scholarly journals ANALISA PERBANDINGAN BIAYA DAN WAKTU PERKERASAN KAKU METODE CAST IN SITU (CIS) DAN METODE PRECAST PRESTRESSED CONCRETE PAVEMENT (PPCP) (Studi Kasus Pada Proyek Jalan Tol X Di Jawa Timur)

2014 ◽  
Vol 8 (2) ◽  
pp. 134
Author(s):  
Rakmat Dwi Anugrah Putra, Sugiharti
Keyword(s):  
Prestressed Concrete ◽  
Fresh Concrete ◽  
Precast Concrete ◽  
American Concrete Institute ◽  
Concrete Pavement ◽  
Rigid Pavement ◽  
Expected Time ◽  
Technical Drawing ◽  
The One

Concrete cracks on pavement occurred at X Toll Road implementation before the pavement attained the expected time. Consquently, it must be removed and it caused cost and time loss. CIS is a method in which fresh concrete is cured in site, and PPCP is the one in which the pavement is stressed by stretching the steel tendon and anchor into the fresh concrete before live load is applied.  The objective of the study is to compare method between the two from cost and time. California Bearing Ratio (CBR), technical drawing, daily passing vehicle rate, concrete, and itemized work cost were employed. National Association of Australian State Road Authorities (NAASRA) was employed to implement the rigid pavement; American Concrete Institute (ACI) was based on PPCP for the pavement depth design.The calculations result in 27 cm deep of CIS and 20 cm deep of PPCP; IDR 216.336.692.351,25   and 208 workday for CIS ; IDR 222.068.995.407,73 and 158 workdays for PPCPKeywords: cast in situ, cost and time, rigid pavement, prestressed precast concrete pavement

Comparison of Precast and Conventional Concrete Rigid Pavements Using Analytical Hierarchy Process (AHP)

2021 ◽  
Vol 26 (2) ◽  
pp. 212-219
Author(s):  
Nuroji Nuroji ◽  
Bagus Hario Setiadji ◽  
Wahyu Aktorina
Keyword(s):  
Analytical Hierarchy Process ◽  
Precast Concrete ◽  
Concrete Pavement ◽  
Traffic Load ◽  
Construction Time ◽  
Conventional Concrete ◽  
Rigid Pavement ◽  
Improvement Project ◽  
The Road ◽  
Hierarchy Process

The rigid pavement on many roads is considered as a solution due to the increasing traffic load that requires high performance and durability of the road construction. However, the implementation of rigid pavement takes a longer time to reach its concrete strength until the road operation. Some industries have developed pavement from precast concrete panels to reduce construction time. This paper discusses the comparison of rigid pavement between precast concrete and conventional concrete. Two road sections are Jalan Margomulyo Surabaya using precast-concrete-pavement and Jalan Semarang-Jambu using conventional-concrete-pavement chosen as research objects. Cost, construction time, serviceability, and traffic performance are the four variables reviewed in this study analyzed using the Analytical Hierarchy Process (AHP) method with considers 15 competent experts as respondents. Based on the analysis shows that a road improvement project by using precast-pavement is more effective and efficient with a score of 58.42 %, while the score of conventional concrete is 41.58 %.

scholarly journals Hysteretic Response of Tilt-Up Concrete Precast Walls with Embedded Steel Plate Connections

2020 ◽  
Vol 12 (19) ◽  
pp. 7907
Author(s):  
Hyun-Do Yun ◽  
Hye-Ran Kim ◽  
Won-Chang Choi
Keyword(s):  
Prestressed Concrete ◽  
Structural Integrity ◽  
Precast Concrete ◽  
American Concrete Institute ◽  
Steel Plates ◽  
Test Results ◽  
Wall Panel ◽  
Concrete Wall ◽  
Concrete Panels ◽  
Wall Panels

Many connection systems are available that can transfer tension and shear loads from a precast concrete wall panel to a floor slab. However, due to the insufficient anchor depth in relatively thin precast concrete panels, it is difficult to attain adequate ductility and stiffness to ensure structural integrity. Based on the authors’ previous research results, the supplementary reinforcement of embedded steel plates in precast concrete wall panels can enhance stiffness while maintaining allowable displacement and ductility. In this study, three full-size tilt-up precast concrete panels with embedded steel plates were fabricated. Lateral cyclic loads were applied to full support structures consisting of a precast concrete wall panel and a foundation. The test results were compared with the results predicted using existing code equations found in the American Concrete Institute 318-14 and the Prestressed Concrete Institute Handbooks. The test results confirm that the supplementary reinforcement of thin precast concrete wall panels can provide (i) the required strength based on current code equations, (ii) sufficient ductility, and (iii) the energy dissipation capacity to resist cyclic loading.

