Buildings In Earthquake-prone Areas Research Articles

ANALYSIS OF THE EFFECT OF COLUMN DIMENSION VARIATIONS ON THE STRUCTURE OF A 12-STORY APARTMENT BUILDING

High-rise buildings are building structures that are vulnerable to lateral forces so they must be designed to be able to withstand lateral loads, such as wind and earthquakes. Buildings in earthquake-prone areas must be planned to be able to withstand earthquakes. Basically, buildings that are designed to withstand earthquakes, the columns must be strong. The purpose of this study is to determine the effect of column dimension variations on building structure and obtain effective and efficient column dimensions in the planned building. The research method is preceded by conducting a literature study. Furthermore, data collection was carried out, making preliminary design of the structure, and conducting structural analysis using the help of ETABS 19.1.0 software. The results of analysis and comparison show that the smallest displacement value occurs in model 1 of 81.724 mm in the X direction and 83.776 mm in the Y direction. While the largest displacement occurs in model 3 of 95.222 mm in the X direction and 96.678 mm in the Y direction, but the displacement that occurs in model 3 is still within the permissible safe limit (100mm).

A Review on Seismic Analysis of RCC and Steel Structures using Linear and Non-linear Static Analysis

Abstract: An earthquake can cause significant harm to various aspects, including buildings, general life, and particularly multistory structures. In India, structures constructed in earthquake-prone regions, as defined by IS 1893: 2002, must be designed to withstand the loads, stresses, and consequences of earthquakes. Several techniques are available for assessing multi-story structures in this context, such as the Response Spectrum Method, Equivalent Lateral Force Method, Time History Method, and adhering to specific code provisions. Numerous researchers have undertaken studies to analyze multi-story buildings using one or more of these methods. However, there exists still a confusion about an effective and efficient method preferred for seismic design of multi-story buildings. Among the various approaches, the seismic coefficient method and response spectrum method are the most widely used. This comparative investigation aims to review research reports that have employed the Equivalent Lateral Force Method and Response Spectrum Method to analyze multi-story buildings in earthquake-prone areas. The design response spectrum serves as the initial reference point for most established seismic design and assessment procedures. It primarily dictates the inertia forces that buildings and structures must withstand during an earthquake. This paper aims to introduce and discuss contemporary concepts regarding the creation and utilization of earthquake design response spectra. Additionally, the paper highlights the various methods of seismic analysis being investigated in the past literature. It also gives an overview of various investigations being carried out using linear and non-linear static analysis of RCC structures. Many of the ideas presented are specifically aimed at aiding engineers who work in regions with low to moderate seismic activity. The main objective is to inform engineers about modern approaches to developing response spectra. This knowledge can then be applied effectively in both analytical and design contexts when dealing with earthquake-related challenges

Seismic Behavior of Structure with Cantilever Projections in Different Zones

Abstract: In this research paper, the main focus is on understanding how structures with constant cantilever projections of 1m perform when subjected to seismic forces. To carry out the analysis, the researchers utilize ETABS software, which is commonly used in the field of structural engineering. The study investigates two types of buildings: a 5-storey building and a 10-storey building. By using the static method, the researchers evaluate various aspects of the structure’s seismic behavior. This includes examining the story displacement, which refers to how much each floor moves during an earthquake. They also examine the overturning moment, which helps to assess the potential for the structure to rotate or tip over due to seismic forces. Additionally, the researchers analyze the base shear, which represents the total force experienced by the building's foundation due to seismic activity. By conducting these analyses, the researchers aim to gain insights into how the structures with 1m cantilever projections perform in different zones under seismic conditions. This information can be valuable for designing safer and more resilient buildings in earthquake-prone areas.

Review of Methods for Seismic Strengthening of Masonry Piers and Walls

The seismic strengthening of buildings in earthquake-prone areas has been a hot topic in recent years, especially for masonry structures. Because there are so many masonry structures and because most were built before seismic codes existed, their seismic vulnerability is an unavoidable issue. Over the years, several methods for seismic strengthening of masonry piers and walls have been developed that may roughly be classified as traditional or modern. In this paper, an overview of the most commonly used and effective methods will be presented with an emphasis on modern methods based on a Fabric-Reinforced Cementitious Matrix. The advantages and disadvantages will be discussed from the point of view of usability, feasibility, and effectiveness. Finally, a comparison will be drawn between traditional and new methods based on composite materials.

