Stone Masonry consists of stones with sizes as shown in Table 57 laid in

Stone masonry consists of stones with sizes as shown

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Stone Masonry consists of stones with sizes as shown in Table 5.7 laid in accordance with the lines and grades as shown in the plans or as directed by the Engineer, jointed by cement mortar of 1 (cement) : 2 (sand) at trowel consistency. Ws Wc Leaning Type Retaining Wall where: Wc = Weight of Concrete Ws = Weight of Soil
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Guidebook for Road Construction and Maintenance Management 5 - 23 The construction steps are shown below. 1. Prepare the foundation bed, compact and moisten as per Specifications. Mortar that is not used within 90 minutes after the water has been added shall be discarded. Re-tempering of mortar is not permitted. Weepholes shall be provided unless otherwise shown on the plans or as directed by the Engineer. 2. Lay 5-10 cm thick mortar 3. Embed Stones of specified size 4. Fill the spaces between stones with new mortar 5. Repeat steps 2-4 until the required dimension is attained. Figure 5.36 Construction steps for Stone Masonry 5.5.2 Grouted Riprap Grouted riprap shall consist of the furnishing and placing of riprap with filter backing, furnished and constructed in accordance with the specification and as to lines and grades and dimensions shown on the plans. This is commonly used in slope protections, abutments, lined canals and other places called for in the plans. (c) (d) (e) Surfacing Figure 5.37 Construction steps for Grouted Riprap
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5 - 24 Guidebook for Road Construction and Maintenance Management Grouted riprap shall be constructed in accordance with the following steps: (a) Prepare the foundation bed, compacted and moistened as per with specifications. (b) Lay 5-10 cm thick 1:3 mortar mixture (cement 1: sand 3). (c) Embed slightly moistened stones of specified sizes into the fresh mortar. (d) Fill the voids in between the stones with mortar. (e) Repeat the above steps a until the specified dimensions are attained. Figure 5.38 Grouted Riprap Table 5.7 Materials Requirement for Grouted Riprap and Stone Masonry Item Grouted riprap (Item 505 Stone masonry (Item 506) Stones Class A: 15 kg to 25 kg Class B: 30 kg to 70 kg Class C: 60 kg to 100 kg Class D: 100 kg to 200 kg Thickness: 150 mm or more Width: 150% of respective thickness or more Length; 150% of respective width or more Mortar Cement (1) : Sand (3) Cement (1): Sand (2) Min. Thickness Class A: 300 mm Class B: 500 mm Class C: 600 mm Class D: 800 mm As per design Weepholes Horizontally at the lowest points, Not more than 2.0 m center to center in a staggered manner. The length should not be less than the thickness of the walls, at least 100 mm dia. PVC is recommended. (Source: DPWH Standard Specifications for Highways, Bridges and Airports, 2013Edition) 5.5.3 Cribwall 5.5.3.1 Stone Masonry and/or Reinforced Concrete Cribwall It is a type of retaining wall particularly made up of concrete or stone masonry (or a combination of both) and supported with reinforced concrete frame. Generally, a double frame type is adopted for a 3.5 to 5.5 m. height of slope.
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  • Fall '18
  • Prof Robles
  • Road, Unified Soil Classification System, Silt

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