CN202936805U

CN202936805U - Foundation for treating deep collapsible loess

Info

Publication number: CN202936805U
Application number: CN 201220596935
Authority: CN
Inventors: 彭亦亮
Original assignee: Hennan Electric Power Survey and Design Institute
Current assignee: Hennan Electric Power Survey and Design Institute
Priority date: 2012-11-14
Filing date: 2012-11-14
Publication date: 2013-05-15
Anticipated expiration: 2022-11-14

Abstract

The utility model provides a foundation for treating deep collapsible loess, wherein two-eight ash-soil cushion layer is paved on the treated region dynamically compacted previously; a blind ditch is formed on the two-eight ash-soil cushion layer; a water collecting pipe is laid in the blind ditch and a round hole is formed on the water collecting pipe; and the water collecting pipe is communicated with a water catchment pipe. The foundation with the technical scheme is characterized in that the collapsible loess of the top layer is excavated and then dynamic compaction is performed in the foundation pit, the two-eight ash-soil cushion layer which is 3 m thick is then formed on the dynamic compaction surface after the completion of dynamic compaction, and finally, the blind ditch is formed on the cushion layer. The dynamically compacted soil is obviously improved in bearing capacity; the two-eight ash-soil cushion layer is capable of functioning as a short-term water isolation layer, and the blind ditch formed on the cushion layer is capable of draining surface water penetrating on the cushion layer in time, so that the water is prevented from penetrating into the soil of the lower part to cause collapse; and therefore, the safety of the structure is guaranteed.

Description

A kind of ground of processing deep layer collapsible loess

Technical field

The utility model relates to a kind of brand-new deep layer collapsible loess foundation and processes means.

Background technology

Collapsible loess is wider in China's distribution, and saturated yielding grade and soil thickness differ, and need adopt pile foundation to penetrate yellow soil horizon of collapsibility or adopt method for processing foundation to process the following whole yellow soil horizon of collapsibility of foundation bed when building the Class A building on the self weight collapse loess place.If adopt the pile foundation expense higher when deep layer collapsible loess carries out the basic engineering of Class A building, adopt strong rammer or change method for processing foundation such as filling out bed course when deep layer collapsible loess processed thicker because of yellow soil horizon of collapsibility, be difficult to all eliminate the settlement by soakings of soil layers.

Summary of the invention

For overcoming above-mentioned deficiency, the utility model proposes a kind of brand-new deep layer collapsible loess processing method, can effectively prevent deep layer collapsible loess generation saturated yielding, and significantly improve soil body supporting capacity, save investment.

For achieving the above object, the utility model is by the following technical solutions:

A kind of ground of processing deep layer collapsible loess, it is included in lays sixteen cushion limes on processing region after strong rammer, lay french drain on sixteen cushion limes, lays header in described french drain, have circular hole on header, and header communicates with collection pipe.

Bottom of trench at french drain arranges sand-gravel cushion, and every limit of sand-gravel cushion all is wider than french drain.

Bottom of trench and sidewall at french drain are laid geotextiles, lay the cobble loaded filter between header and geotextiles, at geotextiles outside laying medium sand loaded filter.

Axially at interval of 40m, a manhole is set along described header.

Header in described french drain adopts pvc pipe, and makes a call to 12 along all equally distributed circular holes of pipe, circular hole aperture 12mm interlacing interlaced arrangement on header along header longitudinal separation 150mm.

Adopt the utility model of technique scheme, first the collapsible loess on upper strata excavated, carry out afterwards strong rammer in foundation ditch, do sixteen thick cushion limes of 3m after strong rammer is completed on the strong rammer face, french drain is set on bed course at last.Soil body supporting capacity after strong rammer significantly improves, and sixteen cushion limes can play the effect of short-term water barrier, and the french drain that is arranged on a bed course can in time be drained the surface water that infiltrates on bed course, and anti-sealing infiltrates and causes saturated yielding to guarantee structural safety in the soil body of bottom.