Seismic isolation effect of rubber-sand mixture cushion under different site classes based on a simplified analysis model

The use of rubber-sand mixture (RSM) cushion in geotechnical seismic isolation (GSI) systems is an emerging technique for protecting buildings in earthquake-prone areas. The advantage is that RSM with high shear resistance and low shear modulus improves the foundation soil, allowing seismic energy to be partially dissipated in the cushion before it is transmitted to the structure. However, the isolation effect of the RSM cushion considering site classification has not been recognized due to the complexity of the problem. In this paper, a simplified analysis model is established to study the seismic performance of the RSM cushion, in which 195 ground motion records are obtained from different site conditions according to the Code for Seismic Design of Buildings GB50011-2010, reflecting the influence of site classification. By using the developed theoretical analysis method, the seismic isolation effect of the RSM cushion under different site classes is investigated. The key influencing factors to be considered include the cushion thickness, base pressure and seismic excitation intensity. The results show that: 1) The isolation effect of the underlying RSM cushion on the superstructure is affected by site classification. The harder the site, or more specifically, the shorter the predominant period of the site, the better the isolation effect of the RSM cushion. 2) For the same site classification, the isolation effect increases with increasing cushion thickness, base pressure and seismic excitation intensity. In particular, the robustness of the seismic performance of the RSM cushion deteriorates upon reaching a cushion thickness of 500 mm, and this deterioration in robustness is independent of site classification. Overall, the present study is the first systematic analysis of the effects of ground motion on GSI systems with RSM as the core under different site classes, and the research findings are of great significance for the low-cost seismic design of residential houses in developing countries.

Thermo-mechanical characterization and hysteretic behavior identification of innovative plastic joint for masonry infills in reinforced concrete buildings

Modern approaches in buildings design strive to fulfill multiple performance requirements simultaneously. Accordingly, as far as buildings in earthquake-prone areas are concerned, damage limitation under seismic loads must be ensured while paying attention on the issues related to the environmental sustainability of the construction, ranging from its ecological footprint to the thermal efficiency. Masonry infills in framed reinforced concrete buildings are especially important in this context. In fact, they are vulnerable to earthquakes and greatly impact on the environmental sustainability of the building because they employ a significant amount of construction materials and influence its energy consumption throughout the lifetime. In light of this, the main novelty of the present work is concerned with a new deformable joint for masonry infills in framed reinforced concrete buildings. A detailed description of such innovative system for masonry infills is provided, together with numerical and experimental investigations about its mechanical and thermal behavior. The proposed joint is made of recycled plastic material, namely Regenerated Polypropylene Homopolymer. Geometry and manufacturing process of the proposed joint are initially described. Then, stress–strain relationships for the plastic material are obtained from uniaxial tensile tests at different temperatures. An assembly of fired hollow clay bricks and plastic joints is also tested under in-plane cyclic load, and a phenomenological model is thus proposed to simulate the experimental hysteretic behavior. Finally, experimental tests and finite element-based numerical simulations are performed to investigate the thermal performance of masonry infills with plastic joints.

Analysis of Steel Plate Shear Wall System Using Finite Element Analysis

Abstract: A seismic wall is a lateral load resistance system used in high-rise buildings in earthquake-prone areas. The aim of the current research is to investigate the shear behavior of his SPSW using finite element method techniques. SPSW modeling and structural analysis are performed in software ANSYS 18. Critical areas of high stress and deformation are determined from the FEM analysis. The mode shapes and natural frequencies of SPSW are determined. Both structural and modal analyses, the highest deflection was observed at the top plate of the SPSW, indicating that this is the most fragile region under static and dynamic loading conditions

Perancangan Struktur Rangka Pemikul Momen Khusus (SRPMK) Ruko 4 Lantai Berdasarkan SNI 2847-2019 dan SNI 1726-2019

Palu City is located in an earthquake-prone area. To Construct a building in earthquake-prone areas, many people like to construct buildings far away from the epicenter, we should be able to construct buildings in earthquake-prone areas without any worries about the resilience of the building related to seismic load. In this final project, a 4 (four) storey shophouse will be designed as the Special Moment Resisting Frame method using the SNI-2847-2019 and SNI- 1726-2019 standard. The seismic load was simulated using the response spectrum and the structural element was analyzed by 3D Structural Analysis Programme. The design results meet the dimensions of each structural elements. There were slab thickness 125 mm, column dimensions 600 mm x 600 mm, dimensions of beam 400 mm x 600 mm, the dimensions of the joist 200 mm x 400 mm and tie beam dimension 400 mm x 600 mm with the reinforcement obtained from each structural element meet the requirements of SNI-2487- 2019, Standard of structural concrete for buildings.

