The Effects of Floor Structures on the Masonry Walls of Multistorey Building

In this contribution, the determination of loading forces in the joint of the floor structure and masonry is presented. The point is a subject being accompanied by designing multistorey masonry buildings.The problem of this apparently simple assignment is not so much a calculation of values from characteristic loading of both floors and walls or an actual numerical calculation of masonry carrying capacity, but a correct stipulation of the resultant force location at the spot under the floor structure.In the paper, the resting types of reinforced concrete floor structure on the masonry, influences on the resultant force magnitude, its position to the mid-masonry and consequences for the masonry construction design. The resting examples of floor structures, exhibitions of calculation, and schemas are given. Auxiliary tables and charts to specify the moments in the head of masonry were made up. In conclusion, a recommendation to the optimal span of floor structure destined for masonry construction is stated.

An In-depth Analysis for Optimal Cable Tray Support Span

Nowadays, it is crucial to reduce the cost of the overall project so that the competitiveness of offshore oil and gas without compromising on quality or safety can be achieved. This study investigates how to define the longest cable tray support span considering constructability in order to reduce the number of supports which is a chief cost of a cable tray system. This study presents not only material and geometry frequently used for cable tray but also the formula to estimate the maximum cable load which can be installed within cable tray. To verify the longest span without increasing the strength(thickness) of cable tray, finite element modelling approach was employed based on ANSYS and comparisons were made between numerical analysis and simplified hand calculation. The constructability for the longer span obtained from finite element analysis has been validated in view of manual handling of the cable tray. It is shown that the optimal span suggested in this paper can lead to a better economic benefit without degrading the constructability. For instance, as the span is longer, the cost of material as well as construction manpower can be saved. It is also expected that this approach will contribute to enhance the competitiveness of offshore oil and gas.

Optimal Span between Feet of Public Squat Toilet Based on Anthropometric Data and Squatting Stability Assessment

Sitting toilets are preferred globally because they afford a relatively comfortable posture. However, squat toilets are among the most common toilets in numerous public areas because of their advantages, including personal hygiene, easy cleaning, and health benefits. This study attempted to determine optimal toilet design parameters and recruited 50 Taiwanese and 50 Southeast Asian women and collected span between feet (SBF) data for participants squatting in their most comfortable posture, and also surveyed maximum outer width (MOW) data of 28 public squat toilets in Taipei. Finally, we compared the squatting stability levels of 40 female participants (20 Taiwanese and 20 Southeast Asians) who squatted for 2 min at comfortable SBF and MOW-based SBF values. The results revealed that the minimum and maximum SBFs of Taiwanese were 14.52 cm and 18.40 cm, and that of Southeast Asians were 15.64 cm and 20.40 cm, respectively. No significant difference was observed in the SBFs between the two groups was observed. The mean (range) MOW of the surveyed toilets was 27.7 (27–29) cm. Analysis of variance results showed no difference in stability between the two SBFs. This implies that the comfortable SBF (i.e., 16 cm between the participants’ heels) was narrower than the MOW, as commonly used, indicating that the comfortable SBF can be considered as an optimal toilet width parameter because of its constant stability.

RNA Secondary Structures with Limited Base Pair Span: Exact Backtracking and an Application

The accuracy of RNA secondary structure prediction decreases with the span of a base pair, i.e., the number of nucleotides that it encloses. The dynamic programming algorithms for RNA folding can be easily specialized in order to consider only base pairs with a limited span L, reducing the memory requirements to O(nL), and further to O(n) by interleaving backtracking. However, the latter is an approximation that precludes the retrieval of the globally optimal structure. So far, the ViennaRNA package therefore does not provide a tool for computing optimal, span-restricted minimum energy structure. Here, we report on an efficient backtracking algorithm that reconstructs the globally optimal structure from the locally optimal fragments that are produced by the interleaved backtracking implemented in RNALfold. An implementation is integrated into the ViennaRNA package. The forward and the backtracking recursions of RNALfold are both easily constrained to structural components with a sufficiently negative z-scores. This provides a convenient method in order to identify hyper-stable structural elements. A screen of the C. elegans genome shows that such features are more abundant in real genomic sequences when compared to a di-nucleotide shuffled background model.

