body temperature. The fungal spores can lodge, in some cases, in the brain region, or even in the lungs where they multiply cause infection that causes damage to the affected organ and enhances the appearance of other diseases such as tuberculosis and pneumonia, cited for [2] or the study of [3] .

Studies have reported a significant increase in patients who developed aspergillosis associated with periods when remodeling and construction of the hospital environment and its proximity are conformed [4] .

In regions such as Thailand, for example, fungus infection ranking third after frequent cause of diseases such as tuberculosis and cryptococcosis in HIV (Human Immunodeficiency Virus) confirmed the development as studies of Ranjana et al. [5] .

Filamentous fungi of the Aspergillus genre are opportunistic. These are the most cited in the literature and are the most common in transplant patients of bone marrow and neutropenic or studies of [6] .

In turn, research on fungal nutrition in building materials indicates that the salt content and the moisture present in the mortar can influence the growth of fungi [7] .

Fungi can absorb nutrients present in building materials. The main nutrients are those derived from petroleum hydrocarbons which may be adhered to the concrete, mortar and other materials [8] .

So in the interest of identifying the fungi that may be present in different environments, this study aims to characterize fungi in two different regions of a hospital environment.

This paper presents study of optimization of Fink Truss by Fully Stressed Design (FSD) method using STAAD.Pro software version STAAD.Pro V8i (SELECT series 5). Three spans of the Fully Stressed Design trusses have been considered and each truss has been subjected to 27 types of load cases by changing nodal load locations. Central node load has been kept constant in each truss as 100 kN. Three sets of load condition is taken, viz, 100 kN, 120 kN and 150 kN. Total 81 trusses have been analyzed in this study to achieve a target stress of 100 MPa. Steel take-off for each case and maximum displacement for each case have been calculated and compared in this study and it shows that weight does not always increase with increase in the span or height. Results of the study could be helpful in designing a truss that does not waste material.

A truss is a structural object comprising of a stable and systematic arrangement of slender interconnected members. Each member in a truss is straight and is connected at joints. Elements in a truss are arranged in such a pattern so that they produce an efficient, light weight, load-bearing members. Joints in truss carry zero moments since members are connected by frictionless pin. Hence, truss members carry only axial forces which are either in compressive or tensile in nature. Trusses have a high use in modern construction and are used commonly in buildings where support to roofs, floors and internal loadings is readily provided. Steel trusses are most widely used in industrial buildings. These days, most of the trusses are made of steel, however, in some cases timber and concrete trusses are also utilized. The sections used for steel trusses are generally angle sections, square hollow sections, pipe sections, T-sections, C-channel sections, etc. In any case of construction of structure, the main objective is to reduce the cost of the project and fulfill structural requirement. Hence, it becomes necessary to optimize the structure to fulfill the economical requirement. The optimum design of a structure should satisfy various constraint limits, and stress and local stability conditions. The optimum shape of a truss depends not only upon its topology, but it also depends on distribution of element cross-sectional areas. Some of the basic optimization techniques are: Mathematical programming, Optimality criteria, Approximation methods and Fully Stressed Design method. In past, many researchers had carried out research on optimization of truss.

Andrew B. Templemen (1976) introduced theories of dual approach in his paper which showed the implication and usefulness of dual approach [1] . This study considered problem of determining optimal member sizes which minimized weight of a pin jointed truss of fixed geometry which satisfied certain constraints. William Prager (1976) discussed the optimal design of truss which had bars and connected to loaded joints on a horizontal ceiling where single and two alternative loads were considered [2] . Samuel L. Lipson and Krishna M. Agrawal (1974) proposed a complex method of optimization in which geometric and topological variable were included. Method is useful in solving discrete member spectrum which included behavior of members [3] . H. Randolph Thomas Jr. and Daniel M. Brown (1977) presented an algorithm which covered application of optimization method for roof truss system considering the cost function as parameter [4] . Andrew B. Templemen (1983) explained the reason why only some research output could be applied to designing [5] . Rajasekaran (1983) has carried out research on optimal design of industrial roof system by using computer aided technique. He investigated on finding optimal spacing of roof truss of a given span and length to get optimum weight [6] . Ohsaki (1995) carried out a study on optimization of trusses considering displacement and stress constraints in different static loading condition by using the concept of genetic algorithm [7] . John E. Taylor and Mark P. Rossow (1977) presented calculation on optimal design of trusses by considering design variables as constraints and optimally criteria based on strain energy considerations. They have given a formulation to solve number of problem to give optimal member size and member layout by giving location of joints and loads [8] . Surya N. Patnaik and Dale A. Hopkins (1998) presented a paper on fully stressed design by use of analytical and graphical methods and by taking displacement constraints [9] . Lluis Gil and Antoni Andreu (2001) presented a method to give optimum shape and cross section of a plane truss by considering stress constraints and geometrical constraints. They used fully stress design method for the optimization of cross section and conjugate gradient method for optimization of coordinates [10] . Wang et al. (2002) presented a paper on optimization by taking node shift method for 3-dimensional truss in terms of nodal coordinates and elemental cross-section areas. Two typical trusses are examined to illustrate validity of the method [11] . Huan Li Teng Hai-Wen (2010) presented fully stressed design of statically indeterminate truss. His work and calculation can be used as reference for engineering practice [12] . Atai Ahrari and Ali A. Atai (2013) carried out a study on fully stressed design evolution strategy of truss [13] . Ganzreli (2013) presented a paper on fully stressed design method of optimization for determining trusses by taking displacements constraints [14] . Mustafa Sumayah et al. (2015) presented a paper on optimization of plane trusses by using STAAD.Pro software. Six types of trusses were analyzed by taking a group of design constraints that showed structural configuration [15] . Osman Shallan et al. (2014) carried out a study on genetic algorithm for optimum design of plane and space trusses by using nodal deflection as constraints [16] [17] .