Seismic reliability of steel SMFs with deep columns based on PBSD philosophy

Steel special moment frames (SMFs) represent a common structural solution for buildings in earthquake-prone areas. However, when SMFs are selected by structural engineers, one of their main concerns is to satisfy the permissible drifts recommended by codes. As a common option, the use of deep columns may be a feasible alternative to reduce lateral deformation of SMFs. In this paper, the authors explore the performance of steel SMFs with deep columns by evaluating their seismic reliability. Since earthquake-resistant design is moving from the prescriptive-code to performance-based seismic design (PBSD), an alternative safety approach is integrated with the PBSD philosophy. In this way, SMFs are represented by finite elements and excited by seismic loading incorporating all major sources of nonlinearity as material behavior, geometric deformations, and connections of structural members. The novel approach is developed using the first-order reliability method, response surface method, and an advanced probabilistic scheme. The computational benefits and accuracy of the proposed method are validated using traditional Monte Carlo simulation. The implementation potential is showcased with the numerical evaluation of three 9-story steel SMFs: the first one using columns of medium size and the other two considering deep columns. The seismic reliability is extracted for every model considering serviceability performance functions correlated with performance levels of collapse prevention, life safety, and immediate occupancy. In addition, the contribution of the post-Northridge connection in the steel SMFs is incorporated. Finally, without being too much critical, the use of deep columns in the models of this paper seems to be a step in the right direction to reduce weight, decrease cost, and increase structural reliability. However, it must be stated that deep columns considered in the models have no instability concern because of their low slenderness ratios.

Seismic Assessment of Tall Buildings Designed According to the Turkish Building Earthquake Code

For the first time, the 2018 edition of the Turkish Building Earthquake Code has added a dedicated chapter for the design of high-rise buildings in earthquake-prone areas. Keeping in view the widely practised design option of rigid shear walls at the centre of a high-rise structure, the latest code has additionally defined limits for shear-wall axial forces in high-rise buildings. The new shear-wall axial force limits have not been independently investigated for optimal design and criticality. This calls for a detailed investigation of the newly defined axial force limits for the design of high-rise buildings in Turkey, where seismic activity has historically remained high. This study, therefore, investigates the effect of variation in limit values of shear wall axial forces on the collapse prevention of such buildings. A high-rise building designed entirely according to the code was chosen as the base model. The location of the building is in Istanbul, which has the highest number of tall buildings as compared to other cities in Turkey. A total of 7 alternative models were created by changing the concrete material class and the thickness of shear walls. This approach allowed us to quantify the effect of shear-wall thickness and its criticality against another important design consideration, i.e., the compressive strength of concrete. Forty different earthquake ground motion records were used to analyse the models to determine how critical the axial force ratio of the shear walls is in terms of collapse probability. The method proposed in the Federal Emergency Management Agency (FEMA) document FEMA P695 was followed to determine the collapse levels for the high-rise structures. A nonlinear analysis was performed to analyse the failure safety of the models. Results indicate that an increase or decrease in the axial force ratios by more than 15% renders the structure either overdesigned or deficient. Doi: 10.28991/CEJ-2022-08-03-011 Full Text: PDF