The Merivale Rail Bridge, Brisbane, Australia

1984 ◽  
Vol 11 (4) ◽  
pp. 673-684
Author(s):  
J. Snelling
Keyword(s):  
Key Words ◽  
Prestressed Concrete ◽  
Precast Concrete ◽  
Large Diameter ◽  
Bridge Foundations ◽  
Railroad Bridges ◽  
Steel Construction

The Merivale Rail Bridge crosses the Brisbane River and has as its main span a 132 m tied steel arch. The cable pattern is unusual and was derived to maximize the stiffness of the span under railway loading. The river foundations are large diameter piles formed from precast concrete "boats," which became the lower parts of the piers. This arrangement avoided underwater work and provided a robustness commensurate with shipping movements in the river. Approach spans are cast in situ prestressed concrete continuous viaducts except where clearance restrictions to existing roadways necessitated cast in situ prestressed concrete through bridges. Investigation, design, fabrication, and construction are described. Key words: railroad bridges, tied arch, steel construction, bridge foundations, prestressed concrete cables.

scholarly journals NIR responsive tumor vaccine in situ for photothermal ablation and chemotherapy to trigger robust antitumor immune responses

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Lirong Zhang ◽  
Jingjing Zhang ◽  
Lixia Xu ◽  
Zijian Zhuang ◽  
Jingjin Liu ◽  
...  
Keyword(s):  
Immune Responses ◽  
Tumor Vaccine ◽  
Oxidative Polymerization ◽  
Delivery Mode ◽  
Tumor Treatment ◽  
One Pot ◽  
Photothermal Ablation ◽  
Prolonged Retention ◽  
The One

Abstract Background Therapeutic tumor vaccine (TTV) that induces tumor-specific immunity has enormous potentials in tumor treatment, but high heterogeneity and poor immunogenicity of tumor seriously impair its clinical efficacy. Herein, a novel NIR responsive tumor vaccine in situ (HA-PDA@IQ/DOX HG) was prepared by integrating hyaluronic acid functionalized polydopamine nanoparticles (HA-PDA NPs) with immune adjuvants (Imiquimod, IQ) and doxorubicin (DOX) into thermal-sensitive hydrogel. Results HA-PDA@IQ NPs with high photothermal conversion efficiency (41.2%) and T1-relaxation efficiency were using HA as stabilizer by the one-pot oxidative polymerization. Then, HA-PDA@IQ loaded DOX via π-π stacking and mixed with thermal-sensitive hydrogel to form the HA-PDA@IQ/DOX HG. The hydrogel-confined delivery mode endowed HA-PDA@IQ/DOX NPs with multiple photothermal ablation performance once injection upon NIR irradiation due to the prolonged retention in tumor site. More importantly, this mode enabled HA-PDA@IQ/DOX NPs to promote the DC maturation, memory T cells in lymphatic node as well as cytotoxic T lymphocytes in spleen. Conclusion Taken together, the HA-PDA@IQ/DOX HG could be served as a theranostic tumor vaccine for complete photothermal ablation to trigger robust antitumor immune responses.

scholarly journals Two Separate Cases: Complex Chromosomal Abnormality Involving Three Chromosomes and Small Supernumerary Marker Chromosome in Patients with Impaired Reproductive Function

Genes ◽  
2020 ◽  
Vol 11 (12) ◽  
pp. 1511
Author(s):  
Tatyana V. Karamysheva ◽  
Tatyana A. Gayner ◽  
Vladimir V. Muzyka ◽  
Konstantin E. Orishchenko ◽  
Nikolay B. Rubtsov
Keyword(s):  
Genetic Counseling ◽  
Chromosome Rearrangement ◽  
Marker Chromosome ◽  
Reproductive Function ◽  
Small Supernumerary Marker Chromosome ◽  
Comprehensive Chromosome Screening ◽  
The Family ◽  
Multicolor Banding ◽  
The One

For medical genetic counseling, estimating the chance of a child being born with chromosome abnormality is crucially important. Cytogenetic diagnostics of parents with a balanced karyotype are a special case. Such chromosome rearrangements cannot be detected with comprehensive chromosome screening. In the current paper, we consider chromosome diagnostics in two cases of chromosome rearrangement in patients with balanced karyotype and provide the results of a detailed analysis of complex chromosomal rearrangement (CCR) involving three chromosomes and a small supernumerary marker chromosome (sSMC) in a patient with impaired reproductive function. The application of fluorescent in situ hybridization, microdissection, and multicolor banding allows for describing analyzed karyotypes in detail. In the case of a CCR, such as the one described here, the probability of gamete formation with a karyotype, showing a balance of chromosome regions, is extremely low. Recommendation for the family in genetic counseling should take into account the obtained result. In the case of an sSMC, it is critically important to identify the original chromosome from which the sSMC has been derived, even if the euchromatin material is absent. Finally, we present our view on the optimal strategy of identifying and describing sSMCs, namely the production of a microdissectional DNA probe from the sSMC combined with a consequent reverse painting.