In this study, Fully Stressed Design method has been utilized for optimization of Fink Trusses by using STAAD.Pro V8i (SELECT series 5) software. For this, 9 different load cases have been considered for three different spans. The central load for each Fink Truss has been kept constant throughout the analysis. So by the combination of load and spans, the total 81 cases have been analyzed and steel take-off and displacement are calculated. The section used in this study is pipe section.

Seluruh proses manufaktur di pabrik modern sekarang dikendalikan melalui sistem kontrol logika terprogram berbasis mikroprosesor untuk menjaga kualitas pembuatan semen yang seragam dan tingkat produksi yang tinggi. Seluruh operasi pabrik dalam pembuatan semen dikendalikan secara terpusat dalam satu ruang kendali dan pabrik mempekerjakan tenaga kerja minimum.

Tanaman modern juga telah melakukan perawatan yang memadai untuk mencegah pencemaran lingkungan dan gangguan debu di sekitarnya. Pabrik semen memiliki elektro-statik presipitator (ESP) yang dipasang untuk memeriksa emisi debu. Filter kantong dan rumah kantong kaca terletak di berbagai lokasi untuk mencegah emisi debu dan untuk memastikan suasana yang sehat dan bebas bahaya.

Berikut tiga operasi berbeda yang terlibat dalam pembuatan pengaturan normal atau semen biasa atau Portland:

 Pencampuran bahan baku

Bahan baku seperti batugamping atau kapur dan serpih atau tanah liat dapat tercampur baik dalam kondisi kering maupun basah. Proses tersebut dikenal sebagai proses kering atau proses pencampuran basah.

Proses kering (teknologi modern)

Dalam proses ini, bahan mentah pertama-tama dikurangi ukurannya sekitar 25mm di penghancur. Udara kering kemudian dialirkan melalui bahan-bahan kering ini. Bahan-bahan ini kemudian dihancurkan menjadi bubuk halus di pabrik bola dan pabrik tabung. Semua operasi ini dilakukan secara terpisah untuk setiap bahan mentah dan disimpan di hopper. Mereka kemudian dicampur dalam proporsi yang benar dan disiapkan untuk pengumpanan rotary kiln. Bubuk bahan mentah yang digiling halus ini dikenal sebagai campuran mentah dan disimpan di tangki penyimpanan.

Proses pengeringan telah dimodernisasi dan digunakan secara luas saat ini karena alasan berikut:

• Persaingan: Saat ini, beberapa pabrik semen proses kering saling bersaing satu sama lain. Konsumen semen pada umumnya dan para insinyur sipil yang berpraktik pada khususnya sangat diuntungkan oleh persaingan tersebut.
• Daya: Pencampuran bubuk kering kini telah sempurna dan proses basah, yang membutuhkan konsumsi daya yang jauh lebih tinggi, dapat diganti dengan percaya diri.
• Kualitas semen: Diketahui bahwa kualitas produksi tidak lagi bergantung pada operator dan pekerja yang terampil karena pengaturan dan proporsi suhu dapat dilakukan secara otomatis melalui ruang kontrol terpusat.
• Teknologi: Ada beberapa kemajuan dalam instrumentasi, komputerisasi dan kendali mutu.