EVALUASI KINERJA STRUKTUR BANGUNAN DENGAN METODE PUSHOVER ANALYSIS PADA GEDUNG RUMAH SAKIT STROKE NASIONAL BUKITTINGGI

Earthquake phenomena are natural phenomena that greatly affect buildings, especially high-rise buildings. Planning of earthquake-resistant building structures is very important in Indonesia, considering that most of the area is located in earthquake areas with moderate to high intensity. Buildings in earthquake-prone areas must be designed to be able to withstand earthquakes. The latest planning trend is performance based seismic design, which utilizes computer-based non- linear analysis techniques to analyze the inelastic behavior of structures from various ground motion intensities (earthquakes), so that their performance can be known in critical conditions. Further action can be taken if it does not meet the required requirements. The purpose of this study was to determine the pushover analysis procedure to evaluate the performance of the building structure and to determine the pattern of the collapse of the building structure after being analyzed by pushover. This study uses the Static Pushover Analysis method with reference to the displacement coefficient method (FEMA 356, 2000). The lateral load used is the result of an equivalent static analysis which is carried out monotonically in one direction. Research shows that there are several conclusions. First, the displacement of the maximum pushover result (δmax) in the XZ direction, which is in step-7, is greater than the displacement target (δt), with a figure of 61541.4681 mm > 58.212 mm. Second, the displacement of the maximum pushover result (δmax) in the YZ direction, namely in step-5, is greater than the displacement target (δt), with a figure of 10450.54 mm > 58.212 mm. Third, the evaluation in the XZ direction is still safe even though max > t, because all beam elements in the portal appear plastic hinges with levels A-B which are still elastic, all marked in pink. The distribution of plastic hinges that occur at all steps shows that no structural member exceeds the performance limit so that it can be said that the performance of the structural component is in a safe condition. Fourth, the structural members in the YZ direction are also safe because max > t and the plastic hinge distribution scheme shows the structural members marked in pink with levels A-B. Keywords: pushover, non-linear, plastic hinge

Study of Building Safety Monitoring by Using Cost-Effective MEMS Accelerometers for Rapid After-Earthquake Assessment with Missing Data.

Suffering from structural deterioration and natural disasters, the resilience of civil structures in the face of extreme loadings inevitably drops, which may lead to catastrophic structural failure and presents great threats to public safety. Earthquake-induced extreme loading is one of the major reasons behind the structural failure of buildings. However, many buildings in earthquake-prone areas of China lack safety monitoring, and prevalent structural health monitoring systems are generally very expensive and complicated for extensive applications. To facilitate cost-effective building-safety monitoring, this study investigates a method using cost-effective MEMS accelerometers for buildings’ rapid after-earthquake assessment. First, a parameter analysis of a cost-effective MEMS sensor is conducted to confirm its suitability for building-safety monitoring. Second, different from the existing investigations that tend to use a simplified building model or small-scaled frame structure excited by strong motions in laboratories, this study selects an in-service public building located in a typical earthquake-prone area after an analysis of earthquake risk in China. The building is instrumented with the selected cost-effective MEMS accelerometers, characterized by a low noise level and the capability to capture low-frequency small-amplitude dynamic responses. Furthermore, a rapid after-earthquake assessment scheme is proposed, which systematically includes fast missing data reconstruction, displacement response estimation based on an acceleration response integral, and safety assessment based on the maximum displacement and maximum inter-story drift ratio. Finally, the proposed method is successfully applied to a building-safety assessment by using earthquake-induced building responses suffering from missing data. This study is conducive to the extensive engineering application of MEMS-based cost-effective building monitoring and rapid after-earthquake assessment.

Concrete Tensile Strength Test Using Different Sand Gradation Zones t o Mitigate Earthquake Buildings

Sand is one of the building materials forming the concrete mass. Sand has a type based on quarry sources, namely sea sand, river sand and mountain sand. Sand has different characteristics such as gradations (grain fineness), unit weight, mud content. Based on the SK-SNI 03-2834-1993 standard, sand has a grain size which is classified as very rough, rough, medium, smooth and very smooth. Sand that has a good gradation is separated in the form of a graph as zones 1 to 4. Concrete has good compressive strength but is weak on tensile strength. To increase the tensile strength, fiber can be added. The use of wire fiber is expected to increase the performance of buildings in earthquake-prone areas. In this study the fiber used was metal wire with a length of approximately 2 cm, designed compressive strength of concrete of 25 MPa, with a cylindrical sample diameter of 15cm and a height of 30cm, 3 month old age split tensile strength test was conducted, by using sea and mountain river sand with different zones. The results obtained that the division of the sand zone into rough to fine classification does not provide a significant trend for the tensile strength of the concrete. Mechanically, the addition of wire fibers for Air Lakok sand, Lubuk Kebur river sand and Penanding river sand has decreased the tensile strength. While the sea sand of Selubuk, the river sand of Talang Rasau and the mountain sand has increased tensile strength. Visually, all concrete that is given wire fiber has better ductility, where the concrete does not experience brittle cracks and the elements are still bound to each other.