Failure by corrosion in PC bridges: a case history of a viaduct in Italy

2016 ◽  
Vol 7 (2) ◽  
Author(s):  
Piero Colajanni ◽  
Antonino Recupero ◽  
Giuseppe Ricciardi ◽  
Nino Spinella
Keyword(s):  
Prestressed Concrete ◽  
Design Methodology ◽  
Progressive Collapse ◽  
Numerical Analyses ◽  
Existing Structures ◽  
History Of ◽  
Progressive Collapse Analysis ◽  
Practical Implications ◽  
Post Tensioned

Purpose The paper illustrates a viaduct collapse due to corrosion phenomena. Moreover, a contribution to the issues related to both the control of existing structures and design methods to be followed for the construction of new buildings is provided. Design/methodology/approach The objectives were achieved by in situ observations and numerical analyses. The effects of corrosion phenomena are investigated, and the progressive collapse analysis is provided to be helpful in this case. Findings The damages induced by corrosion phenomena have caused the collapse of the viaduct taken in to account. The performed numerical analyses were able to reproduce the effects of corrosion in terms of reduction of wires diameter. Research limitations/implications The research is limited to prestressed concrete viaduct with post-tensioned cables. Practical implications A monitoring plan, subdivided in several phases, is suggested, to avoid critical situations as these described. Originality/value The case study brought useful information on the effects of corrosion on the decks section, showing how the technology in post-tensioned cables is usually insidious and prone to the issues relating to corrosion of the wires

Observing microscopic phases of lichen life cycles on transparent substrata placed in situ

2005 ◽  
Vol 37 (5) ◽  
pp. 373-382 ◽  
Author(s):  
William B. SANDERS
Keyword(s):  
Life Cycle ◽  
Developmental Stages ◽  
Life Cycles ◽  
Potential Significance ◽  
Free Living ◽  
Lichen Community ◽  
One Year ◽  
The One ◽  
Observation Period

The utility of plastic cover slips as a substratum for in situ study of lichen developmental stages is further explored in a neotropical foliicolous lichen community and in a European temperate corticolous community. Twenty-one months after placement in the tropical forest, the cover slips bore foliicolous lichen thalli with several species producing characteristic ascocarps and ascospores, indicating the suitability of the substratum for completion of the life cycle of these lichens. On cover slips placed within the temperate corticolous community, lichen propagules anchored to the substratum with relatively short attachment hyphae but did not develop further within the one year observation period. Intimately intermixed microbial communities of short-celled, mainly pigmented fungi and chlorophyte algae developed upon the transparent substratum. Among the algae, Trebouxia cells, often in groups showing cell division and without associated lichenizing hyphae, were commonly observed. The potential significance of the free-living populations in the life cycle of Trebouxia and in those of Trebouxia-associated lichen fungi is discussed.

A Domino Heck Coupling–Cyclization–Dehydrogenative Strategy for the One-Pot Synthesis of Quinolines

Synthesis ◽  
2021 ◽  
Author(s):  
Santanu Ghora ◽  
Chinnabattigalla Sreenivasulu ◽  
Gedu Satyanarayana
Keyword(s):  
Functional Group ◽  
Exchange Process ◽  
Palladium Catalysis ◽  
Allylic Alcohols ◽  
Heck Coupling ◽  
One Pot ◽  
Synthetic Process ◽  
Intramolecular Condensation ◽  
The One

AbstractAn efficient, one-pot, domino synthesis of quinolines via the coupling of iodoanilines with allylic alcohols facilitated by palladium catalysis is described. The overall synthetic process involves an intermolecular Heck coupling between 2-iodoanilines and allylic alcohols, intramolecular condensation of in situ generated ketones with an internal amine functional group, and a dehydrogenation sequence. Notably, this protocol occurs in water as a green solvent. Significantly, the method exhibits broad substrate scope and is applied for the synthesis of deuterated quinolines through a deuterium-exchange process.

PCI Standard Design Practice Ref ACI 318-14

2021 ◽  
Author(s):  
Keyword(s):  
Prestressed Concrete ◽  
Precast Concrete ◽  
Building Code ◽  
Design Practice ◽  
Structural Concrete ◽  
Design Engineers ◽  
Standard Design ◽  
Precast Prestressed Concrete ◽  
Consistent Approach ◽  
Code Provisions

Precast, prestressed concrete design is based on conformance with the provisions of the American Concrete Institute’s (ACI’s) Building Code Requirements for Structural Concrete (ACI 318-14) and Commentary (ACI 318R-14). In most cases, these provisions are followed explicitly. Occasionally, interpretation of some sections of ACI 318 is required to ensure quality is maintained in conjunction with the unique characteristics of precast and prestressed concrete fabrication, shipping, and erection. Members of the PCI Building Code Committee, along with other experienced precast concrete design engineers, have identified code provisions, detailed in this publication, that require clarification or interpretation. These design practices are followed by most precast concrete design engineers to produce safe, economical precast concrete structures and they provide a consistent approach for the designers and contractors.

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