Earthquake Performance Analysis of Steel Structures with A3 Plan Irregularities

In earthquake engineering, a performance-based design method is used to determine the level of the expected performance of the structures under the earthquake effect. The level of performance is related to the damage situation that could be occurred in the structure after the earthquake. In the performance-based structural design, it is predicted that more than one damage levels emerge under one certain earthquake effect. In this study, the seismic behavior of steel structures with plan irregularities in the Turkey Building Earthquake Code in the 2018 (TBEC-2018) is investigated by the nonlinear static analysis methods. The selected steel structures are located in İzmir, Turkey. The Turkey Earthquake Code in 2018 is considered for assessing seismic performance evaluation of the selected moment-resisting frame steel building. Four different A3 type irregularity was investigated. The steel building with no irregularity in its plan. was selected as the structure of the reference. The performance goals of the five different steel structures are evaluated by applying the pushover and procedures of the TBEC-2018. The steel structures were compared by obtaining pushover curves for both the X and Y directions. The results show that the effects of A3 type irregularity should be not considered in design and buildings without irregularities are safer.

Optimization of the Distance between Two Adjacent Multi-Story Buildings by Calculating the Earthquake Effect in Yogyakarta

Neo Malioboro and Malioboro Suite Hotels are two adjacent multi-story buildings in Yogyakarta with a fairly close distance of 2.5m (Lx) between their structures. Considering that Yogyakarta is an area prone to earthquakes, the relatively close distance between the two hotels has triggered research interest. The research was carried out by taking hotel planning data in the form of structural and architectural drawings modeled in SAP2000.14 to obtain structural behavior toward existing designs such as natural shear periods, base shear, mass participation, and to obtain deviation values between floors (drift ratio) and the center of mass deflection (δ). The largest deviation value of the two hotels in the joint reviewed occurred on the top floor, with the maximum deviation value of 0.440m (δM1) for Neo Malioboro and 0.412m (δM2) for Malioboro Suite. The minimum deflection distance between the two hotels was 0.602m (δMT), resulting in the minimum separation distance for the two hotels of 1.454m. The results revealed that the distance of the two hotels was in a safe condition because it was greater than the required minimum separation distance of 2.5m > 1.454m.

Lightweight Concrete With Mixed Foam Agent, Polymer and Bonding to Reach 300 Kg/Cm²

Lightweight concrete is very much developed because of its benefits that can reduce the weight of the building itself, so that the earthquake effect on buildings can be minimized. By using Foam Agent Technology, it will add air pores which can reduce the specific gravity of normal concrete. To achieve the K 300 Concrete Quality with Light Weight, the researchers added Polymer and Polymer and Bonding mixture to the Concrete mixture using Foam Agent technology. From the research conducted by researchers, it was found that Foam Agent is able to help concrete become lighter by 13%. This research was also able to obtain the optimum compressive strength results with a light weight, the Light Concrete study with the addition of Foam Agent, Polymer and Bonding with a quality of 267 kg / cm² or equivalent to Fc 22 with a weight of 1877 Kg / cm³ and an efficiency coefficient of 14% which is higher than normal Concrete K 300 with a magnitude of 13%.

Study on Seismic Absorption Performance of Assembled Shear Wall Structure under Pre-Stressed Constraint

In order to respond to the construction policy of "economy, application, green and beauty" put forward by China in the new period, the assembly structure has gradually become the focus of attention in recent years. Compared with the traditional cast-in-place structure, the assembled structure is more in line with the requirements of energy-saving, material-saving, environmental protection, etc. Therefore, it is of great importance to further study the seismic performance of assembled structures. However, existing assembled shear wall structures often suffer from problems such as the joint position is difficult to construct because of its wet work, and strong component weak nodes often appear. The seismic performance of the joints needs to be further studied and so on. Aiming to solve above problems, a new type of pre-stressed constraint assembled shear wall structure was proposed by us. The structure is connected by pre-stressed tendon to shear wall, and there is no wet operation at the construction site, which is conductive to improving construction quality. When the earthquake occurs, the structure can increase its self-shock period by changing its own stiffness, so as to reduce the earthquake stress. Meanwhile, many conditions to improve the ductility of the structure do not need to be considered, thus avoid the waste of steel materials. Based on the time history analysis of cast-in-place shear wall structure model and pre-stressed shear wall structure model, the results of calculation show that: compared with cast-in-place shear wall structure, the pre-stressed shear wall structure can effectively reduce the earthquake effect by about 90%.