Cyclic numerical analyses on wood-based in-plane retrofit solutions for existing timber floors

Timber-based strengthening interventions on existing wooden floors showed great potential to improve the diaphragm response in seismic rehabilitation. This is particularly important in masonry buildings in earthquake prone areas, to achieve a global box behaviour. A numerical model able to describe the non-linear cyclic behaviour of unreinforced and reinforced floors is illustrated in the present paper. Since in strengthening interventions on timber floors made by the application of timber-based panels, the fasteners proved to be the main source of non-linearity, a proper connector element is developed as an assembly of non-linear springs. Each one describes a particular aspect of the fastener behaviour in order to consider stiffness and strength degradation during the cyclic response. The model was validated by means of experimental data, acquired in a previous test campaign or available in literature. It can be used to analyse and optimize other in-plane strengthening configurations of timber floors, changing parameters as geometry, fastener spacing, sheathing orientation, opening location. This detailed numerical model can be useful also to calibrate the simpler macro models generally used for the floors in the non-linear evaluation of seismic global behaviour of buildings. A few parametric analyses and an example of a life-size floor are also presented as case studies.

Dynamic Characteristics and Time-History Analysis of Hydraulic Climbing Formwork for Seismic Motions

With the widespread use and increasing cycle life of climbing formwork to construct high-rise buildings in earthquake-prone areas, the risk of earthquakes during the construction period increases. Hence, it is necessary to analyze the seismic response of climbing formwork. According to actual climbing formwork in the super high-rise office building of Wanda Plaza in Kunming, China, the finite element model of the climbing formwork is established on the Ansys platform. The correctness of the model is verified by comparing the natural frequencies of the actual climbing formwork and the finite element model. The time-history analysis of the climbing formwork subjected to earthquakes of varying strong magnitudes is carried out. The maximum displacement position and maximum von Mises stress position of the climbing formwork under different working conditions are determined, and the seismic response of the climbing formwork is analyzed. It has been found that when the formwork is under construction, the maximum displacement position of the climbing formwork is at the center of the long beam of the upper platform, and the maximum von Mises stress position is the joint of the outer pole of the main platform and tripod. Under the climbing condition, the maximum displacement position of the climbing formwork is at the top of the outer pole of the upper platform, and the maximum von Mises stress position is the joint of the beam of the tripod and guide rail. The climbing formwork is partially damaged under the simulated earthquake. However, the displacement is large, and some components have reached the yield state. It is recommended to strengthen the connection between the upper platform and the guide rail and enhance the strength and rigidity of the outer pole and tripod. Climbing formwork is more sensitive to horizontal earthquakes and has minimal sensitivity to vertical earthquakes. The structure attached to the climbing formwork will reduce its sensitivity to earthquakes. The research results are of practical significance for seismic design and improvement of climbing formwork.

Economic performance analysis of seismic isolation, energy dissipation, and traditional seismic structures

The construction of a new countryside requires a compr hensive improvement in the building standards of villages and towns, and the seismic resistance of buildings in earthquake-prone areas has attracted much attention. Due to the backward economic development of villages and towns, the development of seismic isolation structure and energy dissipation structure is hindered. To build houses with better seismic performance, the economic efficiency of seismic isolation and energy dissipation structures has become a matter of close concern to the local people and the government. This article compares the economic differences between the original seismic structure, the base isolation structure, and the seismic damping structure from the costs incurred during the entire life cycle of the building, and provides economic reference for the new rural seismic isolation building.

Influence of the Floor Diaphragm on the Rocking Behavior of CLT Walls

In the design of cross-laminated timber (CLT) buildings in earthquake-prone areas, a crucial role in energy dissipation is played by the panel-to-panel joint. Such a connection, theoretically, could be designed for three different types of behavior: coupled, uncoupled, and monolithic. Coupled and uncoupled behaviors provide a certain amount of energy dissipation, whereas monolithic behavior does not. Currently, no specific design rules to attain a given condition are provided in any code. Furthermore, no information on the dependency of the wall behavior upon other variables, such as the out-of-plane stiffness of the floor diaphragms or the stiffness of other metal connections (e.g., hold-downs and angle brackets) can be found in the literature. In an attempt to fill in this gap, this paper presents the results of numerical analyses carried out using a commercial software package. In these analyses, the influence of the upper floor diaphragms on the rocking behavior of a two-panel wall assembly is investigated. Fully reversed displacement-controlled cyclic tests are simulated, while varying the geometrical properties (aspect ratio of the wall panels), mechanical properties (types and number of connectors used for the panel-to-panel, wall-to-foundation and wall-to-upper floor connections, out-of-plane stiffness of the floor panels), and gravity load applied on top of the assembly. The rocking capacity of the walls is investigated, together with displacements and global behavior of the assembly. The results obtained highlight the important role played by the stiffness of wall-to-floor diaphragm joints, whereas the out-of-plane flexural stiffness of the slab has a negligible effect on the overall response of the assembly.

