Ce-405-doe-complete (2).odt

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Major Design of Experiment (DoE) Experience Information CE 401 Soil Mechanics 2 nd Semester, SY 2018-2019 CALDERON, Perry Lee, Youngmin CASTRO, Jun-Jun ENTERESO, Mary Angel GERSANIVA, Ana Rose Lee, Youngmin MEDRANO, Jed Christian

Group Members Feasibility Study on Partial Replacement of Coarse Aggregates in Concrete using Construction Debris

DoE Title

Experimental Objectives

This DoE aims to: 1. Conduct an experiment to determine the feasibility of using construction debris as a substitute of coarse Design aggregates 2. Develop change in compressive strength of composite concrete 3. Discuss feasibility of using composite concrete in construction works.

Input Variables Load

It is a force, deformation, or acceleration applied to a structure or its components. In this experiment, it is a force exerted on specimen when specimen is under rupture failure. Percentage of replacement of The percentages of replacement are 0, 25,50,70, and 100% coarse aggregate Output/Response Variables Compressive Strength It is the capacity of a material or structure to withstand loads tending to reduce size, as opposed to tensile strength, which withstands loads tending to elongate Design Statistics Composite concrete (coarse aggregates is partially replaced with construction debris) showed significant development of compressive strength in stage of 7 and 14 days in compared with pure concrete. In 21 and 28 days, pure concrete was more dominant in terms of increase in compressive strength. Composite concrete was recessive rather in 21 days stage. Testing Standards (If Applicable) American Society of Testing ASTM C39 – this test method covers determination of compressive and Materials strength of cylindrical concrete specimens such as molded cylinders (ASTM) and drilled cores. American Institute of Concrete ACI 211.1-91 standard practice for selecting proportions for normal, (ACI) Standard Practice heavyweight, and mass concrete

Design of Experiment (DoE)

Feasibility Study on Partial Replacement of Coarse Aggregates in Concrete using Construction Debris

CALDERON, Perry Lee, Youngmin CASTRO, Jun-Jun ENTERESO, Mary Angel GERSANIVA, Ana Rose Lee, Youngmin MEDRANO, Jed Christian

Technological Institute of the Philippines Cubao, Quezon City

March 22, 2019

TABLE OF CONTENTS Feasibility Study on Partial Replacement of Coarse Aggregates in Concrete using Construction Debris TABLE OF CONTENTS.............................................................................................................................................i LIST OF FIGURES.....................................................................................................................................................i LIST OF TABLES.......................................................................................................................................................i I.

GENERAL BACKGROUND............................................................................................................................1

II.

DESIGN EXPERIMENTAL OBJECTIVES.......................................................................................................1

III.

EXPERIMENTAL PROGRAM.........................................................................................................................2

IV.

PROCEDURE (TESTING STANDARDS IF APPLICABLE)............................................................................3

V.

DESIGN STATISTICS.....................................................................................................................................4

VI.

DISCUSSIONS................................................................................................................................................5

VII. CONCLUSION AND GENERAL RECOMMENDATIONS................................................................................5 VIII. REFERENCES................................................................................................................................................6

• LIST OF FIGURES Figure 1 AGGREGATE WATER CONTENT ……………………………………………………………………2 Figure 2 FLOW CHART OF CONCRETE MIX DESIGN AND CURING ……………………………..……… 3 • LIST OF TABLES Table.1 ………………………………………………………………………………………. Table 2. …………………………………………………………………………………….

I. GENERAL BACKGROUND Huge quantities of construction materials are required in developing countries due to continued infrastructural growth and also huge quantities of construction and demolition wastes are generated every year in developing countries. The disposal of this waste is a very serious problem because it requires huge space for its disposal and it also pollutes the environment. Hence, It is necessary to protect and preserve the natural resources like stone, sand etc. the depth of river bed resulting in drafts and also changing the climatic conditions. Therefore, the sustainable concept should be introduced in construction industry due to growing concern about the future of our planet. The proportion of concrete rubbles is maximum in the demolition waste. Several researchers such as Hansen(1992); Mehta (1993); Collins (1994); Sherwood(1995); in their study, reveal that the crushed concrete rubble can be used as a substitute of natural coarse aggregates in concrete or as a sub-base or base layer in pavement, after separating these from the construction and demolition wastes. Some construction projects have been successfully completed using the recycled aggregates; This study aims to support aforementioned feasibility study of partial replacement of coarse aggregates using construction waste I. EXPERIMENTAL DESIGN OBJECTIVES This DoE aims to: 1) Conduct an experiment to determine the feasibility of using construction debris as a substitute of coarse aggregates 2) Develop change in compressive strength, flexural strength of composite concrete 3) Discuss feasibility of using composite concrete in construction works.

