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A variety of materials, including waste and rubber products, have been used in road construction to improve the performance of bituminous pavements. The present investigation is focused on modifying bitumen using Nitrile rubber (NBR) with different thermosets namely Bakelite (B), Furan Resin (FR), and Epoxy resin (ER). The emphasis of the problem is to arrive at a mix to achieve maximum Marshall Stability (MS) and minimum flow value of Modified Bituminous Concrete. Taguchi DOE technique has been used to design the experiments using Minitab software. Analysis of Variance (ANOVA) and Multi-objective optimization has been performed using the desirability approach in Design expert software. ANOVA analysis predicts that NBR, B, ER, and FR are the major significant parameters for Marshall Stability (MS) and Flow Value (FV). It has also been analyzed from SEM and EDS images of modified bitumen that sample S1 (5% NBR, 10% Bakelite, 10% FR, 2.5% ER) has a fine surface with small pores as compared to sample S34 (10% NBR, 0% Bakelite 10% FR, 2.5% ER). Multi-optimization results suggested the optimal conditions are achieved at NBR-7.6%, Bakelite-4.8%, FR-2.5%, and ER-2.6% for MS and FV. The maximum MS is 14.84 KN and the minimum FV is 2.84 mm is obtained using optimum conditions. To validate the optimization results, the confirmation runs have been conducted, and obtained results are within 5% error with optimal conditions.

e12099 Background: The purpose of this retrospective case series was to assess pCR rate, progression-free survival and prognostic factors in TNBC. Methods: We reviewed medical records for 33 consecutive female patients with TNBC (41% node+) treated between July 2015 and April 2018 with neoadjuvant paclitaxel 80 mg/m2 IV weekly plus concurrent carboplatin (AUC 4) every 3 weeks for a total of 12 weeks followed by dose-dense doxorubicin 60 mg/m2 plus cyclophosphamide 600 mg/m2 every 2 weeks for a total of 4 cycles. Surgical pathology was studied to determine the presence or absence of residual disease at surgery. Age at treatment, tumor stage, subsequent hospitalizations, and genetic testing were recorded. Patients with residual disease were treated with adjuvant capecitabine 1500 mg PO BID, one week on, one week off, for 6 monthly cycles ± radiation; some patients with a complete pathological response also received postoperative radiation. Results: Among 33 patients, 17 patients had pCR (52%, median age 58 yrs), 10 had a partial response and 6 had no response or progression (median age 63.5). After surgery 24 patients received radiation therapy (XRT). There were 6 hospitalizations, 3 that were treatment related, 2 for neutropenic fever and one for renal failure induced by carboplatin; all 3 resulted in chemotherapy dose reductions; all 3 had pCR. 3 progressions/recurrences were recorded: 2 after treatment and 1 progression during treatment. Two deaths occurred, 1 secondary to progressive disease. Median progression free survival time was 8.5 months (range 0.1 to 24.0 mos). Median time since diagnosis is 16.7 months (range 8.1 to 37.6 mos). There was no significant difference in the median age of patients who had a pCR compared with patients with residual disease. Conclusions: We observed pCR in patients with TNBC treated with a pre-operative carboplatin-containing regimen (superior to historical pCR rates in patients receiving taxanes and anthracyclines only). Although there are insufficient data to demonstrate increased overall survival, we show an improvement in prognosis with a carboplatin-containing regimen for TNBC.

This paper provides an analytical Solutions and software-based analysis on the determination of Stress-Strain behaviour of High strength concrete pavement slab by applying number of axle load parameters given in the guideline of IRC-58 in the construction of Rigid pavement. The effect of the use of hybrid fibres, such as steel fibres and polypropylene fibres, on the behaviour of stress distribution is also studied. Shrinkage in HSC due to the incorporation of Hybrid fibres in different proportions at four Curing Temperatures is also analysed. FEA has been used to analyse the Shrinkage behaviour of High Strength Concrete Pavements with different geometry and thermal curing temperatures as (5°C, 20°C, 35°C, and 50°C). In the present research, the shrinkage analysis, Stress distribution behaviour in High Strength concrete pavement will be studied using Hybrid fibre of steel and polypropylene with a dosage of 1%, 1.5% and 0.1%, 0.2% respectively and by applying axle loadings of single, dual, tri and tandem axle as per IRC 58. Axle load is applied at the centre, edge and corner of the pavement slab and the stress distribution results are obtained. The Analytical solutions are obtained from Westergaard’s equations and software-based results are compared with the analytical solutions and there are very less dissimilarities between both the results.

Quarry dust is considered as a possible source of natural sand or fine aggregate in concrete construction work. This could reduce the problem of dumping of quarry dust as a byproduct from stone crusher factory. The experimental work investigates the optimum quarry dust percentage which can be adopted as replacement of fine aggregate in concrete mainly for rigid pavement. The quarry dust is added at different percentages of 0%, 20%, 40%, 60%, 80%, and 100% replacement of fine aggregate for M35 grade concrete thereby to find out the optimum content of quarry dust that can give better strength in concrete. Mix design has been developed for M35 grade of concrete as per IRC 044 – 2017(Mix Design for Concrete Pavement) and mix design ratio is found as 1: 1.6: 2.62 by using Sulfonated naphthalene formaldehyde (SNF) as an admixture at 1%, and 2%. The required water cement ratio was obtained as 0.39 according to table no.9 of IRC 044 for the target strength of 42.5 N/mm2. Optimum strength and workability test values of concrete made up for various proportions of quarry dust along with SNF are compared with conventional concrete of natural fine aggregate after 7 days and 28 days curing. It is found that the strength increased with the increase in curing time and the maximum strength at 28 days curing and 60% quarry dust replacement with 2% addition of SNF. The maximum strength of quarry replaced concrete is obtained as 40.3MPa, 5.6MPa, and 5.1MPa for compressive, flexural, and split tensile respectively.