Komparasi Biaya Konstruksi Bangunan Atas Jembatan Slab On Pile di Atas Tanah Lunak untuk Beberapa Variasi Bentang

Jembatan tipe slab on pile umumnya terdiri dari dua bentang atau lebih. Sampai saat ini belum ada ketentuan atau pedoman terkait dengan panjang bentang terkecil dan terbesar. Dengan demikian penentuan panjang bentang jembatan slab on pile lebih kepada engineering judgment desainer dan/atau pemilik jembatan. Penelitian ini mencoba menentukan panjang bentang optimal yang dapat menghasilkan biaya konstruksi bangunan atas yang minimal dalam satuan rupiah per satuan luas jembatan slab on pile di daerah tanah lunak. Adapun lokasi penelitian berada di Jembatan Ray 2 Kabupaten Barito Kuala. Dalam penelitian ini, jembatan dibagi kedalam tiga tipe, yaitu Tipe I dengan bentang segmental 4 m dengan banyak bentang lima bentang dan panjang bentang total 20 m, Tipe II dengan bentang segmental 5 m dengan banyak bentang empat bentang dan panjang bentang total 20 m, dan Tipe III dengan bentang segmental 7 m dengan banyak bentang tiga bentang dan panjang bentang total 21 m. Berdasarkan hasil desain, biaya konstruksi bangunan atas per satuan luas untuk untuk jembatan slab on pile tipe I sebesar Rp5,795,673.4, jembatan slab on pile tipe II sebesar Rp5,313,707.8, dan jembatan slab on pile tipe III sebesar Rp4,925,033.0. Perbedaan biaya konstruksi ini dipengaruhi oleh jumlah pier head yang dimiliki jembatan, dimana tipe III memiliki jumlah pier head terkecil Abstract Slab on pile bridges consist of two spans or more. Until now, there are not codes state cleary about shortest and largest span of slab on pile bridge. Therefore, decision about length of span tends to engineering judgement of designer and/or owner of the bridge. This research tries to propose about optimal span that obtain a minimal construction cost of superstructure of slab on pile bridge on soft soil area in rupiah per square area. This research is located at Ray 2 Bridge in Barito Kuala District. In this research, bridge classifies in three types: type I (4 m segmental length, 5 spans, and 20 m total span length), type II (5 m segmental length, 4 spans, and 20 m total span length), and type III (7 m segmental length, 3 spans, and 21 m total span length). According to design results in this research, construction cost of superstructure for type I, II, and III are Rp5,795,673.4, Rp5,313,707.8, and Rp4,925,033.0. construction cos differs among types because the numbers of pier head, wherein type III has smallest number of pier head

Analysis and Optimization for the Dynamic Characteristics of Drilling & Boring Machine Spindle System

Taking the spindle system of CNC drilling and boring machine that exclusively used in the latest developed bearing cage as study subject, this paper investigates the optimization of the spindle system by improving the support bearing structure and optimizing the spindle span to get the optimal span. Through modeling analysis, the fundamental frequency of the optimized spindle increase 16.9%, which provides effective-proof performance optimization.

Optimal Design Analysis of Prestressed Composite Space Truss

More than 40 prestressed composite space truss models of different dimensions are built with APDL design language, and the span, height, lattice number, prestressed value, section area of the chord, width and height of ribbed beam are chosen as design variables. With selecting total cost as objective function, constraint conditions such as strength, rigidity, stability, section size, prestressed limit and structural deflection are also considered, we conduct optimal design for structures by means of zero order optimization. From the results of regression analysis, the optimal span-to-height ratio, lattice number and empirical formula of optimal prestressed value can be found out for designers’ references.