II. EXPERIMENTAL PROGRAM a. FRAMEWORK In making of concrete design, all the raw materials (i.e. cement, F.A. and C.A.) shall undergo physical tests for the properties (i.e. sieve analysis, unit weight, bulk specific gravity and absorption capacity) needed for mix design process. And the estimated weight of the concrete per unit volume was based from ACI method of concrete design. This method takes into consideration he requirements for consistency, workability, strength and durability. STEP 1: ESTIMATE CONCRETE We estimate concrete to attain the desired design stress for flexural and compressive also to measure the required materials that just needed in molds. Estimate also the admixture needed in your concrete design STEP 2: SIEVE F.A. AND C.A. We sieve fine and coarse aggregates for analyzing materials because particle size distribution can affect a wide range of properties such as the strength of concrete, the solubility of a mixture, and surface area properties. STEP 3: WEIGHING Based on computed weight proportion, weigh the individual dry materials. Aggregate volumes are computed based on oven dry unit weights, but aggregate is typically batched based on actual weight. Therefore, any moisture in the aggregate will increase its weight and stockpiled aggregates almost always contain some moisture. Without correcting for this, the batched aggregate volumes will be incorrect. STEP 4: MIXING If the batched aggregate is anything but saturated surface dry it will absorb water (if oven dry or air dry) or give up water (if wet) to the cement paste. This causes a net change in the amount of water available in the mix and must be compensated for by adjusting the amount of mixing water added.

FIGURE 1: AGGREGATE WATER CONTENT STEP 5: SLUMP TEST Slump test is performed by filling a slump apparatus mold of fresh concrete in three layers of each equal volume. Each layer is compacted with 25 strokes of a tamping rod. Slump mold is lifted vertically upward and the change in height of the concrete is measured.

STEP 6: MOLDING Fill the specimen mold in three layers of each equal volume and each layer is compacted with 25 strokes of tamping rod. Repeat and fill all other the specimen molds. STEP 7: CURING Place the concrete specimens in a room with constant temperature. After 24 hours of setting remove all the early hardened concrete from the mold and submerged in bath tub full of water for 7-28 days curing period. STEP 8: TESTING Test samples according to ASTM C39

FIGURE 2: FLOW CHART OF CONCRETE MIX DESIGN AND CURING b. ASSUMPTIONS AND LIMITATIONS Assumptions: 1) A composite mix of all the waste materials can be used as a replacement of C.A 2) ACI 211.1 – 91 can be used under the condition stated #3 assumption 3) It is assumed that a variety of construction debris’ properties such as dry-rodded unit weight, fine modulus, moisture content etc. are equal to ordinary coarse aggregates used in pure concrete Limitations: 1) Mixing concrete are done by hand mixing 2) Only one batch of example of compressive strength 3) 21 days old concrete beam specimen is not included

III. PROCEDURE

For application of ACI 211.1 -91 all the raw materials (i.e. cement, F.A. and C.A.) shall undergo physical tests for the properties Mixing and Curing 1) Sieve the fine and coarse aggregates and prepare all dry materials for weighing. 2) Based on computed weight proportion, weigh the individual dry materials. 3) The aggregate is spread in a uniform layer on a hand, clean and non-porous base. 4) Cement is then spread over the aggregates and the dry materials are mixed by turning over from one end to another until the mix appears uniform, turning three times is usually required. 5) Water is then gradually added so that water neither by itself nor with cement can escape. The mix is turned over again usually by three times, until it happens in color and consistence. 6) Slump test is now performed by filling a slump apparatus mold of fresh concrete in three layers of each equal volume. Each layer is compacted with 25 strokes of a tamping rod. 7) Slump mold is lifted vertically upward and the change in height of the concrete is measured. 8) Final fill the specimen mold in three layers of each equal volume and each layer is compacted with 25 strokes of tamping rod. Repeat and fill all other the specimen molds. 9) Place the concrete specimens in a room with constant temperature. After 24 hours of setting remove all the early hardened concrete from the mold and submerged in bath tub full of water for 7-28 days curing period. The test is repeated every seven day after the first testing 1) Placing the Specimen—Place the plain (lower) bearing block, with its hardened face up, on the table of the testing machine directly under the spherically seated (upper) bearing block. 2) Wipe clean the bearing faces of the upper and lower bearing blocks and of the test specimen and place the test specimen on the lower bearing block. 3) Carefully align the axis of the specimen with the center of thrust of the spherically seated block. 4) verify that the load indicator is set to zero 5) Rate of Loading—Apply the load continuously and without shock 6) Apply the compressive load until the load indicator shows that the load is decreasing steadily and the specimen displays a well-defined fracture pattern 7) Record data

IV. DESIGN STATISTICS a. ANALYSIS This chapter presents the test results of experiments. All data and information are tabulated for ease of interpretation. For this analysis, it is aimed that determination of compressive strength of concrete cylinders with 75% of coarse aggregates replaced with construction debris. Data and Results: Table 1. 75 % Concrete Trials