Seismic Vulnerability and Retrofit Alternatives for Typical Soft-story Buildings in Earthquake Prone Areas

More than 300 buildings were severely damaged during the 19 September 2017 earthquake (Mw = 7.1) occurred in Morelos, Mexico. One of the most common structural deficiencies detected was the use of ground level parking that produced soft-story buildings. These structures suffered severe damaged or collapsed. A field visit after the earthquake allowed to collect information about typologies of the damaged buildings and a great number of seismic ground motions. This study analyzes the seismic capacity and demands of typical existing building with a soft-story structure, based on the information collected in Mexico City, and subjecting the building to a family of real accelerograms recorded in this area during the earthquake occurrence. To enhance the seismic capacity of these structures, and to reduce their seismic vulnerability, a retrofit technique based on the addition of energy dissipation devices is analyzed. Results show the most efficient retrofit techniques and the strength and stiffness parameters required to improve the expected seismic behavior of this type of structures, and their applicability to mitigate damage in future earthquakes.

Performance-Based Seismic Design of High-Rise Buildings: Incorporating Nonlinear Soil-Structure Interaction Effects

This project aims to understand better how to incorporate nonlinear soil-structure interaction (SSI) effects into high-rise building performance-based seismic design approaches. The primary goals are to determine how important it is to include nonlinear SSI effects, create integration methods for them, and analyze how they affect seismic resilience. In terms of methodology, the study uses case studies and an analysis of current literature to show real-world applicability. Important discoveries highlight how critical nonlinear SSI analysis is for precisely forecasting structural reactions, locating weaknesses, and creating focused mitigation strategies. The policy implications emphasize the necessity of modern building regulations, research and development expenditures, and advancements in site characterization methods to facilitate the implementation of performance-based design methodologies. To improve the resilience and safety of high-rise buildings in earthquake-prone areas, this study's findings highlight the significance of considering nonlinear SSI effects during seismic design procedures.

Pemeriksaan Material pada Pembangunan Rumah Non-Engineered di Daerah Rawan Gempa Dusun Serut, Palbapang Kabupaten Bantul, Yogyakarta

Bantul Regency is a region with high level of seismic activity in Indonesia. Buildings that have the highest risk of collapse to earthquake are non-engineered buildings or residential buildings built without planning or not according regulation. This study aims to know contruction practices and material examination on non-engineered buildings in earthquake prone areas in accordance with the Indonesian National Standard. The object research is the construction of non-engineered building in Serut Village, Palbapang, Bantul Regency. The testing of material construction materials include: concrete test, reinforcing steel test and bricks test. the material are tested on the laboratory of Universitas Muhammadiyah Yogyakarta. The observations and measurements to the practices of construction consist of: concrete sloof with size 15 × 20 cm with the main reinforcement 4O12 and beugel reinforcement O6-150; column with size 10 × 15 cm with main reinforcement 4O10 and beugel reinforcement O6-150; the concrete mixture is made manually with a composition 1 cement: 3 sand: 2 gravel; Brick size 4.35 cm x 12.036 cm x 23.902 cm class criteria M-6 module. Laboratory material test results showed: steel reinforcement diameter O 10 mm obtained tensile strength (fy) 401.52 Mpa; O12 mm diameter obtained tensile strength (fy) 393,736 M.Pa; concrete have average compressive strength of 181 kg/cm 2 ; brick test have average compressive strength of 20.03 kg/cm 2 . The conclusion of contruction practices on non-engineered buildings in earthquake prone areas are adequate on major earthquake, the quality of construction concrete and reinforcing steel are fulfilling the criteria and requirements of the Indonesian National Standard, but quality of material brick is not adequate standar.