Suhaimi Abu Bakar

EXPERIMENTAL INVESTIGATION OF TSUNAMI WATERBORNE DEBRIS IMPACT ON STRUCTURES

Tsunamis and hurricanes cause a lot of damage to structures. The water-borne debris that is produced during these natural disasters can cause a considerable damage to the many structures if they have not been constructed for such loads. Tsunami field survey observations have indicated that the damage is aggravated by heavy objects like wooden logs, automobiles, boats, storage barrels and other containers. This paper presented the results of experimental study for the quantification of the debris impact force on the structures. Moreover, it studied the formulas, which have been specified in the recently published tsunami- resistant engineering design guidelines (FEMA P-646, 2012) and the Coastal Construction Manual (FEMA P- 55, 2011) with the results of experiment.

A Stochastic Simulation Framework for the Prediction of Strategic Noise Mapping and Occupational Noise Exposure Using the Random Walk Approach

Strategic noise mapping provides important information for noise impact assessment and noise abatement. However, producing reliable strategic noise mapping in a dynamic, complex working environment is difficult. This study proposes the implementation of the random walk approach as a new stochastic technique to simulate noise mapping and to predict the noise exposure level in a workplace. A stochastic simulation framework and software, namely RW-eNMS, were developed to facilitate the random walk approach in noise mapping prediction. This framework considers the randomness and complexity of machinery operation and noise emission levels. Also, it assesses the impact of noise on the workers and the surrounding environment. For data validation, three case studies were conducted to check the accuracy of the prediction data and to determine the efficiency and effectiveness of this approach. The results showed high accuracy of prediction results together with a majority of absolute differences of less than 2 dBA; also, the predicted noise doses were mostly in the range of measurement. Therefore, the random walk approach was effective in dealing with environmental noises. It could predict strategic noise mapping to facilitate noise monitoring and noise control in the workplaces.

Utjecaj poprečnih zidova na popustljivost stropne ploče

Krutost stropne ploce ima znacajan utjecaj na odgovor konstrukcije. Uobicajena je pretpostavka da se radi o krutom elementu. Ovakva pretpostavka smanjuje stupanj slobode i osigurava laksu analizu. No, tijekom posljednjih potresa, popustljivost stropne ploce privukla je znatiželju znanstvenika. Kako bi se istražilo njeno ponasanje, u ovom radu analizirana je jednokatna armiranobetonska konstrukcija. Analiza je provedena na cetiri okvirne konstrukcije, a primjenom racunalnih programa ETABS2000 i LUSAS je izracunat optimalni omjer između popustljivosti stropne ploce i pomaka konstrukcije. Analiza je pokazala da se kod omjera manjeg od 0,5 stropne ploce mogu razmatrati kao kruti element.

A Simple Algorithm to Assess Structural Performance by PBSD Method

In recent decades Performance Based Seismic Design (PBSD) is widely used for evaluation of the structural performance because of its capability and simplicity to estimate inelastic response of structure. On the other hand, some times in construction based on architectural decision, size of beams are being decreased. The aim of this attempt is to investigate the effect of beam size on structural behavior based on PBSD method using simple procedure. Capacity Spectrum Method (CSM) was implemented using set of RC frames (2, 4, 6, 8 and 10 story with three bays) and ETABS2000 to determine the weakness of the frames system due to their reduced beam size. The performance of the frames was measured at Life Safety damage control level.