7

14

21

28

Compressive Strength

1878.242 psi

2609.23 psi

1826.028 psi

2375.222 psi

Trials

7

14

21

28

Compressive Strength

1868.08 psi

1875.34 psi

2230.68 psi

3111.06 psi

Table 2. 100% Concrete

Appendix: Cement: The most common used cement is Portland. It should be dry, powdery and free of lumps. When storing cement try to avoid all possible contact with moisture. Store away from exterior walls, off damp floors, and stacked close together to reduce air circulation. Water: In general, water fit for drinking is suitable for mixing concrete. Impurities in the water may affect concrete, setting time, strength, shrinkage or promote corrosion of reinforcement. Sand: Sand should range is size from less than .25 mm to 6.3 mm. Sand from sea shores, dunes or river banks is usually too fine for normal mixes. However, you can sometimes scrape about 30 cm of fine surface sand off and find coarser, more suitable sand beneath. Gravel: Optimum gravel size in most situations is about 2 cm. Finer gravel may be used to fill the annular between the borehole and the well casing. Mixing Concrete: Concrete must be thoroughly mixed to yield the strongest product. Mixing by Hand: The mixing area must be both clean and water tight. Use the following procedure: Spread the sand evenly over the mixing area. Spread cement evenly over the sand and combine until the color is uniform. Spread the mixture out evenly and add the gravel on it and mix it thoroughly again. All dry materials should be thoroughly mixed before water is added.

Shape dry mix into a pile and form a hollow bowl in the center. Pour some of the water into the bowl, gradually mixing in the dry mixture until all the water is adsorbed. Re-form the pile and bowl, add and mix more water. Repeat until concrete is ready to pour. Curing: After the forms are filled the concrete must be cured until it reaches the required strength. Curing involves keeping the concrete damp so that the chemical reaction that causes the concrete to harden will continue for as long as necessary. Once the concrete dries the chemical hardening will cease and cannot be reactivated. The best way to keep the concrete wet in very hot countries is to plug to drainage channel soak-away pit and then fill the concrete pad and drainage channel with water. Water can be added as needed to keep the concrete covered. b. INTERPRETATION The compressive strength of concrete specimens as shown on figure 3 reveals that compressive strength of pure concrete increases with respect to increase in curing period, whereas the compressive strength of composite concrete increases up to 7 days curing period and then, it showed irregular change in compressive strength. The slope of pure concrete is much steep over the slope of composite concrete. 75% replaced composite concrete showed remarkable increase in compressive strength in period of 714 days, whereas it also showed significant decrease in compressive strength in period of 14-21 days. V. DISCUSSIONS Compressive strength is the capacity of a material or structure to withstand axially directed pushing forces. It is a good parameter in order to determine possibility of the use of construction waste. 28 days composite concrete got around 2300 psi of compressive strength which is not satisfactory to ACI 211.1. The standard proportions designed by ACI may not be fit to concrete mix design of composite concrete using construction waste. The other parameters such as flexural, tensile strength, workability, permeability, and etc. should be determined in order to apply composite concrete in construction works. The irregular change in compressive strength is shown on figure.3. Such change is not appropriate to the construction works which require structural or mass concrete. Hence, the use of composite concrete using construction waste should be limited to residential dwellings. Admixture is a material other than water, aggregates or Portland cement, that is used as an ingredient in concrete and is added to the batch immediately before or during its mixing. Supposedly, the irregular change in compressive strength might be reduced or eliminated with the use of admixtures. VI. CONCLUSION AND GENERAL RECOMMENDATIONS This study is a partial fulfillment in course CE 405 collaborated with 4 groups of students. This chapter aims to conclude optimum ratio of replacement of coarse aggregates. Based on the findings of this study, it is concluded that there is a feasibility for the use of construction waste as coarse aggregate in concrete. Compressive strength of concrete containing construction waste may reduce with

increased construction waste replacements for curing period 14-21 days. The recommended construction waste replacement for coarse aggregates is 25% for normal concrete (referred to DoE of 25% replacement data). Higher replacements should be elaborated on with the use of admixtures. For furthermore studies, it is recommended the increase of number of batches and specification of construction waste.

VII. REFERENCES REFERENCE Dabhade, A.N., Dr. Choudhari, S.R., Dr. Gajbhiye A.R., (2012) Performance Evaluation Of Recycled Aggregate Used In Concrete, IJERA 2(4): 1387-1391. Dhir, R.K., Limbachiya, M.C. and Leelawat, T. (1999) Suitability of recycled concrete aggregate for use in BS 5328 designated mixes, Proc. of Civil Engg. Struct. Build, 134: 257-274. Kumutha, R. and Vijai, K., (2010) Strength of concrete incorporating aggregates recycled from demolition, ARPN Journal of Engineering and Applied Sciences, 5 (5): 64-71. Limbachiya, M. C., Leelawat, T., Dhir, R. K., (2000) Use of recycled concrete aggregate in high strength concrete, Materials and Structures, 33: 574 – 580. Domone, P., & Illston, J. (2010). Construction Materials: Their Nature and Behaviour, Fourth Edition . London: CRC Pres ASTM C39 / C39M - 18. (n.d.). Retrieved from https://www.astm.org/Standards/C39 ACI 211.1. (n.d.). Retrieved 211.1&item_s_key=00003286

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