Berikut prosedur pembuatan semen dengan proses kering menggunakan teknologi modern:

1. Bongkahan batu kapur hingga ukuran 1.2m diangkut dalam tempat sampah besar hingga kapasitas 300kN dan dibuang ke hopper mesin penghancur.
2. Penghancur hammer mill dari satu tahap sekarang digunakan untuk penghancuran. Batu kapur yang dihancurkan sekarang berukuran 75mm dipindahkan dari crusher dengan serangkaian konveyor untuk ditumpuk. Penumpuk membantu menyebarkan bahan yang dihancurkan dalam lapisan horizontal dan reklamasi membatasi variasi kalsium karbonat dalam batu kapur yang dihancurkan menjadi kurang dari 1% sehingga meminimalkan variasi kualitas bahan. Bahan berlempung atau tanah liat yang ditemukan di tambang juga dibuang ke mesin penghancur dan ditumpuk bersama dengan batu kapur.
3. Bahan yang hancur diperiksa kandungan kalsium karbonat, kapur, alumina, oksida besi dan silika. Setiap komponen yang ditemukan pendek ditambahkan secara terpisah.
4. Bahan aditif dan batu kapur yang dihancurkan dikirim ke hopper penyimpanan. Bahan mentah diumpankan ke pabrik mentah melalui konveyor dan proporsional dengan menggunakan pengumpan timbang yang disesuaikan dengan analisis kimiawi yang dilakukan pada bahan baku yang diambil dari hopper dari waktu ke waktu.
5. Bahan-bahan tersebut digiling hingga kehalusan yang diinginkan di pabrik mentah. Serbuk halus yang muncul sebagai hasil dari penggilingan di penggilingan mentah diledakkan ke atas, dikumpulkan dalam siklon dan diumpankan ke silo pencampuran dan penyimpanan kontinu berukuran raksasa dengan menggunakan aeropole.
6. Bahan dijatuhkan hanya dengan gravitasi dari pencampuran ke silo penyimpanan sehingga menghemat daya. Material tersebut kemudian dipompa kembali menggunakan aeropole ke dalam preheater dengan temperatur dinaikkan dari 60 ° C menjadi 850 ° C dengan cara meniupkan gas panas pada temperatur 1000 ° C.
7. Maerial dari dasar preheater diumpankan ke rotary kiln.

Pembakaran

Dalam teknologi modern proses kering, batubara yang dibawa dari ladang batubara dihancurkan di penggilingan batubara vertikal dan disimpan dalam silo. Itu dipompa dengan jumlah udara yang dibutuhkan melalui pembakar. Bahan mentah yang telah dipanaskan sebelumnya menggelinding ke bawah tanur dan dipanaskan sedemikian rupa sehingga karbon dioksida dikeluarkan dengan gas pembakaran. Bahan tersebut kemudian dipanaskan hingga suhu hampir 1400 ° C hingga 1500 ° C saat menyatu. Produk fusi dikenal sebagai klinker atau semen mentah. Ukuran klinker bervariasi dari 3mm hingga 20mm dan sangat panas saat keluar dari zona pembakaran kiln. Suhu klinker di outlet kiln hampir 1000 ° C. Sebuah tungku putar berukuran kecil disediakan untuk mendinginkan klinker yang panas. Itu diletakkan dalam arah berlawanan dan klinker yang didinginkan yang memiliki suhu sekitar 95 ° C dikumpulkan dalam wadah dengan ukuran yang sesuai.

Penggilingan

Klinker yang diperoleh dari rotary kiln digiling halus di ball mill dan tube mill. Selama penggilingan, sedikit gipsum ditambahkan, sekitar 3 sampai 4 persen. Gypsum mengontrol waktu pengaturan awal semen. Jika gypsum tidak ditambahkan, semen akan mengeras segera setelah air ditambahkan. Gipsum bertindak sebagai penghambat dan menunda tindakan pengaturan semen. Dengan demikian memungkinkan semen untuk dicampur dengan agregat dan ditempatkan pada posisinya. Penggilingan klinker di pabrik modern dilakukan di pabrik semen yang berisi bola baja kromium dengan berbagai ukuran. Bola-bola ini menggelinding di dalam gilingan dan menggiling campuran yang dikumpulkan dalam hopper dan dibawa ke lift ember untuk disimpan di silo. Semen dari silo diumpankan ke mesin pengemas. Sebagian besar pabrik modern memiliki pabrik pengemasan listrik yang memiliki ketentuan untuk menghitung berat kantong kosong dari berbagai jenis dan untuk memastikan berat bersih kantong semen 50kg dalam batas ± 200g. Setiap kantong semen berisi 50kg atau 500N atau sekitar 0,035m3 semen. Kantong ini secara otomatis dibuang dari pengemas ke sabuk konveyor ke area pemuatan yang berbeda. Mereka disimpan dengan hati-hati di tempat yang kering.

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