Dynamic Performance on Multi Storey Structure Due to Ground Borne Vibrations Input from Passing Vehicles

Ground borne vibration from passing vehicles could excite the adjacent ground, hence produces a vibration waves that will propagate through layers of soil towards the foundations of any adjacent building. This vibration could affects the structure of the building at some levels and even the low sensitivity equipment are also could be affected as well. The objectives of this study are to perform the structural response on multi storey building subjected to ground vibrations input and to determine the level of vibration at each floor from road traffic on the observed building. The scopes of the study are focused on the groundborne vibrations induced by the passing vehicles and analyse the data by using dynamic software such as ANSYSv14 and MATLAB. The selected building for this study is the Registrar Office building which is located in Universiti Tun Hussein Onn Malaysia (UTHM). The inputs of the vibration were measured by using Laser Doppler Vibrometer (LDV) equipment. By conducting the field measurement, a real input of ground borne vibration from the loads of vehicle towards any adjacent building can be obtained. Finally, the vibration level from road traffic on office building can be determined using overseas generic criteria guidelines. The vibration level achieved for this building is at above the ISO level, which is suitable for office building and within acceptable limit

Vibration Criteria Assessment due to Piling Works

In the recent years, the level and nature of the ground vibrations has been more concerned in worldwide. Vibration affected on surrounding building is often associated with the vibration from the ground that is mainly caused by internal and external sources. One of the external sources is construction activities. Identify the effects of vibration caused by piling works in construction sites was the purpose of this paper. It is also aiming to determine the vibration criteria due to piling works in Klang Valley construction site. In addition, the objective of this study is to compare the level of vibration with Department of Environment (DOE) guideline between both Kajang MRT and Klang Valley MRT construction sites. The data used for this study is obtained from past researchers and field testing is performed by using Polytec Laser Doppler Vibrometer and Rion VM-55. The data has been analyzed by using ModalV of MATLAB software. Based on the results, it can be concluded that the vibration amplitude for three distance includes 5m, 10m and 20m are located above the ISO level which stated that the area within the distances not suitable for placement of sensitive equipment.  The highest value of root mean square velocity is occurred in the distance of 5m and the reading is 80000 µm/s. According to Department of Environment (DOE) guidelines, the vibration at distance of 1m and 3m at Kajang MRT will cause major damage to surrounding buildings while minor damage was produced by the vibration at 5m, 10m and 20m distance from bored piling point which located around the area of Klang Valley MRT

Vibration Assessment on Various Distance to Demolition Works

Vibration has been a serious problem to be discussed over the past years. Vibration has caused cosmetic damages to buildings and annoyance to the occupants of the building. Sources of vibration are usually produced by construction work, traffic, seismic effect and human activities. In this paper, the amplitude of vibration caused by demolition has been analyzed and the level of vibration and level of damage caused have been determined. Besides, the effect of the vibration strength due to distance from the source has also been studied. The vibration data due to demolition work was obtained and analyzed by using MATLAB software. The analyzed data in graphical form were compared with the Gordon vibration criteria to obtain the vibration limit and the level of vibration damage according to DOE (Malaysia) standard as well. The results indicated that the vibration at 1m distance and 10m distance from the vibration source will cause minor damage to the building whereas the vibration at 25m distance from the source is at the caution level. By comparing the Gordon vibration criteria curve, the vibration from 1m, 10m and 25m distance from the demolition vibration source are not suitable for sensitive equipment. This study also proved that the vibration strength will decrease as the distance from the source increases due to the loss of vibration energy during the propagation of vibration waves. Hence, the further the distance from the source, the weaker the strength of the vibration and lower level of damage on surrounding buildings

Assessment and optimisation of human walking and traffic induced vibration of floors in office buildings

Rapid development in office building construction and advanced technologies installed in sensitive structures such as high-tech equipment leads to requirements for very low levels of vibration and become more important in structural design. Therefore, this thesis presents an investigation of vibration criteria assessment and optimisation of the effect of low amplitude ground vibrations induced by human walking and traffic on the floors in office building. Two office buildings were chosen as the case study at two different places namely OB1 and OB2. Field measurement was carried out by using Laser Doppler Vibrometer (LDV100) to obtain vibration inputs. Vibration inputs were transferred into finite element analyses by using ANSYSv14 to simulate the structure dynamic response. MATLAB software also utilized to perform Vibration Criteria (VC) curve and plot. The results obtained were then checked against the generic VC curve from Gordon and Malaysia guidelines, to determine the vibration sensitivity level of each building. As a result, OB1 indicated under VC-A level due to vehicles at Singapore and OB2 at Malaysia fall under VC-E due to vehicles and increased to VC-C, VC-A and ISO level due to peoples walking. It is also showing which location on floor is suitable to accommodate the sensitive equipment, but not at the middle of the floor because of the peak response. After the modification process on structural elements such as slab thickness, beam and column sizes, and adding extra elements, the vibration response also changed either increased or decreased from the earlier VC curve and plot. OB1 shows almost similar vibration level under VC-A. While for OB2, it is also indicating similar response under VC-E. Therefore, from the iterative process in finite element modelling from the optimisation method, a VibroTable is proposed to be a new guideline or quick review to the client or structure analyst engineer to investigate the proper size of certain element of structure. The difference of vibration velocity values between Gordon and Malaysian guidelines were found, where Gordon guideline covers very low level of vibration effect, while Malaysian guideline only considers high level of vibration

A Study of Building Structure Resilience to Seismic in the Batu Pahat Area using Rapid Visual Screening Method

This study is aimed at evaluating the durability of buildings in Batu Pahat area against seismic activity. To carry out this assessment, data about the building structure is collected, including architect plans, site investigations, and photos. This data is then processed and analysed using manual methods. To determine the Peak Ground Acceleration (PGA) value, the coordinates of Batu Pahat area are needed. This value can be calculated using Mathematica software, which gives a PGA value of 0.0553 g for Batu Pahat area. Based on this value, the Low Map Area form is used for the evaluation, using the ATC-21 form. The evaluation results indicate that 70% of the buildings in the area are in good condition, 25% are in a satisfactory condition, and only 5% are in a weak condition. However, it is important to note that even though only a small percentage of buildings are classified as weak, it does not mean that seismic hazards can be ignored. The study also suggests that the durability of building structures depends on various factors, such as the columns' strength, the building's bottom situation (e.g., empty space or unit), the building's shape (e.g., plan or upright), and the surrounding area's situation. Overall, this study offers valuable insights into the durability of buildings in the Batu Pahat area against seismic activity. It provides crucial information for stakeholders to make informed decisions regarding building safety in the region. The study's findings will guide decision-making processes, helping determine necessary precautions, retrofitting measures, or potential relocation of high-risk buildings. By enhancing the resilience of buildings, this evaluation contributes to the safety and well-being of occupants in the face of seismic hazards. Ultimately, the study's comprehensive assessment and subsequent insights lay the groundwork for informed decision-making and proactive measures to mitigate seismic risks, benefiting the overall resilience of buildings in the Batu Pahat District