MKT VIBRATORY HAMMER SELECTION AND SOILS TRAINING

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1 MKT VIBRATORY HAMMER SELECTION AND SOILS TRAINING While reviewing this guide if you see this symbol please click to the next slide. Press the F5 key when you are ready to start the slide show.

MKT MANUFACTURING, INC. 1198 Pershall Road St.

2 MKT MANUFACTURING, INC Pershall Road St. Louis, MO Toll Free: (800) Website: MKT Manufacturing, Inc. Company Office

3 MKT MANUFACTURING, INC MKT Manufacturing, Inc. was founded in St. Louis, MO in 1986 We are a manufacturer of Pile Driving and Drilling Equipment such as vibratory drivers / extractors, hydraulic augers, air hammers, lead systems, accessories, and custom / design manufacturing.

MKT Side Clamp Vibros have been proven to be of the most durable in the industry. Equipped with both side and lower clamps, as well as the Rototilt on top.

4 MKT Side Clamp Vibros have been proven to be of the most durable in the industry. Equipped with both side and lower clamps, as well as the Rototilt on top. Convertible to a crane hung application (with Power Unit) EXCAVATOR MOUNTED VIBRATORY DRIVER / EXTRACTOR SYSTEMS: Controls 1. Wired pendant controls 2. Wireless remote controls 3. Joystick controls MKT V-2Esc w/ Side Clamp

5 HOW A HYDRAULIC VIBRATORY DRIVER / EXTRACTOR SYSTEM WORKS: A vibratory hammer drives a pile through a combination of driving force, frequency, amplitude, and weight. The driving force of a hammer is determined by it s eccentric moment & steadystate frequency.

6 HOW A VIBRATORY DRIVER / EXTRACTOR SYSTEM WORKS: The eccentrics of a vibratory hammer are attached to a gear, and are mounted in pairs along side one another on a horizontal plane inside the gearbox. The pinion shaft(s) are connected to a hydraulic motor(s) mounted to the outside of the gear box. As the pair(s) of eccentrics rotate (in opposite directions), their horizontal forces cancel one another out, leaving only vertical movement causing the vibration. (see the following diagram)

7 HOW A VIBRATORY DRIVER / EXTRACTOR SYSTEM WORKS: Position # 1 Position # 3 Position # 2 Position # 4

8 HOW A VIBRATORY DRIVER / EXTRACTOR SYSTEM WORKS: By virtue of being firmly clamped to the pile, the vertical vibration created in the gearbox by the rotating eccentrics is transmitted into the pile being driven. The vibrations exerted through the pile and then into the soil cause a process referred to as soil liquefaction. This occurs when the granular particles in the soil become loose & jumbled, or liquefied. The shearing action created by the vibration of the pile coupled with the combined weight of the hammer & pile allows for the pile to be driven through the liquefied soil.

9 DEFINITION OF VIBRATORY TERMS: Eccentric Moment term used to describe the effectiveness of a force to produce rotation about an axis. It is the value in inch-pounds equal to the weight of the eccentric multiplied by the distance from the center-line of gravity to the center-line of rotation, then multiplied by the total number of eccentrics used in the machine. The eccentric weights are mounted to gears inside the exciter case.

10 DEFINITION OF VIBRATORY TERMS The size of the eccentric moment affects the driving force, attainable amplitude, operating frequency, and power requirements for the exciter. Amplitude the vertical movement (distance) of the total vibrating system, and the direct result of the applied force generated by the rotating eccentrics

11 DEFINITION OF VIBRATORY TERMS Vibrating Mass The total weight (below the suspension housing) of the hammer & pile set in the upward and downward motion when in operation Frequency - the number of cycles, or rotations per minute the system can achieve while free-hanging Steady-State Frequency - the number of cycles per minute the system can achieve while attached to a pile and introduced to the dampening characteristics of the soil being penetrated

12 DEFINITION OF VIBRATORY TERMS Driving Force The force, measured in tons, which is generated by the rotating eccentrics (centrifugal force) and the speed (frequency) at which they are turned. Power The horsepower available to deliver the required gallons per minute of hydraulic fluid under a required pressure to the hammer motor(s)

13 SELECTING THE PROPER SIZE MKT VIBRO Gather the required data: Type / size of pile to be driven i.e. HP12 x 53 H Pile, PZ 27 sheet pile, etc. Length of pile to be driven Generally speaking, the V-2Esc is good for piles up to 20 in length, the V-5Esc is good for piles up to 40 in length. Figure the weight of the pile the V-2Esc is good for piles up to 1,000 lbs., the V-5Esc is good for piles up to 4,000 lbs.