Strengthening of Traditional Mud Houses on Response to Earthquake

Earthquake is an unexpected natural disaster that is unforeseeable and several earthquakes have been faced in Bangladesh with a magnitude of more than 6 in Richter scale in recent years. Non engineered houses are very common in rural area. Mudhouse is a typical house pattern among the non-engineered houses. The earthquake effect in conventional mud houses is a great concern. These houses are susceptible to earthquake damage due to some attributes of materials consisting of less stiffness, brittleness and poor bonding between the units. The present study deals with the strengthening of such houses using timber reinforcement with definite proportion contemplating the mud wall sizes and strengthening the walls by allowing some additional materials as reinforcements. Arrangements of reinforcement were followed in such a way that they would not require skilled labour and much cost. A finite element application STAAD-Pro was adopted to execute the required analysis of unreinforced and reinforced models considering both single story and double story. A series of analyses incorporating linear static and linear dynamic analyses were conducted to comprehend the actual response of models. Investigations from analyses depict that timber reinforcements impart greater stiffness and strength against overturning which increases the frequency of the structure and diminishes the lateral displacements to a good extent. The output from analyses includes lateral displacements, frequency, time-dependent displacements and time-dependent acceleration which depict the positive behaviour of reinforced mud houses. Such an arrangement of reinforcement can be a good choice to subside the detrimental effect of the earthquake.

Palelindon: Unravel the hidden meaning of earthquake

On the history of humanity, multiple approaches and methods have been conducted to determine reliable formula on predicting when and where the earth would release its seismic pulse. Many quests have been conducted for more than century to forecast the quake occurrence, yet failed to meet the expectation for long run prediction. Earthquake in a simple term is defined as convulsion on the earth’s surface. Based on its trigger, the quake could be classified into two namely seismic activity and tremor. A vast horseshoe area covers 40,000 km square in the shore of pacific ocean is notorious for its title as The Ring of fire (ROF); an area that has been experiencing continuous series of lithosphere seismic activities. Living within the geologically active area, Bali as part of Indonesia since ancient times seemed to experience multiple quakes. While most research relentlessly sought to predict the earthquake accurately, Balinese local wisdom claimed to be ably predicting the aftereffect of earthquake as compiled in Palelindon manuscript. The script proposed detailed explanation of earthquake effect on nature that subsequently affects human behaviour. This idea may seem as old myth, and could not be suggested publicly worldwide as scientific explanation. Balinese life is firmly bound by local belief and custom. Nevertheless, the text explanation occasionally is taken into account as precaution to prepare any upcoming upheaval on the island.

GIS-Based Rockfall Susceptibility Zoning in Greece

The assessment of rockfall risks on human activities and infrastructure is of great importance. Rock falls pose a significant risk to (a) transportation infrastructure, (b) inhabited areas, and (c) Cultural Heritage sites. The paper presents a method to assess rockfall susceptibility at national scale in Greece, using a simple rating approach and Geographic Information Systems (GIS) techniques. An extensive inventory of rockfalls for the entire country was compiled for the period between 1935 and 2019. The rockfall events that were recorded are those which have mainly occurred as distinct rockfall episodes in natural slopes and have impacted human activities, such as roads, inhabited areas, and archaeological sites. Through a detailed analysis of the recorded data, it was possible to define the factors which determine the occurrence of rockfalls. Based on this analysis, the susceptibility zoning against rockfalls at the national scale was prepared, using a simple rating approach and GIS techniques. The rockfall susceptibility zoning takes into account the following parameters: (a) the slope gradient, (b) the lithology, (c) the annual rainfall intensity, (d) the earthquake intensity, and (e) the active fault presence. Emphasis was given on the study of the earthquake effect as a triggering mechanism of rockfalls. Finally, the temporal and spatial frequency of the recorded events and the impact of rockfalls on infrastructure assets and human activities in Greece were evaluated.

GIS-Based Rockfall Susceptibility Zoning in Greece

The assessment of rockfall risks on human activities and infrastructure is of great importance. Rock falls pose a significant risk to a) transportation infrastructure b) inhabited areas and c) Cultural Heritage sites. The paper presents a method to assess rockfall susceptibility at national scale in Greece, using a simple rating approach and GIS techniques. An extensive inventory of rockfalls for the entire country was compiled for the period between 1935 and 2019. The rockfall events that were recorded are those, which have mainly occurred as distinct rockfall episodes in natural slopes and have impacted human activities, such as roads, inhabited areas and archaeological sites. Through a detailed analysis of the recorded data, it was possible to define the factors which determine the occurrence of rockfalls. Based on this analysis, the susceptibility zoning against rockfalls at national scale was prepared, using a simple rating approach and GIS techniques. The rockfall susceptibility zoning takes into account the following parameters: (a) the slope gradient, (b) the lithology, (c) the annual rainfall intensity, (d) the earthquake intensity and (e) the active fault presence. Emphasis was given on the study of the earthquake effect as a triggering mechanism of rockfalls. Finally, the temporal and spatial frequency of the recorded events and the impact of rockfalls on infrastructure assets and human activities in Greece were evaluated.