Fig. 1 is layout plan of the present utility model.

Fig. 2 is french drain profile in the utility model.

The specific embodiment

As shown in Figure 1 and Figure 2, a kind of ground of processing deep layer collapsible loess, strong rammer after excavating on full wafer processing region 9, and sixteen cushion limes after strong rammer face upper berth 3m, along processing region periphery french drain 1, and look for the slope by arrow direction indication in Fig. 1, provide safeguard for natural drainage is unobstructed.At the interior laying header 2 of french drain 1, have circular hole on header 2, and header 2 communicates with collection pipe 4.

The specific practice of french drain 1 is as follows:

(1) header in french drain 12 adopts pvc pipe, and the caliber of header 2 is selected according to amount of precipitation, and makes a call to 12 along all equally distributed circular holes of pipe, circular hole aperture 12mm interlacing interlaced arrangement on pipe along pipe longitudinal separation 150mm.

(2) at 1 end of ditch, the thick sand-gravel cushion of 100mm 8 is set, every hem width of sand-gravel cushion 8 goes out french drain 100mm.

(3) lay geotextiles 6 at bottom of trench and the sidewall of french drain 1, to cut apart cobble loaded filter 5 and medium sand loaded filter 7, geotextiles 6 is not less than 100mm in french drain lap length suitable for reading, and along underflow direction overlap joint.

(4) in the french drain of completing geotextiles 6, be between geotextiles 6 and header 2, cobble loaded filter 5 to be set, the cobble loaded filter is selected the clean cobble of 5～10mm, and the boulder bed of header 2 bottoms part should be looked for the slope by the gradient of header 2 when laying the cobble loaded filter, is strictly on guard against refluence.

(5) side of french drain 1 and end face setting are not less than the thick medium sand loaded filter 7 of 200mm.

Need to prove, above-mentioned cobble loaded filter 5 and medium sand loaded filter 7 can prevent effectively in Precipitation Process that foreign material from entering or stopping up header.

Due to the existence of french drain 1 and the reasonability of structure, make the enough filtrations by loaded filter of the surface water that infiltrates on sixteen cushion limes successfully enter in header 2.Axially at interval of about 40m, a manhole 3 can be set along header 2, with the silt in water in the sedimentation and drawing process, guarantee the unobstructed of header.By the precipitation of manhole 3 and enter in collection pipe 4 along drainage grade, finally pour in drainage pipeline networks, realized the function of draining, anti-sealing enters lower floor's soil body and produces saturated yielding.

Claims

1. ground of processing deep layer collapsible loess, it is characterized in that: it is included in upper sixteen cushion limes of laying of processing region (9) after strong rammer, lay french drain (1) on sixteen cushion limes, lay header (2) in described french drain (1), header has circular hole on (2), and header (2) communicates with collection pipe (4).

2. the ground of the deep layer of processing according to claim 1 collapsible loess, it is characterized in that: the bottom of trench at described french drain (1) arranges sand-gravel cushion (8), and every limit of sand-gravel cushion (8) all is wider than french drain (1).

3. the ground of the deep layer of processing according to claim 1 collapsible loess, it is characterized in that: bottom of trench and sidewall at described french drain (1) are laid geotextiles (6), lay cobble loaded filter (5) between header (2) and geotextiles (6), at geotextiles (6) outside laying medium sand loaded filter (7).

4. the ground of the deep layer of processing according to claim 1 collapsible loess, is characterized in that: axially at interval of 40m, a manhole (3) is set along described header (2).

5. the ground of the deep layer of processing according to claim 1 collapsible loess, it is characterized in that: the header (2) in described french drain (1) adopts pvc pipe, and upward make a call to 12 along all equally distributed circular holes of pipe, circular hole aperture 12mm interlacing interlaced arrangement along header (2) longitudinal separation 150mm at header (2).