14 SELECTING THE PROPER SIZE MKT VIBRO MKT V-2Esc Requires an excavator in the 50,000 lbs. weight class with an arm width up to 16.5 inches and 100 mm pins (max). Requires a one-way auxiliary circuit capable of 45 2,500 psi For driving single piles weighing up to 1,000 lbs. MKT V-5Esc Requires an excavator in the 80,000 lbs. weight class with an arm width up to 16.5 inches and 100 mm pins (max). Requires a one-way auxiliary circuit capable of 90 3,500 psi For driving single piles weighing up to 4,000 lbs.

15 SELECTING THE PROPER SIZE MKT VIBRO 1. Calculate the Amplitude: Amplitude = (eccentric moment) (in inches) (vibrating mass) x 2 Note: V-2Esc eccentric moment = 550 inch-pounds V-2Esc vibrating mass = 3,000 lbs. + pile weight V-5Esc eccentric moment = 1,300 inch-pounds V-5Esc vibrating mass = 6,400 lbs. + pile weight

16 SELECTING THE PROPER SIZE MKT VIBRO Example: An MKT V-5Esc vibratory driver / extractor for driving PZ-27 x 40 feet long sheet pile: What amplitude can the contractor expect prior to penetrating the soil? PZ-27 = 40.5 lbs. / foot x 40 = 1,620 lbs. A = 1,300 inch / lbs. 6, ,620 x 2 A = 1,300 / 8,020 x 2 =.324 inches

17 SELECTING THE PROPER SIZE MKT VIBRO As a rule of thumb for effective driving, the hammer must have an amplitude equal to or greater than.250 (1/4) inch. Generally speaking, the higher the amplitude, the more effective the hammer will be at driving pile in soils considered marginal Higher amplitudes may also increase risk of damage to adjacent structures. Be sure to have trained professionals carefully evaluate soils & project information

18 HAMMER SELECTION & SOILS ANALYSIS Soil Boring Data: In order to accurately select a hammer for a given project, a basic understanding of both the hammer and soil system are necessary. However, this is not an exact science, and several factors should be taken into consideration. Successful piledriving with a vibratory hammer is contingent on good knowledge of the site & soil conditions.

19 HAMMER SELECTION & SOILS ANALYSIS Analyze available soils information read any and all available soils reports on the project. Important areas of concern on these reports include the blow count (also referred to as N value, or SPT ), moisture content, type of soils, profile of pile to be driven, pile layout, etc.

20 HAMMER SELECTION & SOILS ANALYSIS STP: Standard Penetration Test An open-ended hollow tube, referred to as a split-spoon sampler, is used to collect 18 of material (per sample), using a 140 lb. hammer that is dropped from 30 inches high. The 18 samples are typically taken every 5 feet down. The first 6 of each soil sample are considered disturbed during this type of testing, and therefore disregarded. The final 12 are collected and analyzed.

21 HAMMER SELECTION & SOILS ANALYSIS The N value, or blow count, equals the sum of the number of blows required to penetrate the last 12 inches of each soil sample taken. The V-2Esc works best in soils up to a 10 blow count material. The V-5Esc in soils up to a 20 N value, or blow count material. Using the hammer s amplitude that you calculated earlier, compare this to your soil analysis down to the depth at which the piles are to be driven

22 SOILS ANALYSIS Please see memory stick for soils reports.

23 SHEET PILE-DRIVING Every precaution should be taken to select the proper type of pile, and to install them safely and effectively. When driving a sheet wall, take time to ensure the first pile is driven accurately, vertically, and / or plumb. It is then much easier for subsequent piles to be interlocked with the first pile, which acts as a guide for the remainder of the wall. Always lead with the male interlock In general, sheets should be driven or extracted at a rate of 1 foot per minute or more, in order to prevent overdriving and potential damage to both the sheet pile and the hammer.

24 THIS CONCLUDES THE HAMMER SELECTION AND SOIL ANALYSIS TRAINING PRESENTATION If you have any questions please click on for your nearest MKT representative

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